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Vorshlag C5 & C6 Corvette Development + NewBalance and Rampage

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  • Vorshlag C5 & C6 Corvette Development + NewBalance and Rampage

    NEW C5/C6 DEVELOPMENT SUPER THREAD

    This thread is now merged from three different C5 & C6 Corvette development threads. There was so much cross-over among these 3 threads that it became easier to merge them and update them all here. Sorry for any confusion!



    Project Introduction - March 26th, 2021:
    We just bought a 2006 Corvette for Amy to use to at autocross, on track, and on the street. This will be a rules-free build that will be done on a "normal" budget, with an emphasis on both streetability and great on-track manners. While this car might see some use in autocross or time trial, it will NOT be built strictly for those purposes or around any given rule set. Just a "fun buggy" that serves as a back-up car for when our main race cars are down that can actually be driven to events.



    And here it is in all of its 16 year old, used car glory! This is a "narrow body" base model C6, with a 6-speed manual and 45K miles that we bought for $20K. It is bone stock and overall in 98% perfect shape mechanically and about 95% perfect visually. A squeak under hood, a few scratches, and the wheels have some road rash - all things that are easy to fix/replace with parts we had planned.



    Now many of you reading this are likely wondering - why wouldn't we buy a widebody Z06 or Grans Sport if you wanted to get a C6 Corvette for performance use?!? It came down to two things: First was cost. I looked at comparable mileage C6 Grand Sports were more than double ($43K+) and low mileage C6 Z06 cars were higher still ($50K+). I found only higher mileage (usually 120K+) narrow body C6 cars for the same or more costs, and 100% of those were automatics (yuck). It was an easy purchase that we could get on track immediately.



    Second was: low stress. This C6 being a less desirable "narrow body" means we won't be as inclined to "go crazy" and build some wild race car (plus I already have an all carbon widebody C6 Z06 in storage, waiting for a complete build, above). As a relatively low value C6 we won't stress out if it gets a scratch or a tiny bit of cosmetic damage. I try to explain further why we went this route below...

    HISTORY, MODEST GOALS & BUDGET

    Vorshlag started out 16 years ago developing parts for the most flawed cars, and our unofficial motto was "We make your car SUCK LESS." The more terrible the OEM suspension, the more improvement we could offer! Most sporty car models then (as now) were built with McPherson strut suspensions, soft spring rates, inadequate roll stiffness, skinny wheels and tires, and all sorts of other performance compromises.

    This is where we started.... strut suspension cars




    We started out with BMWs and Subarus as the primary targets of our parts development, and that method of attacking the "low hanging fruit" has paid off for the business. I am glad we went that direction, instead of chasing true sports cars that came with MUCH better stock suspension options. And in extreme cases we even swapped in LS engines, which I first stared doing in 2002.

    Cars with terrible suspension are easy to make big improvements on!




    But the year before we started Vorshlag (2004), Amy walked into a GM dealership to look at the then brand new C6 Corvette. This was just days after the new generation Corvette hit the streets, and it was a radical departure from the C5 generation before it (which neither of us liked, since the C5 is the Corvette with Four Asses). She saw a new C6, fell in love, and custom ordered a 2005 Corvette Z51 6-speed in silver. It arrived a few weeks later. It came from the factory with decently wide wheels, world class suspension, and LS2 power - with a 186 mph top speed in stock form.

    This was our 2005 C6 Corvette Z51 - which we ordered new in 2004




    This was her first new car purchase and it was just an amazing car, which she loved. We both autocrossed it a few times (after several years away from that sport) but mostly she drove it to work and loved every minute of it. I hooned it a bit... took it to Houston Raceway Park and ran the 1/4 mile (12.8@112), weighed it on a scale, dyno'd it (355 whp). The wheel offsets needed proved to be a challenge so I bought some 17x11" C4 ZR1 rears and we ran 315/35/17 Hoosiers, which poked like crazy!

    We sold our 2005 Z51 to help pay for a new home + shop, to concentrate on starting Vorshlag in 2005




    But in 2005 when we had just started Vorshlag and had some tough choices to make. Keep a relatively expensive new car / note ($45K) while building an expensive new home with giant attached shop (which we ran Vorshlag out of from 2006-11)? A car we would have trouble applying our Vorshlag fixes to? It did not help the business, and it was a tough choice, but we sold it after 1 year - to a dealer, who paid us sticker price - because NOBODY could get C6 models at the time, and our rare Z51 6-speed no option car was SUPER rare at the time (90% of early C6 models are automatics).

    My main track car (S550 Mustang) was sold. Amy's FR-S is being LS swapped and stuck behind customer cars




    Fast forward 15 years, and after many years of having multiple track and autocross capable cars at any given time, 2020 was a bleak year for racing in the Fair household. We sold my 2018 Mustang (above left) in August 2019 to move onto a more serious S550 race car build, but that stalled out with manpower limitations in our shop and a customer car build backlog. Likewise Amy's 2013 FR-S (above right) was pulled from racing duty in late 2018, but the LS swap work on that car stalled out for the same reasons. So Amy and I haven't raced anywhere in our own cars going on two years! Neither of us like borrowing cars either. We're both going stir crazy NOT competing track or autocross events.

    I have been bumming co-drives for a year in a friend's C5 we used for development




    At an event at Eagles Canyon Raceway a week ago (above), Amy was lamenting our "stalled out" race car builds and declared - "It is time to buy another car, that runs, that I can race RIGHT MEOW." We puzzled over a few ideas while in the drivers lounge with some friends, and Jason here at Vorshlag mentioned this 2006 Corvette he had for sale... Yadda, yadda, yadda.... she bought it!

    Of course, every car we buy for the business has to "earn its keep" here at Vorshlag. 16 years after starting Vorshlag and we are indeed developing parts for more than just "Crappy McStrut" suspension cars. We have even had some success with our products developed for the C5 platform, among other non-strut cars.



    For this narrow body C6 have a small budget for this one, and overall build will be fairly mild - we want to keep this a 100% street legal, nice driving car *that is also track capable* and quick. Goals do NOT include TT track records or some SCCA obscure autocross class rules - just an all around "fun buggy" that she can run "where it fits".



    While Vorshlag is not known as a "Corvette Shop", we still make a number of unique parts for some Corvette models and have worked on a number of C4, C5, C6, and C7 Corvettes over the years (and I have personally owned 5 Corvettes - two C4s and three C6s). For this narrow body C6 there are a number of areas we can improve with our part solutions - which we will prove with track testing, data, and product development.



    Initial plans for this car include the usual Vorshlag upgrades: custom wheels and wide 200TW tires, MCS non-remote coilovers, G-LOC pads on fresh Z51 rotors, adjustable swaybars, maybe seats, and of course a number of new C6 specific "track products" from Vorshlag. We will share the development of the car and these parts in this forum build thread, of course.

    I have driven numerous C4, C5, C6 and C7 Corvettes at Motorsport Ranch on their 1.7 mile CCW course




    Will get a baseline lap in stock form at two race tracks: MSR Cresson and/or ECR. Having driven 500+ laps at MSR in dozens of cars and 1000 laps at ECR (on the old 2.9 mile layout), with dozens of wins and class track records in Time Trial at both locals, these tracks will be best suited for our initial and continued testing on this C6.



    Baseline laps will be done with just with fresh Motul RBF600 brake fluid and stainless brake lines (which the C6 already has). We will go back after each major round of parts changes to chronicle any lap time gains or losses. To help with this testing we purchased a membership at Motorsport Ranch and a membership at Eagles Canyon is coming shortly.

    FIRST INSPECTION & WEIGHING

    On March 25th, 2021 we put the new C6 on the lift for the first time to take a look at the car more closely. Brad wiggled all of the bushings, wheel bearings, noted any leaks or issues. First things we noticed that needed replacement: idler tensioner pulley, engine mounts, oil pan has a slight leak, hood lift struts were shot, and I wanted to do a full oil & filter replacement. We will also swap in fresh plugs (NGK TR6), plug wires (Taylor 10mm), and plug wire heat boots (DEI).

    We also, of course, got an initial weight. And it was a pleasant surprise, and a relief after dealing with 3600 pound pony cars for the last fee years.



    Ideally I like to weigh a car with the fuel tank as empty as possible. This makes it is easier to compare car-to-car weights. Why empty and not full? Because we almost NEVER autocross or track a car on a full tank, but have done those events with low fuel levels (There is no such thing as "good ballast weight"). We run the least amount of fuel needed for the session and/or to prevent fuel starvation. But this one had 5/8ths of a tank when we bought it, and we didn't have a lift clear for very long so we took the weight we could get.

    Now my memory of our 2005 Z51's weight was 3148 lbs, which I weighed at a drag strip in 2005 - but that was 16+ years ago, before we really started Vorshlag, before we owned our own digital scales, and before I began documenting EVERY weight on EVERY car we owned or worked on. Plus, that 2005 Z51 had bigger brakes and wheels than this 2006 "base" car, so maybe that makes up for some of the weight difference? Or maybe my memory isn't 100%...

    continued below
    Last edited by Fair!; 11-10-2023, 05:06 PM.

  • Fair!
    replied
    continued from above

    EXHAUST BYPASS SOLENOID + SEAT HEATER SWITCH

    We added several switches to the old "ash tray" section of the center console (like, do people still smoke inside cars now?) including the two mode seat heater switch and this dual USB / volt meter. The ABS trouble light for the Mk60 also went into this now fixed panel. But something new was added in January of 2023...



    This was when we put the "stealth mode" switch for the C6 Z06 muffler bypass. We had been running these 3" mufflers with the new LGM exhaust for a while



    This was done a while ago and since then the plumbing and wiring was re-done, but this shows the video of the muffler open and closed...



    Pretty amazing difference and more and more cars are coming with these "internal bypass" valves, like our 2024 Mustang Darkhorse. On this C6 it makes a huge difference in sound levels at idle, cruise and wide open throttle.

    PREPPING C6 FOR SALE / INTRO

    The C6 is just too perfect to just let sit and gather dust. When I was over-ruled on keeping the Corvette, we had the car painted and detailed in February, March was when we did the heads/cam/intake/tune, and then April and May was spent doing some final repairs and detailing the car.



    It didn't take much, as we always kept this car super clean and stored indoors. But once the final detail and vacuuming was complete, it was time for good "for sale" pictures.



    Brad took dozens of pictures of the car inside / out / underhood, then the C6 sat under the car cover waiting for me to finalize the car for sale page...



    You can see all of this here: https://vorshlag-store.com/pages/for...jectnewbalance

    WHAT'S NEXT?

    The ad page I made worked very well and it only lasted a few days. The C6 might already be sold, but I will confirm shortly when the funds arrive.



    We have a number of sets of wheels that were leftover from this narrow body C6 project - I will post those up shortly and/or repurpose them for another few GM projects we have in the works. We will know more soon.



    We also have decided to revived our all carbon C6 Z06 chassis, Project #Rampage (see build thread here), and we will continue to use this thread to chronicle that as it starts to move back into the shop schedule. I also merged the original ProjectNewBalance + C5 Development + C6 Rampage threads with this one - let's hope I didn't screw that up.



    Thanks for following along on the Narrow Body C6 - it was a fun build, we learned a lot, and got some cool parts out of it. Going to make somebody a very nice race / street car. We will keep adding to this thread on the C5 work we've done as well as the Rampage project we're about to kick off again.

    More soon!

    Leave a comment:


  • Fair!
    replied
    continued from above



    The "lightly used" front rotors that came with this used C6 Z06 brake kit were now trashed, but we sourced some "solid faced" replacements from Centric (no cross-drilled or slotted nonsense).



    And like the factory brake rotors, the aftermarket replacements are all made only for the one corner of the front axle - with backwards vanes on one front location. That's been how its been for a long time, and they still work. Blame GM, don't hate on me!



    Had high hopes that this cooling solution would finally give us solid, reliable brakes for this C6 (it did!). Two years I have been babying the brake pedal, never knowing if it will lock, fade, or stop.

    NEW REAR MCS RESERVOIR MOUNTS

    It was getting close to time to start prepping this C6 for sale and one of the open tasks I had was making "prettier" mounting brackets for the Motion Control Suspension remote canisters.



    I was never happy with the rear mounts, which were down inside the two storage cubbies and just zip tied to some factory plastics. Started with some templates...



    Ended up with these curved mounts that bolt to the rear fenders, where the targa top brackets normally sit. Clean install out back now. The front was cleaned up months earlier.

    C6 TRACK TEST #12 - DEC 29, 2022



    This was a busy day but beautiful weather for testing (55-69F), after some precip burned off. We went out to MSR Cresson with the C6 for the car's 12th dedicated test and our 2023 BRZ's 4th track test. I drove both the 2006 Corvette on the 295mm Hoosier R7s and the 2023 BRZ on 225 Falken RT-660s, and Amy also took laps in the BRZ.



    The BRZ was using MCS dampers on the 225mm Falkens, and the MCS shock change picked up 3 sec over the last test. Big improvement! On the C6 and we tested brake cooling with an 8 lap then 11 hot lap stint - best they have ever been! I also drove Scottish Joe's C8 Corvette, which was eye opening.



    Up until this point we never could manage more than 2-3 hot laps in the C6 before the brakes overheated - with 3 different brake systems (base, Z51, Z06) and all manner of track worthy brake pad compounds. Well this time with our C6 brake cooling deflector the brakes were OUTSTANDING! I did an 8 lap stint, then an 11 lap stint, and the brakes never let me down, never lost bite. We also saw the highest braking g readings (1.19g) that we have seen in 2 years of trying. WOO!!!



    There was a lot of traffic, and with the R7s the lap times were kinda "meh", but I could run a string of 1:20 laps with ease, as the brakes never went off like before. Big success, right at the end of this project. Wish we had the time to do the Z06 brakes + cooling a bit earlier. Oh well, the next owner is going to benefit from all of this hard work and testing.

    DE-STICKERING THE CORVETTE - PREP FOR PAINT

    Takes a few hours and some heat to get these old decals off. Best bet is to park the car outside in the sunlight on a warm day - it was not a warm day here, so we did this in the shop.



    Man that was painful to watch - all of those decals were part of the last 2 years' history with this car, and I had a feeling this car might never get another class letter / number / series decal while we owned it. But it was necessary to get the car "naked" and ready for the painter...

    CORVETTE GETS PAINTED (60% OF THE PANELS)

    I trailered the C6 over to our friends at Heritage Collision, who have repaired and painted 20+ cars for us and our clients over the last 15 years.



    The owner there, Shiloh, knows that I'm pretty picky for these "shop builds" that need to be sold - I want them to leave our shop in better condition than when we purchased them. This C6 had some "legacy" scratches in the front and rear bumper covers and front fenders, the two rear fenders that got bonked when goofball put the wrong spacers on, and there was some tire klag hits on the roof panel where it needed to be fixed, too. He marked all of the issues in tape and they got to work.



    All of the front and rear lights came out then the two bumper covers came off, as these both needed to be spiffed up and resprayed. The rear fenders came off too (luckily that is easy) for repairs then a full respray, and the roof needed paint - but it is easy to remove.



    I didn't rush them but at the end of February they had the C6 all painted, reassembled, paint corrected and detailed. It looked better than new!



    Carefully brought this back in the trailer and we got to work on the power upgrades that had been planned long ago...

    CNC PORTED HEADS, CAM, INTAKE MANIFOLD, 103MM TB LGM COLD AIR, LGM HEADERS

    Now don't ask me why I decided to do this, but I had delusions of keeping this C6 for a "backup car", as our LS swapped Mustang was being a real pill in the Spring of 2023.



    And with my ties to HorsePower Research, they hooked us up on these CNC ported LS2 years, spec'd out a tiny hydraulic cam, and then I had this cathedral port FAST LSXR 102 intake and 103mm Nick Williams TB, injectors and fuel rails from my Mustang...



    See we had a bit of an issue with the cathedral port 383" LS6 we built for my Mustang, and we decided to upgrade that car to a 454" LS7, so I had all of these brand new parts for a cathedral port LS engine. So the C6 got an 80+ whp bump in power.



    These are single pass CNC ported LS2 cylinder heads, built by HorsePower Research with some really good valve springs, new guides, and all of that. These were installed with ARP head bolts, shown above. The Comp Cams hydraulic roller was spec'd by HPR and it is barely audible when its running, but adds more lift on a wide lobe separation.



    The LS2 intake, stock injectors, fuel rails, "injector covers" and 90mm throttle body came off (and sold for good money) and on went this FAST LSXR 102 intake + 103mm Nick Williams DBW throttle body, and FAST fuel rails (more on that in a second). The entire intake manifold assembly came off my Mustang's 383" engine, and was identical to one we put on a customer's CTS-V race car with a similar 383" LS6.



    I never liked the SLP cold air kit, so we upgraded to this LG Motorsports carbon cold air kit when we changed the intake and such. Really beautiful piece that fit better. We had to tweak the mounting ears a bit as these are made for the later LS3 C6 cars.



    While at LGMotorsports we picked up a nicer set of 304 stainless long tube headers. These have 1-7/8" primaries and 3" collectors, and we opted for their X-pipe with optional catalysts and track pipes.



    We kept it simple for plug wires, with a set of 10.4mm Taylor wires and DEI heat sleeves that worked well with the new headers.



    Fuel Injector Clinic 50 lb/hour injectors (ISC302-0525H) also came from my Mustang's engine, again with minimal run time. We started with some FAST fuel rails but had an issue with the brackets (NEVER USE FAST FUEL RAILS) and upgraded to these billet Deatchwerks rails, which have integrated brackets and are very beefy!



    It all came together and we had it tuned, which I will talk about next. No leaks, issues, or problems - just lots of glorious noises.

    SCCA TT MSR 1.7 CW - APRIL 1, 2023

    We had the car tuned in March and it made good power, and I got permission from Amy (it is technically "her car") to drive the C6 (just painted) in one last Time Trial event, the first Texas Region SCCA TT event of the year. On April 1st.



    Well I sure felt like a fool when we unloaded the car, got the decals on, got all of the timing gear installed, and drove to grid... only to realize we lost throttle control. I missed the first TT session as I putted around Motorsport Ranch looking for a diagnostic tool. Larson Motorsports had a SnapOn scan tool and we could see the throttle pedal commanding the opening percentage, but the throttle body wouldn't open. I could drive around in the paddock but with no throttle opening past idle, eventually I just stuffed the car back into the trailer, utterly disgusted.



    I was moping around, driving Amy's BRZ in Max1 class slowly (which was the class that my Mustang was built for, which I would finally debut later in the year), but my main Max1 competitor for 2023 Stan Whitney saw me in the trailer before the 4th and final TT session. It was a hot day and he told me I could drive the last session of the day in his GT500.



    This is a 760 hp new GT500, with a custom DSC magneride tune, 7 speed DCT sequential, some lowering springs and lots of camber. I hopped in, took 3 laps, and won Max1 class and almost set FTD. Dang that 4200 pound Mustang was FAST and gave me hope that we might be this quick in our own S550 race car later in the year (we were). But the lack of throttle function in the C6 was beyond frustrating. It could have been as fast or faster with the added power!

    TUNING THE NEW LS2

    We went through two tuners getting this C6 right with the new power mods, and I paid for both tunes. The first tune made good power but the throttle body mysteriously quit working on at that SCCA Time Trial event, which was my last opportunity to drive the car on track.



    The tuner wanted to blame parts, so we "fired the parts cannon" and tried a different pedal and throttle body, plus checked all wiring. The problem still persisted. So I called a "gunslinger" tuner that can make house calls, who came by the shop in early May. The "fun" I've had with tuners in 2023, man I could write a book!



    He did a "street tune" - where I drive and he makes changes on a laptop in the right seat. We did about 30 pulls and had it 95% right when the FAST fuel rail decided to YEET itself free from the engine. We both smelled the fuel leak, pulled over, and we made a hasty repair roadside. That's when we went with the DW fuel rails - I won't make that mistake again. Later in September I rented dyno time at LGM and got these pulls.



    Made within 1 hp of what it made in April, but this time with a working throttle body. Oh well, something new we know to look for. Sure wish I could have gotten that Time Trial at this power level, I'm sure it would have been glorious.

    OPTIMA BATTERY UPGRADE (LASTED 4 MONTHS!) THEN REPLACEMENT

    During the engine work phase in early 2023 the old wet cell battery finally went kaput. My problem tech had wired in a solenoid to be powered on all the time and that battery draw killed it. So we replaced it with this new Optima Red Top. It lasted 4 months.



    I only bring this up to point out a pattern of failures we have had since the Pandemic - this is one of NINE Optima or Odyssey AGM batteries we had that failed prematurely in 6 different cars.



    Brad re-wired the entire exhaust solenoid system, and re-plumbed it for cleaner vacuum hard line runs. We swapped the problematic Optimas with O'Reilys 72 month wet cell "Super Start Extreme" batteries on many of the problem cars, and all of the problems .... went away.

    CARBON LIP GOES BACK ON

    After the C6 came back from paint we had a lot of little tasks to make it more sell-able. But the nose was too boring, frumpy. And I really regretted taking off the carbon creations front splitter lip. But back when we put that on we had two reasons to pull it off: 1) it wasn't 100% legal for Tuner class. 2) This thing effectively blocked the factory brake cooling inlets. But now that we had a heads / cam package on this car it wasn't going to be Tuner class legal, so...



    I tasked Brad with cutting holes for our little aluminum brake inlet scoops, which REALLY worked well at track test #12. So he marked the factory inlets in the lower cover onto some paper templates...



    This paper template was transferred to the carbon lower lip, and he sawed out the openings with a jig saw and cleaned up the edges. No going back now, we had to make it work or this splitter was junk.



    The old aluminum scoops were reinstalled and the lip was installed with about 30 rivets, like before. This time was easier as the holes were already in the lower bumper cover. And damned if it didn't look better with that change!



    This splitter lip doesn't impact the flow from the brake cooling inlets with the holes cut and scoops added, so it should be a net benefit with a tiny bit more front downforce. and it looks cool.

    continued below

    Leave a comment:


  • Fair!
    replied
    Project Update for November 10th, 2023: Another bit of time since the last post in the C6 / Project New Balance thread, and a lot has gone down. Our narrow body C6 is already prepped for sale and has seen its last track laps under our ownership. But this build thread still has races to cover, parts to explain, and prep work to go over. And as you might see, I've merged 3 threads into one: everything for all of our C5 & C6 development



    This time we will cover the last few competition events in the C6, as well as a big round of power upgrades I insisted on - then never got to track test! It makes 441 whp now, +80 whp over what it made stock, yet still runs super quiet and smooth.



    The last few months have been a whirlwind - we bought two new vehicles (2023 Bronco and 2024 Mustang Darkhorse - below left), my main race car (2015 Mustang with 454" LS V8 - below right) finally had a breakthrough and is winning races left and right, and Vorshlag has cranked out some cool aero jobs for customers. We've also revived another C6 build - which I will talk about later on in this same thread. We aren't done with C6 development - not by a long shot!

    ​​

    Let's cover the final upgrades, races, and updates to this narrow body C6 before we turn this thread into a build for our widebody all carbon C6, #ProjectRampage. Let's pick up where we left off - October 2022!

    SPACER MISTAKE = REAR FENDERS CRACKED

    One of the guys that worked for me made a big mistake when prepping the car for the NASA event in October 2022 - he put the wrong spacer package on these 19x10" wheels and 295mm Hoosiers. These are the same 19x10" wheels as we have the 275mm Hankooks on (our original control tire) but when running the 295mm Hoosiers they needed a spacer in the rear. He stacked two sets of spacers out back, and it allowed for some poke... and that allowed the tires to contact the rear fenders.



    I figured this out after the first session at MSR during a race weekend, and did some changes in the paddock to prevent further damage - but by then the rear fenders were cracked. It would be different if this wasn't the 4th time the same tech did this sort of thing that cost me paint and body work repairs (he no longer works here). Anyway, those rear fender cracks along with some prior paint imperfections that came with this car are what prompted me to spend several thousand dollars on a partial respray, which I will show later in this post.

    MOROSO C6 COOLANT RESERVOIR

    Another thing that kept happening with the giant 18x11" / 315mm front tire and wheel package was wearing the tire into the plastic coolant reservoir under the hood. The front tire that came with this car was a 245mm, so a 315mm just needs some real room.



    This is a common issue on all C6 cars running a wider tire up front - the left front tire often rubs through the fiberglass inner fender at full lock, then it can touch, wear through and puncture the plastic coolant reservoir, shown above right. We had that happen once and replaced the reservoir already, but it quickly got nicked again by the fat 315mm A052 up front.

    That's when made an aluminum "tire shield" (above left) to cover that small wear hole, but the tire ripped that off a few events later. The prevailing wisdom is to move the reservoir and just "let the tire eat". We spaced the reservoir up 1/2" with some aluminum spacers we make, but it still made me nervous with the nicked plastics.



    Instead of buying a 3rd plastic reservoir, we found this Moroso fabricated aluminum reservoir - and I bought that for my peace of mind. We also spaced that up with the same aluminum spacers to gain more room to the tire. The shape of the tank also includes extra clearance where a fat tire likes to eat, shown above right. A quality piece that should be on any C6 track build with fatter front tires like this.

    NEW C6 Z06 MASTER CYLINDER

    After the last October Time Trial we kept fighting a crappy feeling brake pedal with the new Z06 brakes, even after several fluid bleeding sessions. So we tried a better brand of new master cylinder, again specified for the J56 / Z06 brakes.



    This AC Delco Professional brand master ended up being a new and not rebuilt part, and that bled perfectly as soon as it was installed...



    That made for a better brake system feel on track at the November ECR event, shown below, and is what we will stick with. Name brand parts are always better than rando import brands!

    SCCA TT @ ECR 2.7 CCW, NOV 19, 2022

    This event was COLD (27F-47F) and had a hectic start. We arrived with our narrow body LS2 powered 2006 Corvette C6 only 5 minutes before the 8:15 am driver's meeting, and had all manner of problems to fix before going out in the first track session at 8:45 am - in 34F temps!

    Amy fixed a flat tire on the car in paddock while adding the right wheel spacers, torqued all of the wheels, set tire pressures and brought the car to grid while I ran up the hill and attended the mandatory driver's meeting. I missed the first 2 laps in session 1 - but got a traffic free stint and set 2nd fastest time up to that point (as usual, many folks are really slow to get going).



    This was my first ever time to drive at the new 2.7 mile CCW course at ECR - the last time we ran here going this direction in 2018, it had a different 2.5 mile layout. With virtually every corner changed I spent 4+ hours on the simulator with the #HashtagRacecar map of the ECR 2.7 course the week before, and then learned the course during the rest on this Time Trial.



    I was shocked to be running 2:03 times in the 2nd session (that's relatively quick), and many others couldn't believe that a little T2 car was that far up the grid. Session 2 and 3 produced nearly identical times (see above left), but early traffic in both sessions held back the car's potential (only .055 sec quicker in session 3). Traffic was horrible - I even tried starting from the back of the TT Red grid in session 4, but was still held up and had a poor showing there. That means my session 3 video below shows my best attempt with a 2:03.7 lap. A 2:02 was in the car...



    The video above is from the 3rd session, where I tried 3 different times to find a good gap to put a lap in, but "faster" traffic gridded ahead of me kept holding me up. Some folks don't get quick until their 4th-6th lap, but my driving style (and basic TT strategy) plus these A052s like to get it on lap 1.



    All season I fought this battle of gridding behind folks "slow to get going" and it definitely held back the car's potential this day. Plenty of my normal driving mistakes kept the car from touching a 2:02 lap, but this 2:03.7 time in our little LS2 powered car ended up 5th fastest out of 39 TT entries. We won the T2 class here and that secured the regional T2 championship (whew!) for 2022.



    This was the event where we started to meet more of the SCCA TT regulars, and the 5th overall finish helped folks realize who we were and THAT helped us in the 2023 SCCA TT season get a little more recognition and room on track, even if it was in a different car. We also got to drive the "EQUALIZER" charity car, this 2020 Toyota 86 shown above. We donated Vorshlag camber plates to this car and I dove it again in December (it was over 3 seconds faster with camber).



    This again was my first time running the ECR 2.7 CCW course and I really liked it - I would later come back and run here many times in 2022-23, and its one of my favorite layouts now. I'm running there in a month in Trigger and hope to beat a 1:55 time in the Mustang. This was a weird day and I noticed a tire was flat on the F350 while fueling up at Buc'cees on the way home, and we fixed that before it let go. Amy was the star of the day - just coming to support me, and literally saved my day. Her 2023 BRZ showed up a week later and we brought it back to ECR for some more events.


    That win at SCCA event #7 took us over the top and secured the 2022 Texas Region SCCA T2 championship. I missed the first two events of the year (car wasn't ready!), then won 4 of the next 5 events. My loss at the SCCA MSR 3.1 was the worst showing all year - I'm still learning this track. At least in 2023 I did win Max1 and set FTD at this 3.1 SCCA TT event. Lots of real world practice + simulator time + a faster car helped me finally get it.



    On February 4th, 2023 we went to the Annual Awards Banquet for the Texas region SCCA. We got to see friends and fellow competitors, eat, drink, and receive our award for winning the Tuner 2 championship. How much did we spend to win those 4 races? More than $20,000, but it's best not to add these things up. We had a lot of fun, I got a lot of much needed seat time (after a few years out of TT), and proved that a narrow body C6 could hang with and beat the turbo M2/M3 BMWs, C6 Grand Sports, Shelby GT350s, and Camaro 1LEs. If we didn't get the Mustang running - this C6 was going to do it again in 2023!

    NASA TT @ ECR 2.7 CCW - DEC 3-4, 2022

    This was the final NASA race weekend of the year and Amy and I drove 3 different cars across the two days of Time Trial events. I ran the C6 in TT2 class Saturday, fighting traffic, a long brake pedal and worn out front pads - on the 295mm Hoosier R7s. Why didn't I run the 315mm A052 tires?



    That is a good question, as the Hoosiers were a solid TWO SECONDS SLOWER than the A052 street tires. There were a lot of factors at play to explain this, namely the colder temperatures, crowded sessions / very bad traffic, and my inability to get any heat into these tires to switch them on. If we had enough brake pads for day two I was going to swap on the Yokohamas and shoot for 2:02 times.

    Alas, this was the 3rd and final event on these G-LOC front pads, which died an early death on these Z06 brakes. I explain why below - wasn't the pads fault, just my driving style and CRAP factory brake cooling. Somehow even being 2 seconds slower than the month before on street tires, I managed 2nd out of 7 in TT2 class and set the 4th fastest time of the weekend.



    There was also some nonsense that caused me to miss my first TT session, which hurt my grid placement in the subsequent sessions. I was on grid on time but still putting my belts and gloves on, so I waved the grid marshal to let a few cars behind me go ahead. I was ready when they got to the end, and I communicated a "thumbs up" that I was ready to go.

    But the grid marshal held me and said that I "wasn't ready" and "would slow up the field" if he sent me out. I jumped out of the car and pointed - the cars are still leaving pit lane and its a 2.7 mile course with only 35 cars! Nope, he booted me off the grid. Boy I was super pissed, and had to go out in an HPDE session to get some seat time. Complete bone head call and I took it up with the NASA TT folks later, but it wrecked my whole day.



    This is because I had to start at the back of the grid for the 2nd TT session, and like in the entire season with SCCA TT, I got stuck in massive traffic immediately. Massive amounts of traffic...



    This video shows 4 laps from the 2nd session, where I started dead last. It is super frustrating to watch as all manner of cars hold me up until lap 3, where I finally had one guy who let me by. But there was a "moment" with the rear tires that almost caused me to loop it - and that was my best time. UGH. Lap 4, more traffic, and by lap 5 I had no brakes.

    In the next session I was finally gridded P4 but STILL fought traffic ahead of me and the brakes only got worse. This car just did not get checked out properly at the shop before this event - it should have been on new pads and fresh fluid, and it would have been a much better weekend.



    I also drove the Equalizer 2020 GT86 in 3 timed laps, 2 of which were blocked by other racers. On Sunday, with the brakes totally fried on the C6, we brought Amy's 2023 BRZ, got it log booked, and I ran it in TT5 class in stock form - fighting traffic and killing the OEM front brake pads in the process. Amy drove this car in 2 sessions of HPDE4 to get some seat time.

    A frustrating end to the TT season, where I had expected to run a 2:02 or better lap in the C6, but worn brakes, the grid marshal block, and just slow "early lap" traffic blew all of those opportunities. Bah!

    PREMATURE PAD WEAR + BRAKE COOLING UPGRADES

    After only three Time Trial events with the big 6 piston front / 4 piston rear C6 Z06 brakes, the pads and rotors were trashed. I couldn't even manage a 2nd day at ECR TT above, since the pads were just DONE. I wondered what the heck was going on, because the braking forces just weren't all that great - so we dug into the data and looked closely at the pad wear.



    The outboard pads wore more than the inboard side, so it had to do with brake cooling. We triple checked the calipers and they weren't frozen or bound up in any way. It was time to really tackle the brake cooling deflector design, which we had put off for too long.



    We started by looking at the factory C6 Zr1 brake cooling deflectors, which are plastic and bolt to the (unique) front lower control arms with two threaded holes. And while we could have drilled/tapped the arms on our C6, we wanted to make something we could sell that would be easier for our customers to install. Yes, that is the whole point of this build - make parts people can buy, which are actual solutions to problems. Brake backing plates and hoses are so 1960, and these deflectors DO WORK on the many other cars we've built and tested them with.



    We got pretty far on the ZR1 style deflectors, but I simply refused to make people drill holes in their control arms. So we modified the lower flap to be bigger and further from the front swaybar. We also kept the mounting simple and it attaches to the front swaybar endlink, as shown.



    We also added a "tang" that locates the unit relative to the control arm. It comes down to one nut that holds it on, but the tang keeps it from rotating.



    We also updated the tie rod end / ball joint heat shields, which are made out of stainless steel. We never released these "tie rod boot shields" as a product, but might if the need arises. Sure keeps the ball joint boots happy.



    I would go on to do some track testing of this brake deflector and it made a HUGE difference in both performance and brake system lifespan on track. With these in place and even just the stock brake cooling hoses the brakes just last and last, whereas before I was lucky to have a solid pedal after 3-4 laps. This C6 brake cooling deflector kit has been a solid seller and we should have a version tested and released for the C5 soon.



    The old pads were also heavily tapered, and with the DTC-70 pads that John from Hawk sent us on hand (he now works for Apex Wheels, and we've worked with him on some wheels for our track cars already) we rushed those into duty for the front brakes. Saved us having to rush some pads in for the next event!

    continued below
    Last edited by Fair!; 11-10-2023, 04:40 PM.

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  • Fair!
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    In Session 2 I heard weird noises under braking, and cut it short after only 2 hot laps, but found a half second to the 2:25.1 range (fixed a loose bolt after this session). Session 3 after lunch went a little better, with a 2:24.6. Still ways back in T2 class from Chris Wheelock (who changed classes to T2 for this event in his C6 Z06) and Cody Loyd (one of the owners at Apex who has an F80 M3 with MCS coilovers we sold him). Still learning this track layout and where to brake in this C6. Of course my AiM didn't work at all in session 3, so I have both no data and no video on that 2:24.698 lap. It wasn't great and you aren't missing much (I came back in early '23 in Koenig's C5 and ran a 2:22 with a non-functional 4th gear synchro, so it was just driving mistakes).



    Session 4 I finally had my head right, the video camera was working, and so was the AiM lap timer. I built a huge gap to the car ahead on the out lap and my first lap was looking great, much faster! Then 3/4 way through that long first lap, Anthony's C6 Z06 spun off track. I saw it happen ahead and I could tell he didn't see me coming, so I wasn't surprised when he pulled back on track right in front of me and blocked my lap (SCCA TT in this region does not allow "open passing" in TT, otherwise I would have driven around him). Even with that, plus backing way off to try cool down tires for lap 2, I ran that 2:26.2 lap above (the only one I got on video all day). The rest of that session was fubar, with 89F ambient temps and these damn Yokohamas getting greasy after lap 1.



    There were a lot more "heavily prepped" cars at this SCCA TT than I'd seen in the past - like Costas (red C5) and Anthony Jones (black C6) on full aero + Hoosiers in Unlimited 1 class - which were light years ahead of my times in our C6.



    Hollis was fast in his U1 classed 720S but Francisco's GT3 RS was only a tenth quicker in his Max3 classed entry. Still, finishing 10th place overall at an SCCA TT event was a new experience, and quite humbling.



    The final results are below left (click to expand, as always), where I ended up in 3rd out of 5 entries in T2 class - my worst showing in SCCA TT to date, and my first loss. One of the Max1 cars I usually compare to at SCCA TT events is Brian Phillips and his 2019 C7 ZR1 - above right. He is always on good tires, factory aero, AP brakes and knows many of the local tracks better than I do. He ran a 2:20 lap but I was a solid 4 seconds back - I've never been that far behind him, and have snuck ahead on tracks I know like the MSR 1.7 CCW.



    This loss really stung, so I spent some time back at the shop working with AiM Race Studio, then dug into that events' data (but without my quickest session 3 data, as I had an AiM issue). Observations show that my best "rolling lap" (2:24.1) was fully 1 second quicker than my best measured in those 3 AiM logged sessions. That is a continuous lap not using the start/finish as the delineation. Also my best "theoretical lap" (2:20.3) was 4 seconds quicker than my best timed lap - that means I drove fairly erratically and left a LOT on the table. I really have to learn the MSR 3.1 mile course better!



    The Lat/Long data was also pretty unremarkable, if not worse - the peak braking in 3 of 4 sessions logged was 1.12g, even with the new "big" brake kit and fresh pads. I was still getting significant brake pad fade in some sections, so we have more work to do. We loaded up to head back after another long hot day at the track, this time with only 3rd place points on the books. There was only one more event to go for the SCCA TT season, at ECR 2.7 CCW in November (another new to me layout I'm still learning). Having missed the first TWO SCCA events of the year and this 3rd place beat down, I was getting worried about season points...

    PREP FOR NASA TT

    We had a week to make some repairs and swap over to a set of Hoosier R7s for the upcoming NASA Time Trial at MSR Cresson. I wanted to see if the 295mm Hoosiers were better than the 315mm Yokohama 200TW tires - more data to crunch. We also looked at the front brakes, which had an alarming amount of pad wear after the MSR 3.1 event.



    One other observation was that the 315mm tire had worn through and kicked off our little aluminum cover plate at the fiberglass inner fender liner structure. Now with the added spacers needed to clear the Z06 calipers it shouldn't be wearing further, but I wanted some buffer here.



    The C6's coolant reservoir is the one thing that often gets worn into when the tire rubes on the left front - so we followed some advice I learned from a fellow racer at a recent autocross and we spaced the reservoir up 1/2".



    We had these aluminum spacers on hand for some brake cooling kits we sell, and that worked perfectly to move the reservoir up and away from the tire. This is a simple mod that anyone in a C6 should do if they are running wider front tires and have noted the inner fiberglass wear. We will come back later and re-make this aluminum patch panel and reinstall that.

    A SOFT SPOT FOR NASA TT

    If you have followed my build threads over the years you might remember that I was one of the early adopters to NASA Time Trial back in 2006, and we ran their Time Trial events almost exclusively from 2006-2019. Some of my best results were in TT3 class, which we dominated in the Texas Region from 2013-15 in this S197 Mustang, below.



    To make this pig a winner we ran at the LIMIT of the power to weight ratio, ballasting up to take advantage of P-to-W bonuses. We ran max effort aero, cut and flared fenders to runt he widest Hoosier A7s possible (335/345mm), had incredibly good brakes & ABS, and made the car easy to drive so a schlub like me could put it in the winners circle. In 3 years of NASA Texas TT events we had all wins with one 2nd place on a Saturday, but I came back on Sunday of that weekend and won. We also set 16 class track records, and our MSR Cresson 1.7 CCW record from 2013 of 1:17.250 stood for meany years (and our MSR 3.1 mile record from that car in 2013 still stands).



    We also ran most of our shop builds in a number of other NASA TT classes over the years, some with differing levels of success. What I have found is that the chassis you start with almost doesn't matter, so long as you maximize the power-to-weight ratio for a given class, ALWAYS run Hoosiers (and A7s where allowed), ALWAYS run the widest tire the class allows, and ALWAYS run the maximum aero the class allows. Whenever we neglected these lessons - that we learned on our TT3 S197 Mustang - we pay the price with lower competitiveness.

    NASA TT has no room for casual street cars with no aero, no power or weight misses, and running street tires will often get you laughed off the grid. We most certainly did NOT build this Corvette for NASA Time Trial, and it showed in our lone NASA TT event result, below.

    NASA TIME TRIAL, MSR 1.7 CCW, OCTOBER 30, 2022

    I wanted to run this event in the C6 in TT3 class, because that's the closest class where it fits - even if we built for SCCA Tuner 2 class with no aero and 200TW tires. I had a new set of 295mm R7s that I had scored for a great price, mounted on another set of 19x10" wheels, but that wasn't exactly a TT3 competitive setup these days. I really just wanted to just see my NASA TT buddies, and see how the C6 would do on R7s for the first time. Would it be quicker than the 315mm 200TW Yokohamas? The same? Slower? We would soon see!



    Due to the extremely busy month of track events and testing in multiple cars, I only entered a single day of a 2 day NASA TT weekend (Sunday) - which meant I would start at the back of the grid, as the rest of the field had a full day of lap times in the books to grid from. I had to get there early for a NASA TT log book and Annual Tech, but Hank passed the car with flying colors. We actually were pretty close on the TT3 class 10:1 pounds per horsepower ratio, which was just dumb luck.



    First session was REALLY tough, starting at the back of a 29 car field - behind a lot of TT4, TT5 and even TT6 cars. Needless to say I got a lot of passes in, but never had a clear lap - still finishing with the 7th quickest time out of 27 cars that ran that session - and that 1:21.0 lap moved me way up the grid. Of course TT3 was the biggest and fastest class of the event, with 7 cars (almost 1/4 of all TT entries were in this class!)



    Barely made weight after 1st session (+9 lbs over) so I added the cool suit cooler and topped off the fuel tank for extra ballast. Running the whole session still made me sweat, even at 51F ambient. In session 2 found a second, 1:19.962, only need three more seconds to catch the TT3 leader!



    After the 2nd session I was 8th quickest with only TTU and TT3 cars ahead of me. Blake Pomyyal's E92 M3 was out there topping the time sheets overall with a new TT3 class shattering record of 1:16.262, a full second ahead of my 2013 TT3 track record - the class has gotten stupid fast in the last decade!



    Session 3 was starting off well, but the R7s take 3 laps to come up to temp and that was a bit frustrating - as the front of the field would start catching the back within about 2-3 laps. I was fighting for a better lap as temps were rising, which might help these tires, when we saw waving yellow and black flags and we all had to come in. Turns out that two TT3 racers "had a moment" which cut that session short, and also cancelled the 4th TT session. So I would have to sit on that 1:19.962 lap from session 2 - which is 2 tenths slower than what we have run in this car in this setup on 315mm A052 tires. Hmm...



    Dan Parmelee's C7 Grand Sport was one of THREE cars in TT3 class that ran a nearly identical 1:18.2 time - 2nd through 4th places were decided by hundredths! Blake was way out in front with the TT3 win and track record, but I was way back in 5th out of 7 "in my own second" with that 1:19.9 crap lap. Sadly that time would have won TT1 or TT2, both faster classes, but that was just a lack of attendance. Oh well, it was worth a shot. Brakes felt like crap anyway - shocker - so new changes were to follow in the coming weeks.

    "HOOSIERS ARE ALWAYS FASTER THAN STREET TIRES"

    This is another commonly made statement that needs a LOT of caveats, as we have seen on multiple cars now. While I was disappointed that my best time on 295mm Hoosiers (1:19.962, NASA TT Oct 30th), it also couldn't beat my best street tire time on 315mm A052s (1:19.702, SCCA TT, Aug 13th). It is all pretty dang close, but I was expecting a 1 sec drop with the "purple crack", as we have seen in the past.



    And sure, the 20mm narrower 295mm Hoosiers being on a 19x10" wheel didn't help, compared to the 315mm A052s being on 18x11/18x12" wheels - yet another variable. In the end, when you compare the peak lat / long g trace data from my best laps on both tires, they are almost identical. Would an equally wide 315mm Hooiser A7 make more grip? Likely, but without infinite resources to test this theory, we'll just have to speculate.



    In the extensive "street tire vs race tire" testing we did in the 2018-19 seasons on our 2018 Mustang within NASA TT weekends - running 200TW Bridgestone RE71R tires on Saturdays and 315mm Hoosier R7 or A7 tires on Sundays - we showed a very consistent 1 sec improvement on Hoosiers. But the A052 has gotten faster than the RE71R, and a lot closer to the Hoosier in outright pace, and it sure heats up quicker than the R7.

    WHAT'S NEXT?

    I better stop here, as we still have a bunch left to cover for 2022 plus all manner of changes we made in 2023, leading up to a sale of this car that will happen soon.



    Next time we will cover the last 2022 SCCA Time Trial event (ECR 2.7 CCW) from November plus another NASA TT in the C6 in December. We also show a few updates with brake cooling (which made a big improvement!), a manually controlled muffler bypass setup, CNC ported heads / cam / intake / throttle body upgrade, new ARH Long Tube Headers / injectors / LGM carbon airbox / custom dyno tune, the carbon lip went back on, we had some paint work done to the car, then got it cleaned up and pictures shot for the upcoming auction.

    Thanks for reading!

    Terry Fair @ Vorshlag

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  • Fair!
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    For Session 2, Matt was gridded P1 and I was P2 in our Time Attack group of LA4-LA5 cars, but we agreed to switch places on the out lap so we wouldn't hold each other up (as his tires take many laps to come up to temp). It worked, and my quickest lap was on my first lap in session 2, but I was still .115 seconds off Matt's session 1 time, and I knew it.



    I was losing time in braking as well as driving, and this lap above is a hot mess - I almost went off in one right hander, trying to push braking zones. I made another attempt after this lap but was slowing down, as ambient temps were quickly climbing and the A052 tire does not do well on later, hotter laps.



    I kept going out in later TT sessions, and in each subsequent session I was quickest in each session, but with temps of 85F and climbing I couldn't improve upon my 2nd session. I needed to get my best lap done in the first lap of the first session, but gridding poorly really wrecked that one. The car had it - I just couldn't wrestle the time free. You can see the per session times below left, and overall results below right.



    Finished 2nd in class and 10th overall, a pretty poor showing. This event is where we found that the CSL programming was 100% hype, as the car braked with the exact same max forces as it always had. I was pretty disgusted, and mentioned the braking issues with Louis of GSpeed. He loaned me a special Continental / TEVES Mk60 ABS unit, which we tested the following week.



    We loaded up at the end of a long hot day, 2nd step on the podium behind Matt, who drove well and earned it. I was disgusted with my driving and the CSL nonsense. This event further proved that I had waited too long to upgrade to the Z06 brakes. I drank my mini-bottle of champagne and another FULL bottle to drown my sorrows - before pouring myself into the right seat of the F350, where Amy drove us home. We had another long, hot race day the next day, too...

    EQUIPE RAPIDE AUTOCROSS, LONE STAR PARK, OCT 16, 2022

    This was the first time we autocrossed the C6 and I finally convinced Amy to come with me and drive "her" car. The weather looked a bit iffy, with rain in the forecast, and Amy almost stayed home and slept, but I got her to go - then she beat me senseless in the car!



    Remember, this was after a long, hot day at the track where I drove and she didn't - so she was already in a sour mood. And then the rain rolled in and it poured all night, leaving the event site - Lone Star Park - a soaking wet mess. To run our first autocross in the C6 in the rain was a miss, in a car which she has said really was not "fitting her driving style". I just couldn't get her to run the car much on track, and now this?



    The courses here tend to be a bit quicker than other sites in the area, simply from the large layout of the site. Bunch of offsets and slaloms, so I figured a Miata would set FTD (and one did). We walked the course in the rain but right as the driver's meeting at 9 am kicked off, the rain stopped.



    After the clouds parted the sun popped out and turned the place into a sweat box, but it burned off the water on the surface rather quickly. Only a few Corvair club members got wet runs, and most of the first heat drivers had dry conditions. And Amy and I would run in the third and final heat of the day, after both working in the air conditioned timing trailer (win!).



    Amy and I both drove the C6 in CAM-S class, which was Amy's first autocross event in 4+ years. Now Amy has a few SCCA National Championship jackets in the closet, so I was confident she would pick it back up quickly - but damn, she even surprised me. After taking the first run with her in the right seat, she got out and let me take my 2nd and 3rd runs solo. My 3rd run put me in the lead and was - at the time - Fastest Time of the Day.



    The run group we were in was a bit too small and the 2 driver cars had to hustle to switch drivers before the next run, and our 6-point harness setup didn't help. So Amy opted to take all 6 of her runs back to back - to avoid switching the seat / harnesses back and forth between drivers. And that worked for her, with warm A052 tires and me tweaking the shocks and tire pressures for her as she just pounded out some amazing runs.



    By her 4th run she had beat my 3rd run time, and kept finding time. Bam, Bam, Bam! She was flying, and her 6th and final run of 51.0 was 2nd quickest of the day in the final tally. She then handed the car over to me to take my last 3 runs, and I scrambled to get into the car and quickly got to the line.



    OF COURSE IT STARTED RAINING, and I made my last 3 runs back to back with the wipers on high. I was literally the only driver in the final heat to get wet runs, but thems the breaks! Amy's best run is shown below, but my laps in the wet cannot be shown due to the unending stream of expletives.



    Results - Amy dominated the CAM-S class and won by .7 sec while I slogged around in the rain taking 2nd. She also took Top PAX for women and set 2nd fastest time of the day, and since the ER club pays out money based on PAX finishes, she walked away with a fist full of cash. This event and win totally turned her day around, from sleepy and grumpy in the rain to a money winner, that's for sure!



    The C6 drove really well, and the brakes worked pretty good here at these low speeds. All I did on my first run was drag the brakes while going from grid to the starting line, and they got warm enough to work fine on my first run. I suspect this car could be a really good CAM-S autocross car if someone wanted to do that with it.

    MK60 CONTINENTAL/TEVES ABS UNIT - FAIL

    Louis at GSpeed loaned me a Continental / TEVES special Mk60 unit, which apparently has some higher braking thresholds. It was supposedly a "plug in swap", but it 100% is not. This requires a special wiring harness, which we found out the hard way. These are not inexpensive units (four figures) but if it could improve the braking of this car, I'd buy one. This was a loaner from the weekend before so the next week we swapped it in place on the C6 and proceeded to try to get it to talk to the car.



    This is another internet hyped Mk60 upgrade which we found out does not work with the same harness as the "regular" Mk60. I wasn't going to order another $1200 harness then burn the hours it needed to install that all to test a borrowed ABS unit.



    Lots of programming attempts, phone calls and emails, but in the end - a fail. We removed this unit, reinstalled the original Mk60 ABS brick, and got to work on the Z06 BBK install.

    C6 Z06 BIG BRAKE KIT - INSTALL

    After giving up on finding any magic in the Mk60 units, with programming or special units, it was beyond time to finally time to move forward with the J56 (C6 Z06) brake upgrade on our base model 2006 C6 Corvette. Why? Because the braking forces have not improved with any change in tires (275 RS4 vs 315 A052), pads (stock to R12 to R16), calipers (JL9 to J55), rotors (JL9 to Z51 to Z51 smooth), or Mk60 calibrations (base vs CSL). This car always stops at the same 1.15 to 1.17 peak, period. It's smooth, it's safe, just not changing.




    This is a system I looked at early one and it uses a 6 piston front and 4 piston rear caliper designed by PBR. Normally these use small brake "padlets" for every piston - yes the stock Z06/Grand Sport used 20 brake pads. But everyone that makes pads has gone to a normal "unipad", and that seems to work better.



    In hindsight this was probably the FIRST mod we should have made to this car, and the prices above are amazingly low compared to the typical BBK - which can be $3000-5000 per axle. I wasn't keen on spending $10K on brakes on a car that had a non-functional ABS system, so I decided to fix the ABS first... and that dragged on for what, 18 months?



    Again, this set had the front calipers rebuilt but needed a little more effort to actually make them work - the dust seals at each front caliper were pooched out a bit. Brad handled that and got all 4 corners swapped out with new G-LOC R16 front and R12 rear "monopads".



    I had purchased one new "smooth" (not cross-drilled) front rotor from a Z06 early on, and it was only 10mm larger in diameter but nearly 5 pounds heavier than the Z51 rotor. There are some big chunks of 3 weights cast into the Z06 rotor, which we thought about machining off. But in the end we left it alone - don't want to alter too many variables at once here. The old Z51 calipers and pads were used up and were tossed in the recycling bin, but I kept the old calipers.




    When we ordered these Jongbloed 3-piece wheels we erred on the side of caution and ended up needing a spacer at both ends to clear the inner fenders. We do this on one-off sets sometimes as there's no way to make a "negative spacer", so we make our best calculated guess and then pull the wheel in 5mm more than we think - to avoid poke - and we can always slip a spacer in to move it back outboard. Well the Z06 calipers are MUCH thicker than the Z51 2-piston sliders, so we needed an extra 5mm front and rear now, for the inner spokes of these wheels to clear the calipers. The 19x10" wheels need the same 5mm spacer, too.



    I wasn't going to change all of the calipers and NOT change the master cylinder, so a rebuilt J56 master cylinder was ordered and installed at the same time. It was bench bled before going onto the car then bled when the new calipers and lines were installed.



    I mentioned the "missing" rear 4 piston caliper, which was in an unopened box but I guess the delivery folks perfectly opened that one box and took it out and re-taped it. Anyway, I had to buy a new one to replace that, was sent the wrong side, but it was easily adapter to the correct side by moving the bleeders and crossover tube. The last thing we learned was that the brake JL5 lines are the wrong length so we ordered J56 length stainless lines and managed to get it all put together before the next weekend's Time Trial.

    HIGH TEMP TIE ROD BOOT REPLACEMENT

    One side project that happened during the J56 brake upgrade was replacing the outer tie rod boots with high temp silicone units + some custom stainless steel heat shields. These boots were ordered a while ago and took 3 months to arrive from Eastern Europe, but it was worth the wait. Jason had made some measurements, found these boots, and they actually fit!



    If you remember we have burned up tie rod boots continuously on this car, with both the Z5 brakes and it was likely to happen again with the Z06 brakes. The outer tie rods at both ends of the car are sitting right next to the brake rotor, which we have measured 700F and higher temps from.



    The replacement outer tie rods were already burning up the new boots - and we never could find OEM replacement boots. These silicone versions were a lot less costly than all new tie rods and should survive better at higher track temps. But we also made new stainless steel heat shields at the same time. These are made from thin 316 SS sheet that sit between the securing nut and the spindle, then droop down over the boot and create a thermal shield between the rotor and boot, with an air gap on each side.



    The new tie rod boots and stainless steel heat shields were installed at both the front (above left) and rear (above right) ends of the Corvette. These have worked wonders and half a year later they still look new! This is the new fix for tie rod end problems.

    HAWK SENDS MYSTERY PACKAGE

    I have been known to promote some brake pad brands over others, but it is because there are clearly different tiers within brake pad offerings' prices and lifespans. I may have built up some biases over the years after having "less than great" results with certain lower cost brands. We tested a number of pads one year on a heavy S197 Mustang track car using Hawk, Porterfield, Carbotech and others. The Hawk HP series street pads were strangely popular within track groups for a while but we could melt them to goo after only a few laps.



    As much as you see here on this forum, I post even more on my personal Facebook page daily. A friend from there, John Butler, worked at the US distributor for Hawk and noticed when we switched from the Z51 to Z06 brakes and sent us a "care package" that included both front and rear brake pads for these calipers.



    They also included bottles of their HP660 brake fluid, lots of swag, and a funny note! I gave them a thanks and shout out online, but didn't think much about it for a while - but this will come back later as a much welcomed gift that was nice to have for testing on this car (we eventually used ALL of these pads and the brake fluid!)

    SCCA TIME TRIAL, MSR 3.1, OCTOBER 22, 2022

    October got pretty nuts and between this car and a customer's car I spent 4 days on track + the one autocross, so it was beyond busy. This was an SCCA Time Trial day at MSR on the 3.1, which I had earlier done the Apex HPDE and some sim time to try to learn. None of that seemed to help as I had another poor showing here, and suffered my only loss in an SCCA Time Trial in this car!



    Again - THIS is the series we are trying to win for the season in this car, so we had the car on the "big" brakes, fresh tires, and I hopefully knew where I was going now and could improve upon the dismal 2:28 lap that I ran with Apex earlier. The "fuel starve" thing never did pop back up, so that was a relief. There were some teething pains with the new brake kit, but a little pit side repair got everything sorted.



    Amy took photos at this event and its nice to see that we have removed the massive brake dive with proper spring rates (above left). Also, the "you are running too much camber" folks had to shut up when I show these laterally loaded images in the fastest corner of the track (above right), where all of that static negative camber disappears. In a perfect world I would run even more camber than what we could reach with the custom offset shims!



    My first session lap wasn't exactly setting the grid on fire - I just suck driving on this 3.1 layout. I also forgot my Micro SD card, so video was down for most of the day (I borrowed a card for the 4th session, which we show in the video below). I was a bit disappointed in the fact that upgrade to Z06 brake rotors / calipers / hydraulics and pads made little to no differences in stopping power.

    continued below

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  • Fair!
    replied
    Project Update for May 31st, 2023: I waited to long to update the build thread so I broke it up over a couple of weeks. In this post we cover build progress, TT competitions and even an autocross from August of '22 through October of '22. We also began to wind down development work, as we were quickly approaching a line where further mods would move this 2006 Corvette into "race car only" category - right now it is still a REALLY nice street car.

    ​​

    The 2022 competition season was very hectic and this C6 gave me and Amy a chance to get back on track and gain more experience with some new course layouts we had missed during our hiatus from Time Trial competition during the worst of the Pandemic (2020-21). I drove the C6 at 16 of the 30 events I entered last year, which are shown below in a partial screenshot of 2022 events from our "racing events" gallery (there were events in December not shown).



    This C6 allow me to spend a lot of days at the track, and it was glorious, even if we were still fixing issues along the way. This Corvette was always meant to be a "temporary" track car for Amy and I, and as the season ended last year we wrapped up our track driving in the C6 - as both of our "real" track cars were finally on hand and ready - so this Corvette is going away soon. I will talk more about in the next series of forum posts.

    OUR "REAL" TRACK CARS ARE HERE

    This C6 was always purchased to allow us to get some seat time until our two "real" track car builds were complete. Originally we had planned to finish Amy's 2013 FRS with an LS swap, but instead we ordered her a 2023 BRZ, which arrived in late November 2022. It now has MCS remote doubles, bushings / bars/ control arms, 18x10" wheels / 275mm tires, racing seats and a lot of other mods for SCCA Time Trial T3 class (as well as Solo STR and NASA TT4), where it is faring well.



    My 2015 Mustang (above right) was running in January '23 and now has an HPR built 454" LS7 dry-sumped engine, which is about to hit the track to fulfill for my competition needs for the foreseeable future. These two cars sort of book end the performance of the C6 - with the BRZ at the lighter end with 250 hp and the Mustang being the bonkers 800 hp car with full aero at the other end. And while it would be GREAT to keep the C6 as our back up track car (I lobbied hard for this, but lost that battle!), we need room at the shop. Now let's cover some of the C6 build!

    C6 Z06 BIG BRAKE KIT - ACQUIRE PARTS

    The struggle I went through with the brakes on this car could fill a sizable book, and I never felt like we had a great "BBK" upgrade to shoot for. The better aftermarket solutions are $4000-5000 per axle and all have some downsides (cost, noisy 2-piece rotors, wheel restrictions, loss of parking brake, etc). After spending too many hours to count looking at options, we decided on the C6 Z06 OEM brakes, with a few upgrades. These are 6 piston front / 4 piston rear and have rotors that utilize the same parking brake shoes as the base car - so we wouldn't lose the parking brake functionality like some BBKs do.



    A friend I knew from college had a "complete" set of used calipers, pads and rotors and I pulled the trigger on that deal. The front calipers even had upgraded stainless steel pistons. Of course, like many "deals" turn out, one of the boxes mysteriously showed up without a rear caliper in it - so I got to buy a new one to fix that situation (at which point the cost savings got a lot worse).



    The rotors were worn but not terrible, but one of the used ones had some deep grooves and was replaced with more "non-cross drilled" smooth units. Of course we ordered new R16/R12 G-LOC pads for use when these went in, a few months later. Why wait? I had more ABS testing to do first, namely the much revered "motorsport" Mk60 programming I wanted to try, before we swapped to the bigger brakes. So we kept the Z51 brakes for a a bit longer (too long, in fact).

    FRESH TIRES ARE ALWAYS FASTER!

    The Yokohama A052 was hard to get in 2022 - because it was the fastest tire in the widest size (315mm) for bigger cars, so back in late August '22 when a set came back in stock I jumped on it.



    These weren't installed until October, as the last set was still winning events. I wanted to get through the Mk60 testing, then the BBK, then put the $2000 set of A052s on for the SCCA's Fall Time Trial events.

    MACHINING OZ RACING 18X11 WHEELS TO FIT C6

    I am a wheel junkie - there should be a 12 step program for people like me. Even with four sets of wheels for the C6 now, I felt like we were missing a backup set of 18x11" wheels. Honestly, this would be an ideal set to use for 315mm "scrubs" at practice events, and keep the "fresh" 315s for actual competition events. The two sets of 19x10" wheels were showing their limitations on width, and only having one set of $4400 Jongbloed 18x11/12" wheels...



    Jason and I poured over wheel catalogs looking for the oddball offset that the narrow body C6 needs, and our buddy Nate at Tire Rack found some good deals on some OZ Racing 18x11" flow formed wheels - lightweight, had the wacky ET75 offset we need, and the right bolt pattern. Two were on closeout at a great price but they were gold, then I bought two more black wheels at full price - still a savings! bought this set in late July, but in August when we went to test fit them we found they had the wrong hub bore... too small.



    Luckily we have CNC machines and our crew dialed these in, so in early September we had 4 new 18x11" wheels with the right offset and hub bore, but two different colors.



    I planned on getting a media blast cabinet soon after, to remove the gold and black finish, then have them powder coated in the iconic Bengal Red that we had the Jongbloed wheels done in. We already have wheels and tires for many projects all over the shop so we boxed these back up and put them up stairs in storage. Then I got really busy in the Fall of 2022 and kind of forgot about these wheels - until I literally started doing this write-up in May 2023! Too much going on to keep this "temporary" track car in my brain, I guess? Now that we do have the blasting cabinet I might get these re-done and sell them.

    ISSUES WITH SLP COLD AIR

    The SLP Cold Air kit for the "LS3" Corvettes never fit this car well, and after many events we would notice that the plastic section that goes over the radiator would POP OFF from the silicone adapter that bridged between the 90mm throttle body and that cold air section. This isn't helping the tuning one bit!



    This was finally fixed with a bead of epoxy at this joint - covering the joint shown below right. In hindsight I never should have bought this "cold air kit", as it caused more problems than it solved. A proper metal sleeve inside was likely the better answer, to give some rigidity to the plastic for the silicone hose coupling to clamp to.



    While this never came apart again we ended up replacing this entire system with a carbon cold air kit from LG Motorsports in 2023.

    APEX HPDE, MSR 3.1, SEPT 10, 2022

    We loaded up the C6 into the trailer on September 9th with the old set of A052 tires, as this was just going to be a "practice" event for me. APEX had an HPDE event where they were running on the MSR 3.1 mile course, and I wanted to use that to get familiar with the layout for an SCCA TT we are running there in a month.



    Brought my buddy Erik Koenig from HPR along with me to ride along in a session, too. I haven't run the 3.1 mile course since 2013 (where I set the TT3 track record at 2:22.7 - which still stands), so I was a VERY rusty and struggled to find lines and string together a good lap, even with some simulator time the night before. It was a big challenge to remember all 16 turns (its really about 23), plus the rough transition sections going from the 1.7 to 1.3 mile courses, too.



    We got there before dawn, unloaded, and got the C6 ready. The driver's meeting was still distanced here, towards the end of the Covid Pandemic. This group has a Time Attack series in addition to their HPDE events, and we ended up sponsoring their Apex Lap Attack events for 2023.



    For the first session I gridded P1 and didn't see another car until lap 4, which was great. Erik was riding shotgun with me and we took some "fun laps" in that first session, where I used the cool shirt system wearing my full driving suit, which was nice.



    I was fighting with the brakes overheating and once I caught traffic after hot lap 3, we came in. The brakes felt sketchy into Turn 11, Ricochet, with the long straight before that from Turn 10. Felt like I was losing booster vacuum, so I had to use a LOT of pedal effort and brake early. I had a fairly lackluster 2:28.2 best lap on lap 4, but that was with a passenger, and we were just feeling out the track. Added some fuel (double the fuel load I ran in the 1st session) and gridded up early for session 2 to look for some real lap times.



    Session 2 started out fine, leading the fast group out again, taking it easy on the out lap. But as we took the green flag and I went into the tight 1.3 section, the car suffered what felt like a massive "fuel starve" issue in the Turn 8 (Hairpin). The engine would simply LAY DOWN with zero throttle response for about 4-5 seconds after that corner, leaving me a sitting duck. Made a couple of laps like this but I was holding people up, so I let folks by and came in. Clearly this was an electronic / tuning issue, as the fuel load was too high to starve.



    Spent an hour wiggling connectors, scratching my head, and texting with tuners - but could not find any issue. And this time the SLP cold air tube was finally not popping off. The fuel tank was well over half a tank, and it never did this in the 1st session. Super frustrating



    Engine oil and power steering fluids looked great, with minimal fluid at the power steering cap catch rag. We ate some lunch, loaded up and left early - instead of going out and repeating the issue over and over. Weather was perfection (66F 1st session, and 75F for the 2nd).



    Watching the video when writing this (after running it in later events) it is painful - almost didn't post the video. Frustrating day with not enough running 7 laps!) to learn this track well, and then this new "fuel starve" situation, and the brake heat issue was getting a bit ridiculous. If you read further you will see that we had the car a LOT faster on the 3.1 mile course in the October SCCA TT here but I had even more poor luck that held back times. anyway, this September HPDE was a bust - back to the shop!

    ADDING "CSL" PROGRAMMING TO Mk60 ABS

    I noted some pretty abysmal braking at the Apex 3.1 event above, and I was looking for something to blame. I wasn't ready to throw the "big" Z06 brakes at the car just yet, as I felt like there was still some room to improve with the 2005 era BMW ABS programming. And having read about "CSL" programming and worked with a few folks online, we attempt to "program" our plain jane Mk60 ABS. We had an Apex Lap Attack event coming up on the MSR 1.7 course, too!



    Alas, adding the CSL programming wasted a lot of time and we eventually got it to "take", with a lot of testing, sensor programming, and even a custom config file. That last bit took some outside help - and someone from the ABS Swaps and Hacks FB page we created wrote a custom config file to make our Mk60 ABS unit take the CSL program.



    We tackled the pressure and yaw sensor calibrations, which were additional steps that we were told "well of COURSE you are supposed to do that!" - it had zero effect. The CSL programming had zero effect, too - with street, track and autocross testing, as stated in the video below.



    Honestly this is another case of "internet hype > reality", and after talking to a few other "less vocal" racers who have tried this on swaps they all admitted the same thing - this doesn't do squat on a swapped Mk60.



    Again, the CSL programming had ZERO effect on braking g forces or stopping power. In both street ABS tests and track testing we noted the same 1.15 to 1.17g stops, before and after. In this same time period we completed some track testing on the wide body E46 M3 we built for a customer (above right), which we also performed a Mk60 swap on using the same sensors and wiring harness - and that car stopped at 1.31g. Granted, it had a lot of aero and 335/345 Hoosier A7s, but the lateral Gs were similar on both cars. I don't think the C6's A052 tires are holding it back (we tested with a new set also), as the lateral forces far surpassed what it could manage under braking. DON'T WASTE YOUR TIME




    For as "easy" as this Mk60 ABS swap is supposed to be for modern GM cars, it sure is seems limited (we will have data on the CTS-V above, which we also Mk60 swapped). Every time I drive Koenig's C5 that we swapped to an S197 Mustang ABS, I regret choosing this Mk60 swap on our C6. Sure, the S197 swap is a good bit more work, but it actually WORKS better. The ABS programming scheme and technology is a decade newer and it shows. I won't make this mistake again. Sure, it works a LOT better than the GM ABS that came on this car, but it could be... better.

    FRESH TIRES, RESET FOR NEXT TWO EVENTS

    While juggling customer cars and track tests, we managed to get the C6 into the shop days before the next competition event to look things over, fix one tiny leak, and mount up those fresh 315/30R18 Yokohama A052 200TW tires onto the Jongbloed wheels.



    Then upcoming Saturday event was with a new (to me) series (Apex Lap Attack) at my favorite track (MSR 1.7 CCW), which would be the last time I would compete on track in this car on the old Z51 brakes. We also signed up for an autocross on Sunday, with Amy co-driving. This two event weekend is where we would get some test data on the CSL programming.

    APEX LAP ATTACK, MSR C 1.7 CCW, OCT 15, 2022

    This was the first Time Trial I had done with this group, which they call Apex Lap Attack. I drove the 2006 C6 in this event in their LA4 class (LA1 is fastest to LA5 is slowest), and they have some damn fast folks out there running big aero, Hoosiers, big tire and big power! Some folks only run this series and build for the classes better than me, who just showed up and was classed when I got there.



    Amy agreed to join me and helped me during this warm October day - "super genius" me had removed the cool suit cooler since it was "Fall" and I "wouldn't need it", which was a mistake. We got to MSR at dawn, unloaded, checked in, added their unique number boards, and realized I was in the wrong class - they re-classed me to LA4. An old autocross friend of mine Matt Dasheill was there in his E46 M3 on Michelin slicks in the LA4 class, and I wondered how quick he would be?



    First session I gridded poorly on sticker A052 tires but was stuck in traffic for the first FIVE laps. My first session time of 1:20.013 was done on lap SIX, which was 3 tenths slower than a month earlier 2 year old A052s. Went out twice in this session (out for 3 laps, came in to bleed pressures, found a gap, and went for 3 more laps) to find that lap. Matt put in his best lap on lap FIFTEEN in his E46 M3, when his Michelin slicks finally warmed up and switched on. He had me by 3 tenths... but I've run that time before, back in August...

    continued below

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  • Fair!
    replied
    Originally posted by DrinkinPepsi View Post
    Have you looked at the ST3 seat from Marrad Industries?


    I have an 06 and I'm headed down this path from AutoX.

    I have brake ducts, Dewitts with oil cooler, Z06 PS cooler. Koni adjustable shocks and Z51 conversion suspension and brakes, Strano Front Sway

    I'm really looking at
    1. seats/ harness
    2. 18x11 square setup
    ​​​​​​3. MCS
    Do you think that is the correct order? Is there something not on that 3 that should be there instead?

    Haven't seen that seat - i will check it out. As for your modifications / order, it looks proper. I'd hustle my way down that list - the tires and coilovers are the biggest payoffs!

    Leave a comment:


  • DrinkinPepsi
    replied
    Have you looked at the ST3 seat from Marrad Industries?


    I have an 06 and I'm headed down this path from AutoX.

    I have brake ducts, Dewitts with oil cooler, Z06 PS cooler. Koni adjustable shocks and Z51 conversion suspension and brakes, Strano Front Sway

    I'm really looking at
    1. seats/ harness
    2. 18x11 square setup
    ​​​​​​3. MCS
    Do you think that is the correct order? Is there something not on that 3 that should be there instead?


    Leave a comment:


  • Fair!
    replied
    continued from above



    This ball valve is at the bottom of the engine bay and is drained after every Time Trial or track test. The above right image shows how much comes out after 4 track sessions (after the August SCCA TT). Just a few ounces of clean Motul oil - no water, no grit, nothing to be alarmed about.

    CHASSIS TIRE RUB + TIRE SHIELD

    After this round of work above - which spanned more than 3 weeks, I had our guys put the Control Tires back on. I wanted to street drive the car for a bit, and I did. These little 275s fit so well, even with 10mm spacers at all 4 corners. But when the Yokohamas went on I showed Doug where I had felt tire rub at the last TT event...



    I could feel some slight tire rub on the left front in a brief street drive before loading the car into the trailer last time. I asked about this online and multiple Corvette C5 and C6 owners noted the same thing - 1) these cars aren't exactly super precise and 2) it is common for one side's front tire to rub and not the other. Most folks just let it rub through until it stopped wearing, but the coolant reservoir is right behind this spot and I didn't want to take that chance.



    This spot above was worn completely through - so I asked Doug to make this aluminum patch panel to install over the hole on the Left Front (the RF corner had NO rub).



    This was held in place with special expanding rivets made for composites, and with minimal rivet heads in the way of where I was sure the tire would once again rub. This was something I would be keeping an eye (and my nose) on for the first TT session the next day. This was the last bit of work on that Friday before I loaded the car into the trailer for the TT on Saturday.

    SCCA TT @ MSR 1.7 CCW, AUGUST 13, 2022

    Amy and I arrived at MSR Cresson at 7 am, and the event was running the same 1.7 CCW course we do ALL of our testing at. This would be my first SCCA TT event in this C6 at a track that I actually know (I have 500+ laps here over the last 20 years), unlike the last two events at ECR, where it was a new to me track. I was still struggling to learn ECR, even after hours on the sim rig.



    Luckily I do not need sim rig time for the MSR 1.7, in either direction. I was hoping my familiarity at this track and SO many track tests in THIS car here (11!) might mean we would not only win T2 class (for a 3rd time in a row?) but possibly move us up in the overall rankings. If it were not for one mega race car showing up, we might have topped the results sheet...



    I had hoped to take the C6 out to Cresson in the days above to do some test laps, but we simply ran out of time. All of these changes to various plumbing systems made me super nervous that something would happen on track and I'd be spilling engine oil, power steering fluid or coolant. Luckily the C6 did not leak a drop all weekend. Whew!


    ​​
    For the first TT session's "free-for-all" gridding, I lined up in grid early sitting in what I thought was P2. This was to keep from getting caught behind slower traffic on the out lap. But it turns out I was in the the wrong line at grid, so I went out in P10! Figures... This first TT session at 8:45 am was only 84F ambient and I didn't want to waste it, so I picked off a few cars in the first 3 laps and finally got a clear lap on lap 4, in which I ran a 1:21.0 (a new best for the car, but only just by a tenth). I took a 5th lap and it was slowing down, as these A052 tires like to do their best on lap 1.



    On the very first lap I could smell and feel some tire rub, but after decades of doing this I could tell (mostly from my nose) that it wasn't "real bad" so I went ahead and finished that whole session. I came in, jacked up the car, and removed the LF tire... Sure enough the 315mm tire was rubbing on the new "shield" that Doug had built to cover up the wear noted on the fiberglass inner structure. I figured this would happen.



    I added a single 1/4" spacer to that side to space the LF wheel away from the inner structure, but nothing to the right front. And it worked - didn't rub a slight bit for the rest of the day. The LF tire now has the slightest hint of poke while the RF wheel tucks nicely under the fenders. So the asymmetric spacer setup will stay for the time being.



    I was worried that our typical August summer heat in Texas would derail my plans for a fast lap in later sessions, and session 2 was at 10:45 am... but luckily it was still 84F outside for that one, and I was now gridded P4 (by times). I had a feeling there was a 1:19 in the car, so I let the car in front get a full 1/4 mile ahead of me on the out lap, then threw down a blistering 1:19.8 on my first hot lap! I caught the car ahead on the 2nd lap so I blew it off and came in. Super happy with that time - a new personal best for this car here! This is what I should have run at Track Test #11 but the lime on the asphalt wrecked those chances back in July.



    That lap time moved me up to P2 overall and in grid, with the only other car under 1:20 laps being Mike Dusold's tube framed, twin turbo Camaro - he was running it with the Michelin soft compound slicks and their Pikes Peak high aero package, and he was flying.



    The lap above from session 2 was my quickest up to that point, and the most entertaining lap in the car in a LONG time, so that is the one I made the video for. As I noted in the beginning of the video, the Coolshirt cooler was working WELL and we used the same bag of ice all day. It was AMAZINGLY cold and I cycled it on and off until I got going on the hot lap. I also felt like "there's a second left in the car" after my first session, and I told Amy that morning that I'd keep taking laps until I ran a 1:19.



    Amy got some good pics we have since used to analyze the camber and body roll, which is down from before the alignment and swaybar changes. The oil temp issues are a thing of the past with the highest oil temp seen all day of 245F. The coolant temps did climb up to 214F for a high, which is higher than before the oil cooler - but this is to be expected when you have to stack coolers - yet 214F is still fine. That 1:19 lap leap frogged our C6 ahead of the fastest cars from the previous two SCCA Time Trials, including this C7 ZR1 on AP brakes below right (who was quickest at both the June and July TT events).



    I didn't think I could improve on the 1:19.8 time so I let the SCCA RE Matt Lucas take a session in the C6 for fun in an HPDE session. He had a ball and said "this was the easiest car I've driven on this track!" (it was his quickest). But after eating lunch we still hadn't loaded up the C6, and with just a few minutes before our TT group was called grid I hopped in and rushed up - and with Dusold gone I gridded P1. This would ensure I got a clear first lap without traffic, no games needed!



    Even with 92F ambient temps and climbing track temps, my first lap in session 3 at 12:55 pm was faster, with a 1:19.702 - nearly a tenth quicker, even with the higher temps. My session 2 time of 1:19.800 had a pretty big driving mistake into Turn 4 (Buzzard Neck), fighting these underwhelming brakes. I swear something is forcing me to brake 100-200 feet sooner than the S550 from before, and it is costing us major time.



    With the fastest time of the 3rd TT session I was confident we had secured the T2 class win of 4 cars, and it did. Even with more sessions later in the day that 1:19.702 was still 2nd fastest overall, and the fastest street car and fastest car on street tires. If you expand the data trace graph above you might notice that this even saw our highest peak lateral grip numbers (1.53g spikes, 1.3 sustained) but the same 1.17g braking we have seen since back when we ran the RS4 tires.



    After that session I was thoroughly exhausted and we let the car cool off for a bit before loading up and leaving early. Other than the brakes and my driving mistakes in session 2 (and not lining up in the right grid line in session 1) I was very happy with the performance of the car. It felt good to put the car everyone said "why would you ever race that?!" out in front of everything this side of the 1200 hp Pikes Peak race car. And we still had time to find - I am not done with these brakes!

    BRAKE CALIPER AND WHEEL TESTING

    Having just the one set of 3-piece Jongbloed wheels for our only "race set is a bit worrisome. What if I go to a competition event and get a flat, or worse? Sure, we have the two cheap sets of FlowOne 19x10 wheels, but just the one set of 18x11/18x12s for the 315 A052 tires. I want a spare wheel and ordered a fresh set of 315/30R18 A052s the DAY they came back in stock - the set we have been running were purchased and I have been running them since 2020!



    Buying another $4400 set of Jongbloeds and waiting 3-4 months to get them is not really my idea of fun, so I tagged in my account specialist at Tire Rack to peruse through their catalog looking for an 18x11" wheel with 5x4.75" PCD and the wacky backspacing we needed. I gave him a bunch of numbers and he spit out a few options, but really just one set worth using - these 18x11 O.Z. Alleggerita HLT wheels, with 2 in gold (at closeout prices!) and two in black.



    Well we missed one specification to give him - the hub bore! So we will need to machine just a kiss from the inside to get them to bolt onto the C6, but the offset was dead on for what we want. Sure, its not 12" wide in the rear, but they should work fine for the backup "scrub" set of A052s, with the fresh set going onto the Jongbloeds. Look for more on this soon, when we get some time on our CNC mill to do this step.



    I have been complaining about the brakes on this C6 since Day 1. The JL5 base brakes are just not adequate, and even upgrading to the Z51's J55 brakes only changes the diameter of the rotors. The circa-1984 PRB sliding calipers are still limiting this car, and I can watch them flex just when we are bleeding the brakes. The pads wear at a taper, too. So I did some looking and found some J56 (C6 Z06) fixed calipers in the 6 piston front, 4 piston rear sizes. We test fit the 6 piston front with a new smooth 14" (355mm) Z06 front rotor and it just cleared the wheels, whew! Look for more on this in the next installment - along with some real back-to-back and data logged testing.



    Lastly, there was an issue with this SLP cold air kit. The plastic portion keeps popping off the silicone hose that attaches at the throttle body. So that was cleaned thoroughly and epoxied together at this joint. We will see if this stays in place and if not, we will source another cold air kit.

    NEW MGW SHIFTER

    With the gearing internal to this transmission and rear gear ratio we are stuck with (3.42) the C6 is often needing 2nd gear. I've fought with the 2-3 upshift so many times that I started avoiding it - didn't even attempt it at the SCCA TT event in August at MSR. I ordered a new MGW shifter a while ago but it got here right before the August TT, so we installed it the week after.



    Now I'm not one to blindly buy and install aftermarket shifters on EVERY single car I drive on track, and it is more rare for me to do this. But after so much trouble with this C6, and such good feel with the same shifter on Koenig's C5 (which I have autocrossed and tracked in the last 2 years), it was time.



    CORBEAU EVOLUTION X VS CORBEAU SPORTLINE RRS SEATS

    It is no secret that fitting a seat into any C4/C5/C6 is a real challenge. We ran into this on my C4, on Koenig's C5, and again on this C6. This Corbeau RRS reclining seat was a huge compromise for the ability to allow Amy and I both to drive the C6, with a slider to go between our vastly different heights.



    We have revised these brackets so many times I hate to think about it, but they finally slide forward and up for Amy, then down and back for me. But due to the constraints of the C6 interior and the fact that we NEED to have a rear bracket to mount the anti-sub and lap belt harnesses (see below left) it makes for an imperfect seating position for me.



    It is hard to show this but I am lacking about 1" of rearward movement compared to the (terribly flat) OEM seats. To fit my head under the roof I then have to tilt the seat back a lot, so my legs are too close to the dash and my back is leaned more than I like. I barely fit in this car - its like "Miata with a hardtop" difficult for me.



    Reading a UK C6 racer's blog I stumbled upon a seat that promises to be made to fit the C5 and C6 Corvette with a narrower / thinner seat back, NO TILTING, but a built in back angle that "fits most drivers". This was too good to be true so I checked with Corbeau, they said it was a better seat for the C6, so I ordered a pair and we got to work.



    Comparing the Evolution X to the RRS they do in fact look very different, even if they are likely built on the same steel tubular frame. The Evo X has a lot less bulk in the back portion, and Doug was able to bolt that in with the Corbeau sliders and unique Vorshlag bottom mount brackets and harness mounts.



    Well... for my body, it was worse, not better. The tilt angle was too vertical and it did not in fact slide back further. This was discouraging and a waste of time for our project, but Corbeau let us return the seat (it sat in the car for all of 10 minutes) and we only lost shipping costs both ways.



    A little musical chairs and both seats were back to the RRS norm. We could put a "race" seat in this car and possibly find some room, and we have done that briefly - we talk about the seat mounting challenges of the C5/C6 Corvette in this new forum post.

    WHAT'S NEXT?

    Yikes, this "quick update" got really long, but we are finally caught up to real time! We have the J56 brake upgrade happening soon with new G-LOC mono-pads and some missing parts from the kit I ordered inbound. I had signed up for an SCCA autocross with this car but wee cancelled at the last minute when we saw a weird course design (which proved to be wise - it was an event plagued by delays on a very hot August day).



    We will run this C6 in CAM-S (or XS-B) autocross class, and several more Time Trials in the coming weeks. I had way too much fun in Koenig's C5 (above right) over the past couple of years, and I think this C6 is closing in on the performance of that car. We also have parts inbound to finally add the "Continental" program to the Mk60 ABS, hoping for more braking force at the limit. Its either in the calipers or the programming! Amy is finally going to make some laps in this C6 again soon as well.

    Thanks for reading,
    Last edited by Fair!; 08-31-2022, 11:36 AM.

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  • Fair!
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    COOL SUIT COOLER MOUNTED + WIRED

    We started this install before the July SCCA Time Trial event above, but a borrowed cooler's pump was dead so we had to punt for that event (GROAN). Coolshirt.com makes 3 sizes of coolers with internal pumps: 13 quart, 19 quart and 23 quart. The middle size is the most popular and what we built around. The smaller one fits tight confines and the bigger one is more suited to longer stints like endurance racing.



    I had our crew make a mounting tray to show off our fab skillz - don't do this! Just buy the damn tray from the cooler supplier. We wasted several hours making this to save ounces. Anyway, this shows the steps we did to make the mounting tray, which is taller on the front side than the typical ones. I marked the outline for what I wanted on the cooler in tape and Doug began making the tray mock-up in kraft paper.



    With the template completed it was transferred to CAD, then that was input into our CNC plasma table the we cut out the shape from a .080" thick piece of aluminum sheet, including the slots. Then it was marked and hole sawed for dimple dies then those were pressed in. Now it went into the box and pan brake and 3 of the sides were bent up at 90 degrees. The final side needs to be done on the fab table with a slightly custom backer plate to make that last bend.



    The finished box was now bent to shape, then TIG welded along the edges and the final weight was... 2.1 lbs!



    Then we looked at the Coolshirt 19 qt mount and it was only 2.6 lbs. Really regret not just buying this ahead of time, ugh. Well we got it mounted ans strapped in and realized the pump was dead on the loaner cooler. So we ordered a new one.



    The wiring for the pump needs to be on a 5 amp circuit, which is pretty low. We used DW plugs to make connectors for everything on the lower console "ash tray door" which is now our control panel for the seat heater switch, USB connector, volt meter, and the new suit cooler pump switch. We opted for the simpler on/off switch rather than the speed controller panel you can buy from Coolshirt for $250 (but after using this, I now see why that is used so often!)



    Jump ahead past the SCCA TT at ECR and the new cooler and hose kit arrived, the mounting tray was painted red, and the cooler was attached with the little Velcro straps. This is a slick setup and I will be using this in multiple cars in the future!

    BIG ROUND OF UPDATES!

    After two TT event in a row, and none of our other "real" race car builds even on the schedule for work, it was time to "come into the pits!" and "finish" the C6 work, by fixing last lingering issues I noticed noticed. We had exactly four weeks until the next SCCA Time Trial, which was to be at my home track of Motorsports Ranch Cresson on the 1.7 mile CCW course I have driven on for twenty years. I wanted the C6 to be both fast and reliable there.



    The rest of what we are allowed to do in SCCA Time Trial Tuner 2 class didn't amount to much, so we did almost everything in this round. We tackled several fluid temperature issues with coolers, fixed many fluid leaks that were bugging me, and added a tiny bit of power (and slowed down the power steering pump!) with an aftermarket SFI rated balancer, which is 10% under driven.



    It takes a bit of work to add these additional coolers and meet the Tuner class rules, and those same rules restricted the oil / air separator also. All of this work below was done in the 4 weeks between the SCCA July (ECR 2.7 CW) and August (MSR 1.7 CCW) Time Trial events. Let's dive into each sub-section!

    POWER STEERING FLUID COOLER + PUMP + RESERVOIR

    The hydraulic power steering on this C6 straight out of the 1980s. It has a small reservoir, a tiny cooler (if at all), and starts to overheat quickly - that heat froths the fluid, which saturates the rag we wrap around the cap before each event. The howling pump and constant leaks - a leak AT the pump, one at the Z06 cooler (we had already upgraded to last year) and another at the reservoir - made for the trifecta of leaks!



    I had this novel idea of placing a large high efficiency "plate and fin" cooler under the car - stuck up in the long and skinny spot that the transverse spring used to occupy. This would, in my opinion, get plenty of airflow from under the car without adding to the heat load of stacked heat exchangers up front (radiator + air con condenser + soon to be added engine oil cooler).



    We picked this extremely wide 26" x 4" unit from Setrab, as that fit the strange confines of our transverse leaf spring pocket in the front undertray. We ordered some vibration isolators and Doug built aluminum brackets to fit the cooler and existing subframe holes.



    These brackets mount the bottom of the Setrab cooler flush with the bottom of the car, with the isolators keeping vibrations down at the cooler. The power steering lines were built from Fragola -8 sized (1/2 inch) braided lines (these are all relatively low pressure). The high pressure line is still the stock metal hard line from the pump to the rack, so the pressure worries of changing to a soft line is not there.



    We had debated and researched going to a TurnOne or other aftermarket pump, as the 16 year old OEM power steering pump was leaking at the front seal. We found out that the TurnOne goes to a higher pressure than stock, which we definitely don't need, so we bought a new OEM replacement. The stock pulley is re-used and that all went on without issue.



    We thought that was all of the leaks - not so! The reservoir also had a hairline crack at the molded in seam, shown above left. That replacement was overnighted when it was shown to be leaking, and the new one went on with a fresh rag around the cap. Hoping for 100% leak free at the next TT event!

    THERMOSTATIC TAKE-OFF, OIL COOLER + PLUMBING

    Engine oil temperatures were getting somewhat alarming, with 280-290 deg F and higher temps. This was with rock solid 205-210F coolant temps behind our DeWitt aluminum radiator but NO factory oil cooler in many previous tests and the June + July TT events.



    Another large Setrab (23.5" x 6") cooler was slated to be added for the engine oil cooling, and after looking at several positions the only viable choice was stacked in front of the radiator. Getting the oil out of the engine and back in - in a safe and controlled manner - was the trickiest part of this oil cooler install.



    We started initially with this thermostatic bypass oil filer sandwich plate from Improved Racing. That looked like the best option - on paper - until we installed the 90 deg adapter ends for the -12 AN lines, and that hung down lower than the oil pan. Not safe, time for Plan B!



    This improved Racing oil pan mounted thermostatic bypass unit is much lower profile and the lines come out and can hug the block, and we can keep the stock oil filter or even run a longer one without ground clearance issues.



    Another set of brackets were fabricated by Doug to mount the Setrab in line and in front of the DeWitt, with isolators used at all four mounting points one again. Only slight trimming of the factory radiator shroud plastics was needed, but this will add more heat load to the AC condenser and radiator behind. Due to class rules for SCCA TT Tuning 2 class we could not cut holes in the body to keep from stacking the coolers, and the itty bitty coolers I've seen people try to run behind a fog light hole just aren't going to do it.



    Giant -12 AN sized Fragola braided lines were built to run to and from the oil bypass, which only opens after the oil gets above 185F. We filled the system with Motul 5W50 ester synthetic oil, and the cooler added about a 1/2 liter of capacity.

    ATI 10% UNDERDRIVEN BALANCER + OIL PAN LEAK FIX

    One of my pet peeves is leaks - and the oil pan has been leaking since we bought this car in Spring 2021. Just a drip here, a drip there, but still. With all of the work we had planned I asked Doug to drop the subframe to get the oil pan out. I then took the pan to HPR and ran it through two 15 minute cycles in the sonic cleaner and got it looking like new. There is no baffle kit for this oil pan so we are leaving the pan alone, which went back in with a new GM oil pan gasket, leak fixed.



    Another thing that worried me was the 16 year old stock balancer. I've seen bad things happen with old rubber isolators falling out or slipping and wiping out bearings in an engine. The SCCA TT Tuner rules allow for all different pulleys (except supercharged cars) and ATI made 3 sizes: stock, 10% under driven and 25% underdriven. For a pure race setup the 25% unit would likely be the best but that would compromised things like the alternator, power steering and AC use at idle. And I damn sure use the AC in this car at idle speeds, in the grid!



    After talking with the folks at HPR and our crew I picked the 10% underdriven unit, which should unlock a little power and slow down the power steering pump (which can only help). I ordered the ATI917278 with a 4 rib AC pulley, made for the C6 pulley arrangement. Well...



    The inner hub is supposed to press onto the crank snout with a .002" press fit (meaning: it should be about .002" smaller ID than the crank's OD). Problem was there was an .008" difference. So Doug chucked it up in the engine lathe, cut it to the exact size we needed, and pulled it on with the ATI balancer installer then secured it with a new ARP bolt.



    Last thing I will mention here might save somebody some time. The ATI catalog lists all of their LS balancers, with part breakdowns for the shell, hub, and even has notes for what belts to use. But the AC belt they recommend to work is wrong - what we used was 1.5" shorter (4040395) - and the part numbers for serpentine belts is "smart" - the "395" equates to 39.5", and the "4" at the front is for 4 ribs.

    OIL/AIR SEPARATOR & PLUMBING

    The last piece of this round of updates has to do with adding an air / oil separator. We had noticed after the last TT event that there was engine oil DRIPPING from the cold air, and it covering the bottom of the front of the C6. Oil was also pouring out of the intake due to excessive crank case pressure / high engine revs - I had to actually clean up an oil spill in our paddock spot at the July TT event from this!

    ​​

    In normal use the PCV (positive crankcase valve) system opens a check valve attached to a valve cover when up under engine vacuum, that then allows crankcase pressure to travel via vacuum through a hose that dumps into the air intake tube, and is then burned as part of combustion. That crankcase pressure is both exhaust gases and unburnt fuel that gets past the piston rings, as well as some oil vapor and even water vapor. BUT at higher RPM the crankcase pressure can get a little high and it carries some liquid oil with it (especially the frothy foam that can happen with an LS engine on track) and you get liquid oil pouring into the intake, which causes detonation and in this case, oil dripping out of the aftermarket cold air kit.



    It was so bad we actually pulled the stock LS2 intake manifold and cleaned it and the throttle body out, cleaned out the cold air tube, and also cleaned the front radiator shroud. It was time to act, but we have to keep the emissions system "street legal" for SCCA TT Tuner class, which means the PCV must still function, so we cannot just add a crank case breather / catch can like we do to most race cars...



    For street cars a sealed catch can plumbed in-line with the PCV system is what you want. Above is from my 2011 Mustang GT, which we raced in NASA TT3 class for years but always kept it street legal (for various reasons - not because that class mandated it). We install a JLT oil separator on the car early on, but these came with cheap plastic fittings and hoses that tended to crack or leak, so we re-engineered the whole system with new hoses, hardware, and an actual mounting bracket - not relying on the hoses to hold it. We had to drain this after each event, as it would catch some oil.



    On a race car, like the ST2 classed Mustang above, we tend to go right for a Peterson vented oil catch can. This just has a feed hose (or two) from the valve cover(s) that allows excess crankcase pressure to go into this can, then the oil is "trapped" by the open cell foam filter media inside. The excess vapors then exit via the vented top, and you can drain the oil out after events (like this).



    But for Tuner class, we need a SEALED system that relies on a functional PCV system, as we now have (see above). This is where you keep the PCV (positive crankcase valve) system intact - which opens when up under engine vacuum, then crankcase pressure can escape, and instead of dumping right into the intake tube it travels through a "filter" inside the air / oil separator... then onto the air inlet tube and can be burned via combustion. This keeps stinky exhaust fumes or unburned fuel out of the atmosphere.



    We bought this TFS sealed air/oil separator (above left) but it was made wrong - none of the mounting holes were tapped, and the plumbing looked a little sketch. The only other sealed system we found was this one from Lingenfelter. Their plumbing also looked a bit janky, then Jason recognized the actual tank / filter they were using.



    He found this same exact tank / filter unit online for about $45 and we rounded up some better plumbing bits (without any brass fittings, yuck!) and then I picked a location in the engine bay for it. Then Doug built this bracket to hold it off of the factory battery tray. Yes there are dimple dies!



    The engine bay is getting a bit tight so this spot allows for it to be mounted high and out of the way. Jason spec'd and ordered some black Fragola fittings that Doug then epoxied into the large openings for the crankcase inlet and outlet.



    We ordered some HPS 5/8" diameter heavy duty silicone hose to use for the catch can plumbing - we have had sealed systems that had enough vacuum to collapse weaker hoses. One hose went to the valve cover (PCV) and the other to the cold air intake tube. A third line went from the BOTTOM (drain) of the catch can down through another hose to the 1/2" stainless steel ball valve, shown above right.

    continued below

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  • Fair!
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    There is also a kit from AMT ($350) that is a more complete and better version of an eccentric adjuster - it comes with the six lower adjusters, new lower bolts, and an assortment of shims for the upper arms to use at the alignment shop. And it can get ALL of the camber.



    And they sell an even nicer upper stud kit for $70, too. This AMT kit makes for TEN fixed levels of camber changes and cannot "slip" like the round OEM eccentrics. AMT says this DOES allow all of the slot room to be used on the C5/C6 cradle, too. Even easier - just buy this kit!



    Brad installed the 19x10" wheels and Hankook street tires and I loaded up the C6 and took it to BSP the next morning. We could have driven it there but they need a few hours to do the install and the trip there is 1.5 hours round trip, so I didn't want to have someone follow me each time I went to drop it off or pick it up. We installed the "NB" graphics at this step also!

    ANOTHER BSP ALIGNMENT



    ​​BSP needed about 3 hours to dial in the upper shims, and I had them bias everything to get as much camber as possible - caster be damned! Lots of RED numbers means it MUST be a good alignment.



    The initial settings with our maxed out lower slugs was pretty impressive up front - -3.2 on the LF and -3.85 on the RF. But the rear was holding everything back with only -2.5 deg of camber. They sent me the screenshot above and asked me what to shoot for. I worked with Jason here and we asked them to dial back the front camber (adding shims to the upper arms) to better match the rear camber.



    This was the final compromise, which yielded even -3.3 deg front and -2.4 rear camber. We have the front toe at zero and .28 deg total rear toe in. We'll see how this works, but I will be looking for ways to get more rear camber so we can dial in more front. This battle isn't over!



    Still, this was closer to my "ideal" camber setting and what we had run on other Corvettes, so I had some hope we could find some lap time with this change.

    NEW MOUNT FOR AIM SOLO - MORE RAM MOUNT PARTS!

    I'm still struggling with what video camera to use, and finding a better spot to mount the AiM Solo DL lap timer / data logger. I've had both on suction cups for a while.



    We have upgraded the suction cup mount for the AiM to a RAM 1" ball mount on the PanaVise dash bracket, and that worked well enough - but it wasn't perfect. We could put a RAM quick release 3-axis phone holder onto the 1" ball for street use, but then swapped it to the AiM SOLO mount for track use. Strangely enough I've needed the phone in the car on track more than a few times - sitting in paddock or stuck out on track during a red flag to talk with Amy. Putting the phone into the center console simply COOKS it - literally puts it in "overheat" mode within minutes.



    Secondly, with a simple 6.7" RAM arm and 1" ball mount at both ends angles the AiM unit off axis, and you cannot rotate it enough in the two balls to get it to align perpendicular to the centerline of the car. Its nice that it points towards the driver from the PanaVise, but it makes for skewed lateral g load data. So I bought a bunch more RAM mount arms and ball mounts to see if I could fix both issues...



    And.... this 2 headed hydra is the result. But with the weight of the AiM SOLO and the giant Apple 13 Max Pro XL BBQ phone and holder, its just too much weight for a 1" ball on the PanaVise bracket, and it flops around and is unusable. It was a neat idea but it just didn't pan out. I was hoping to slip the Sony HDR-MV1 camera on a third arm from this junction, but it isn't going to happen. So I will contemplate cutting holes in the silver plastic dash surround to mount two more RAM ball mounts, maybe in the future.



    At track test #11 (above left) I figured out pretty quickly that the multi-headed hydra was not going to work with the phone + AiM, but I still managed to get a "twisted" two piece RAM arm setup to hold the AiM solo "perpendicular" with the chassis centerline. And now the left/right lateral loads finally equal each other. I used that setup again at the July SCCA TT (above right) and that will be the AiM mount for now.

    I will keep using the lackluster dual 1080P Road Keeper camera suction cup mounted to the windshield until I find a way to mount the Sony camera near the windshield (without a suction cup) or find a better narrow angle, vibration resistant, remote mic equipped camera to mount to the harness bar behind me.

    BUILDING A SIM RIG TO LEARN ECR 2.7 CW!

    I felt so lost at the June SCCA TT event at ECR for a number of reasons. I haven't driven at ECR since 2015, on the old 2.5 mile CCW configuration - but from 2008-15 it was my home track and I was there at least once a month. I set several NASA TT class records on the 2.5 but never drove it Clockwise. The extra 5 turns and new configuration for the 2.7 mile track, plus running it backwards, really put me on my back foot.

    ​​

    The next SCCA TT event was scheduled to be 4 weeks after the June event but using the exact same 2.7 CW configuration, and I didn't have time with our build schedule to get the C6 out there - and couldn't find another event that was running the CW config in that time frame, either. So I started asking some Sim Racing buddies for suggestions, ordered a really crappy frame on eBay (don't get this one!), then went to Micro Center, and spent a bunch of money...



    When I found out that some local programmers at #HashtagRacecar worked with the management at ECR and got their GPS scan of the entire track, down to every curb, building, wall and shrub. They created the 2.7 CW and 2.7 CCW tracks for a game called Assetto Corsa, which is on Steam for like $20. I bought a nice PC with a big video card, three 32" curved monitors (2K), and tried two free steering wheels and pedals (thanks Facebook friends).



    The free steering wheels and pedals were all too old so I went back to MicroCenter, bought a Thrustmaster force feedback wheel (TS-XW) and pedal set, a Thrusmaster remote gated shifter, Tony Kannan mouse pad, a good seat of headphones, and a badass TK triple monitor stand. This stand is a HOSS and made a world of difference - and the triple 32" curved monitors are the best part of this rig. I'm into this rig now for "more than I like to admit" but it's looking GOOD.



    There are all sorts of tricks to load custom tracks and cars through a 3rd party program called Content Manager, but with some tech help I got the track loaded and a base C6 car installed (it was terrible). After many hours fiddling with Content Manager, some remote support, I finally got the game to work. Got the beta ECR maps loaded, fired up the 2.7 CW course, and started driving with various original content and modded / aftermarket cars.



    I eventually gave up on finding a car similar to our T2 classed C6 and just drove dozens of laps with a GT3 prepped BMW Z4 using the flappy paddle shifters on this wheel, and not the remote shifter and clutch that I had purchased (there were more tweaks needed to the settings to make those work correctly - and apparently the pedals I have are "total junk" according to the sim snobs!) Just getting dozens of sighting laps helped, as you will see in my July SCCA TT write-up below. Going three seconds faster there after these sim laps was no accident! My wife Amy got in some laps (above left) and now my friends are bugging me to come by and make laps (above right) - and a friend on the #HashtagRacecar discord channel made a custom modded C6 that is pretty close to our car, too! I need to work on my ECR 2.7 CCW course now...

    C6 TRACK TEST #11, MSR-C, JULY 14, 2022 (BUST!)

    I took the 2006 Corvette to MSR Cresson on July 14th, 2022 to test out the latest round of updates - namely the alignment with -3.3 deg front and -2.4 deg rear camber, plus added swaybars from LG Motorsport. I got out there super early and was once again the only car on track in the 7:30 am session. Sadly I was the first car on track since some track repairs on Tuesday...

    ​​

    Unbeknownst to me the track management had dug up and laid down a big patch of asphalt in "Rattlesnake", a series of esses after the Start/Finish. To allow this patch to "cure" they covered this patch in a generous cover of lime dust (this spot has been patched before but kept coming apart). This patch was done Tuesday and I was the first car to drive on the track on Thursday, so it was fresh and powdery. The lime dust was like talcum powder - super slippery, and it took several turns to clear from the tires. It would take days to clear the dust off the track, without any rain or other action by track workers.



    I went out and took 8 laps to try to eek out a little time from last test - I wanted that 1:20.X lap badly but it was not happening on this day with a major compromise to grip. Took another 4 laps in the next session - nope, it was all junk. I worried that maybe these tires had "gone off" but 3 days later we won our class at an SCCA Time Trial - so it wasn't the tires, it was the track issues, Test #11 was a bust.

    SCCA TT @ ECR 2.7 CW - JULY 16 , 2022

    This was to be our SECOND ever Time Trial competition in this narrow body C6, and at the same track as a month earlier! Fearing that the tires had fallen off a cliff (due to the slow times from Track test #11) I was more than a little nervous going to the second SCCA Time Trial at ECR on the 2.7 CW course.



    I had driven many laps on the ECR 2.7 CW simulator in faster sim cars, but would that translate to more lap time here? We had also made the alignment and swaybar change - but had not verified that on track at MSR Cresson yet, so who knows if that would help.
    ​​


    This time Amy and I arrived right at 7 am, quickly unloaded the car at the lower paddock (where trailers have to be parked), and rushed the car up to the upper paddock before all the good spots were taken.



    There is a section up top under a huge mesh fabric shade, and I snagged a spot to setup our paddock. We got too much sun at the June event and being down at the lower paddock we were out in the heat more than I needed to be - now we'd be staged closer to the air conditioned clubhouse and could hang out inside most of the time between sessions, or else in the shade in our paddock spot. This is as close to perfect as you can hope for on a July summer day in Texas.



    I thought I got to the session 1 grid early enough to get a good grid spot (first come / first serve in session 1), but as am still "the new guy" a bunch of people leap-frogged me at grid once again and I started the session in P10. Several cars that ran slower than our C6 last time were ahead so I figured I would be mired in traffic again - and I was. Fought with a few cars for 3 laps and finally got a 2:09.143, which moved me up the grid to P6 - not great, not terrible. At least the folks ahead of me weren't that much slower, but I knew I had several seconds left in the C6...



    The above video shows my best lap in the second TT session. You can see that I held back from Stan's new 2022 GT500 on the out lap by a solid 1/4 mile, building a huge gap that I would then use to put in a 2:06 lap, which ended up being my fastest of the day and 2nd fastest of the entire event. I caught him at the end of lap 2, but my first lap was quickest. Which is sad as that first lap was riddled with mistakes. Lap 2 was much cleaner from a driving perspective, but at 84F ambient and with track temps over 100F, the tires were slowing down considerably (2:07.3) in every lap.



    We stuck around after lunch to try another lap in session 3, when ambient temps were up to 92F. Again, drove better and got it done on Lap 1, but it slowed down further to a 2:07.9. It was only getting hotter so we packed up, loaded the car, and were out of there by 2:30 pm. Fairly confident that we had secured 1st place in T2 again, we skipped the 4th session but watched live timing - nobody up front got any quicker in the higher heat of the 4th sessions.



    I was pretty happy once I saw the results and realized the only quicker car was a C7 ZR1 with AP brakes, good tires, and a member of ECR who is always fast (he was quickest at the June TT event here, too). After a 3 year hiatus I was finally getting better at Time Trial competition again, and couldn't wait to dig into the rule book and see what else we could do to our narrow body C6. The 279F oil temps were concerning, as was my own body temp in a 3 layer fire suit.

    Since that event the C6 was largely unchanged, with only new swaybars and more negative camber, it all came down to the sim racing rig time. With the help of #HashtagRacecar map developer Justin, I was able to drive this track in Assetto Corsa for hours and finally learned the layout. I still have 1-2 seconds of time left just in "driving", but at least I wasn't fumbling around in the 2:09s like in June.



    I still need to work on my "first session gridding" technique, as this has hurt me two events in a row. I don't wanna be "that guy" that claims he drives FLAT OUT and needs to be at the front... but it is becoming obvious that our little LS2 C6 is ending up at or very near the top of the time sheets.



    If you haven't driven at Eagles Canyon Raceway it belies the typical "Texas tracks are all flat!" stereotype with a lot of elevation change, hence the "Canyon name. Really fun track to drive, once you learn where you are going. I am still learning!



    I had a bit of a "moment" in session 1, using a little too much of the inside curbing in Turn 1, based on advice from the track manager. Amy snapped a few pics of the "driftoro" moment there, which was 100% my fault - but it still deserved a meme. Managed to catch that drift and not damage anything other than my pride. Amy was a big help all day, keeping me hydrated, shooting pics, and helping load / unload the trailer. Someday soon SHE will be piloting this in TT and I will be in another car, but not today.

    continued below

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    Project Update for August 30th, 2022: It has only been a handful of weeks between forum thread updates but a lot has happened with our little C6 here and we have some real ground to cover. The C6 now has a little break until the next track outing so it is a good time to catch up.

    ​​

    In this update we will cover a "camber kit" we added along with new swaybars, then another Motorsport alignment, two more track tests (#10 and #11) at Motorsport Ranch, and two more SCCA Time Trials: Spoiler alert: this little C6 now has 3 TT wins in a row! I never could have predicted that last year.



    Before the 3rd TT event in August we did another big round of work: fluid cooler updates and other leak fixes, underdrive pulley, oil/air separator, some brake caliper testing, we bought another set of 18x11" wheels that we thought would fit the narrow body C6, then a new shifter install and tested another seat. Let's go!

    TRACK TEST #10 - JUNE 23, 2022

    I went out to MSR Cresson on a Thursday morning to test the changes we had done in June which included: steeping up to more aggressive G-LOC R16/R12 pads, the long tube headers + Z06 dual 3" exhaust, cold air, and dyno tune (power went from 360 to 382 whp). I was hoping to improve upon Track Test #9's best lap of a 1:21.926.



    I drug along Erik Koenig - engine builder at HPR and a friend of 30+ years. Erik took his first laps in 2+ decades in the C6, after riding along with me. He took 8 laps and had a ball. All testing this time were on the 2 year old Yokohama 315/30R18 A052 tires, as we left the "control" tires at the shop.



    We drove the car over 4 sessions, but I put my fastest laps in the first stint. I managed a 1:21.127 best lap, but it was on lap 7 on boiling hot tires - These A052 tires work best on lap 1 in any kind of heat, but I couldn't get my brain in gear until lap 7. I saw a 1:20.6 predictive lap in there, but couldn't get it done. Saving that for next time!



    The Vmax of 124.9 mph (see above) was a new high for this car, and 4.4 mph quicker than the Vmax at Track test #9 of 120.5 - the extra 22 whp must have helped. I think there is still a bit more power in the tune, as it was ultra conservative with only 20 degrees of total timing advance. I might go back after we add a few more parts and see if we can step on the timing a bit (we only ever use 93 octane in this car).



    Koenig took some pics of me driving in the first session and I analyzed those for quite a while. There is a LOT of visible body roll (see above and in the section below) that we need to address. I can also see positive camber on the outside loaded tires in bog corners.



    The video above is my best lap of the day, that 7th lap in session one. There are still a few nasty driving mistakes in there, but that's just how it happens some times. Not my best driving, but we found 0.8 seconds from test #9 to this #10 test, and there's a solid half second more in it (the 1:20.6 pred kept popping up). I had ZERO cars on track with me in the 1st session, so I have nobody to blame but myself. The temps were warmer than in May and would only continue to climb in July and August - I am thinking about a suit cooler.



    I am still struggling with gearing - the slow Wagon Wheel corner is between 2nd and 3rd gears, and the quick Riccochet corner is between 3rd and 4th. I keep trying those both ways and do not know which is better - but the 2-3 upshift is still a challenge with the stock shifter, and we will need to address that in some way later.

    CAMBER KIT + SWAYBAR INSTALL

    At track test #9 in May we finally had the car aligned and the 18x11/12" Jongbloed wheels and 315/30R19 A052 Yokohama 200TW tires installed, and the C6 broke into the 1:21.X range with a best of 1:21.926 lap, then at test #10 we dropped to the 1:21.1. But the amount of body roll and loss of camber in corners was painfully apparent - this was slowing the car down and wearing the outer shoulders of the tires.

    ​​

    It was time to address both of these issues - with some research, trial and error, and even machining some custom parts before going for another alignment at BSP.

    CHOOSING AND INSTALLING THE SWAYBARS

    There are many swaybar offerings for the C5/C6, and we don't really get attached to a particular brand. We say we are "swaybar agnostic", and I mean it. Sure, if a certain brand has more adjustments, or better endlinks are included, or its a brand we know and have used (and can resell), we tend to go that direction. When it comes to C5/C6 swaybars, we had a few listed on our own website that we can get "wholesale" and resell. The smart move would be to go that route - promote what we sell!



    Sadly the two brands we had access to - pFadt and Hotchkis - are getting really squeezed with supply chain issues. Hotchkis (above) has been in the weeds for 2+ years with some orders taking 6-12 months or longer to fulfill (we have cancelled / refunded virtually of those orders). The Hotchkis front and rear C6 bars were $540 and their endlinks were another $328. The front was 1.25" non-adjustable and the rear was 1.0" dia but at least added some adjustments. And out of stock "indefinitely" when we were looking to upgrade.




    The Puff Daddy stuff is both out of stock and HEINOUSLY expensive - the swaybars and endlinks were $2100 + $500 for the rear pillow ball rear mounts, and all of that was out of stock, too! We have used their parts before (I took the pictures we have on our website) and they are very slick - splined hollow bars with billet aluminum ends, with a 1.50" dia front and 1.25" dia rear and plenty of adjustments at both ends. But at $2600 that is more than 13% of the purchase price of this car. This is a bit of an extravagant option for this car. Hey, if you have the budget, I recommend these, but this is supposed to be a "temporary" build for us. They are really just a hunk of steel tubing that twists - they aren't magic.



    Back in June of 2022 I was at LG Motorsports for a little tuning work and dyno testing (which I showed last time) I went ahead and bought some of their G1 swaybars, both front and rear, and the optional endlinks. The bars were $780 and the endlinks are another $245, for a total of $1025. That's not out of line for hollow bars and adjustable endlinks, and the rear was adjustable (like the Hotchkis). They were also in stock - which our other two options could not meet.



    Our base model C6 had some wimpy little bars, and the 50% larger diameter LG front bar should make for a big improvement in front roll stiffness. It came with new bushings and weighed 15.7 pounds. The stock front bar weighed 8.3 lbs.



    The stock rear swaybar on our base C6 was a tiny little thing at .682" dia and weighing only 3.7 lbs. The LGM adjustable hollow rear bar weighed in at a meaty 8.0 lbs and measured in at 1.070" diameter. The endlinks looked beefy and adjustable. This install would be adding about 12 pounds, but getting the body roll under control should be worth it.



    As with every swaybar install we do, we always measure for "pinky finger effort" to rotate the bar within the mounts. This video explains what we do and it is done to keep the swaybar from being bound up in the mounts. Almost every single aftermarket bar we have ever installed needed to be shimmed, trimmed, or tweaks to allow the bar to freely spin in the mounts - and this front bar needed some shims on the bracket shell to not bind. Brad knocked that out and installed the front bar with some good grease. It is a rubber bushing so we were not able to drill that for a grease zerk in the shells as with the polyurethane bushings that come in most kits. We will keep an eye on that and test for rotation any time the endlinks are off.



    The rear bar was a tick easier - this one rotated freely without needing the mounting shells shimmed or tweaked in any way. That is RARE. Also greased the rubbing bushings and I asked Brad to set the adjustment on full soft out back ad I would tweak it at the track as needed to adjust turn-in (we changed it later to the middle settings).

    ADDING MORE NEGATIVE CAMBER WITH A CAMBER KIT

    Back in May when we did the poly bushing install, using the stock eccentric washers and bolts at the lower control arms we could only get to -2.3 deg front and -1.78 rear camber, with BSP Motorsports cranking them all the way when they aligned it back in May. We had already maxed out the eccentrics (see below right) and paint marked them - and they had not slipped with track use - yet - but it was a worry.



    I can tell you definitely -2.3 / -1/78 deg setting with the stock eccentrics THIS IS NOT ENOUGH CAMBER and it was time to get a proper camber kit on this car to dial in more. And I know the internets like to argue for lower camber settings for every car, especially Corvettes with "superior suspension", but that's all just garbage. This is literally what I do for a living, and we test and race and look at long term tire wear and the data just shows it needs more.



    There are memes we have to point out how ridiculous some folks' camber suggestions are - more than I have room to share here. Yes, even "double A-arm" cars need more than -2 deg of camber when you are tracking with tires making 1.3g - and these Yokohama A052s exceed that. When it comes to C5/C6 Corvettes, the method of getting more camber (what parts to use?) is where my knowledge ran a little thin - until now. Boy did we learn some lessons! We had done research but missed some of the options and skipped some others, and chose this LG Motorsports kit below.

    LGM C5/C6 CAMBER "LOCK OUT" KIT

    The tech around the LGM $369 kit was a little thin, but in June when I was there to have the C6 tuned they showed me how it works on a spare subframe they had on site and said it would "gain about another 1 deg of camber adjustment" which would seem ideal. It is billed as a "lock out" kit, to prevent the camber from slipping - and the mating sawtooth plates make sure of that. But the extra degree of travel just... isn't there.



    This kit is built around part of another bolt-to-stud conversion kit from Vansteel and their own toothed adjusters, that allow for fixed amounts of change. The idea here is to not allow the stock eccentric washer to "slip" under high loads, esp. with a curb jump on track. That never effected our car, but we just couldn't get enough adjustment range - and I had hoped this kit would add more.



    On July 5th we had the C6 in the air for this camber kit install (and the swaybar install) and I helped rummage around until we found the old set of "shims" we had on hand from another C4/C5/C6 alignment years earlier. I wasn't quick enough to spot the offset hole slugs in that "shim" bag, above right...



    Brad got to work and swapped the bolts for the Vansteel studs, shown above. This makes it so the alignment shop can slide shims behind the upper arms to dial out some camber and/or to set caster. That went quickly and looked useful. Now it was time for the saw tooth "lock out" inserts to go in...



    Brad got the first sawtooth plates installed with the bolts in the lower front arms - both of which had a slotted hole in the subframe and are adjustable for camber - and set them to the max outboard / negative camber position. The rear, strangely, only has one adjustable lower bushing - the front lower, as shown above.



    But Brad quickly noticed that this LGM kit doesn't allow more camber adjustment than the stock eccentrics. The first image above shows the extreme "negative" camber travel allowed with their lockout kit inside the unmodified front cradle. The second image shows how much more travel the cradle slot has - its another .100" of movement that their kit cannot achieve.

    THIS ONE GOES TO 11...

    Now .100" of travel might not seem like a lot - but it is. It was worth almost a degree of additional camber travel up front and .7 deg more out back, once we had the car aligned. Read below to learn from our mistakes further.



    The images above show how much travel the lock out kit is giving up - and the top right image is with the bolt pushed to the limit of the factory slot. I'm not saying that this is a "bad kit" because it only allows for the same camber extreme as the stock eccentrics, and it does stop any slipping - so it is a "Lock out" kit. It just doesn't add any more camber than stock, and that doesn't work for me. I wanted this car with max camber, and we'd make something if needed!



    We had to push forward for an alignment appointment the next day, so made our own slugs for that slotted opening. Jason whipped up a simple CNC program and had our CNC crew cut some sluts from .500" thick aluminum plate we had on hand (from camber plates). The rough outlines were CNC machines and then cut out on the band saw - we quickly produced some fixed slugs with offset holes that maxed out the cradle slots. Brad took the rough cut pieces, prettied them up, tweaked each one for maximum camber, and installed them onto the six lower control arm bushing spots (4 of the front locations and the 2 rear).



    Brad got all 6 slugs finished and fitted to each spot on the cradle and wrapped up the camber change, swaybar install, and it all looked great. The problem was... there is already a kit to do this exact thing. And we had it in our shop the whole time.



    So if you want more camber than the lock-out kit can get you, the Puff Daddy 450-401009-A camber / shim kit for the C5/C6 is what you want. And the Vansteel stud kit. The Pfadt kit has offset slugs in various camber locations, so your alignment shop can dial in the camber/caster you want (its time consuming so plan on a slightly more expensive alignment). We had essentially copied their most offset slug, without knowing this kit existed - and was sitting on our bench with the shims in a bag. (facepalm) Oh well, we only lost about 2 hours making the custom slugs. Learn from our mistakes!

    continued below

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    continued from above

    Now it was time to tackle the second Corbeau seat install and harnesses. I had foolishly been driving the car for over 14 months at this point with the stock 3-point belts. The support from these tilt back Corbeaus was better than the stock seats, but harnesses would still help.



    We then dug up the original CAD files for the final bottom mount C6 seat brackets Zach made for the driver's seat, so we could make another set for the passenger seat.



    Initially I asked Doug to install the passenger seat without the slider, and it did sit much lower - but the seat bottom cannot go back far enough at that low height and your knees end up in the dash. That would not work, so the quest for more headroom continues...



    This car still has functional airbags, and I don't want to lose that safety feature. I also don't want to lose the "trigger" sensor in the bottom of the passenger seat, which turns off the passenger side airbags if nobody is sitting in that side. Doug removed this big white plastic sensor pad and slid it under the springs of the Corbeau seat, just like on the OEM seat. That way all of the factory wiring could be connected.



    The anti-sub and lap harness belt anchors were added to the rear bracket, just like the driver's side. And the Safecraft 6-point harnesses were added to the passenger seat - with the sliders - before it went into place.



    We also installed the hybrid 2" / 3" 6-point belts on the driver's side, using the harness bar installed ages ago. Now this would help a driver and passenger stay secured in the seats on track.



    We had ordered the driver's side Corbeau seat with an optional seat heater, but never wired it up. Well since we had the driver's seat out to add the harness anchors, it was a good time to connect that. Doug added the Corbeau 2-position switch to the center console next to the ashtray, which we also modified to add a dual USB + volt meter gauge. The ABS trouble light is next to that. The seat heater now works and Amy is happy - she loves having these in every street car she drives. And with my back, so do I.



    The seats are now both installed with the Safecraft harnesses and a functional seat heater. While these seats fit my butt and torso very well, I am lacking in headroom that just cannot be gained without sliding the seat further back. The slider has the travel but shape of the back of these Corbeau seats limits that additional rearward travel to the interior panels and console, so I am stuck driving the car with the seat back tilted excessively to gain the headroom - which is less than ideal. But again, this was supposed to be a car for Amy to drive, so I just grin and bear it.



    As another nod to safety I wanted to add a 3 pound Safecraft Halon style fire extinguisher to the C6. This is not the same Safecraft company as the belts (although it used to be). This is an extremely well made part, with the handle and trigger assembly CNC machined from billet aluminum. Light years better than the cheapie Kiddie fire bottles I see in so many track cars, which often have plastic or stamped sheet handles and triggers. These Safecraft bottles can be refilled if you ever discharge them, and should be more reliable and have more volume to discharge than the cheaper Halon 2 lb bottles.



    I asked Jason to design a small bracket that bolt to the factory passenger seat front studs. This .090" thick aluminum bracket was made to hold a with a Drake Offroad fire bottle quick disconnect mount. We then strap the bottle to the removable portion of the Drake mount, and it comes out with a simple pull of the red anodized handle marked "PULL".



    We have put similar hand held fire bottles in dozens of cars in this same spot, even race cars with full fire systems. As we would see at this next TT event, sometimes you have a driving or car issue and have to pull off into the grass. There the hot exhaust can light off dry grass quickly. A little $250 or so investment in a 3 lb bottle like this, on a sturdy quick release mount, can save a car from going up in a small grass fire, or help put out a friend's car who is on fire. As always, let the track crew get to the scene of any fire and GET OUT of your car when it is on fire. But if its a small flare up, something like this can save you from a bigger fire. Hopefully I will never have to use it.



    Last but not least is this CAGS bypass - that is a janky system GM used from the mid 1990s on for their 6-speed Tremec manual transmissions, which allowed the computer to force you from 1st gear to 4th gear on a low throttle upshift. Instead of grabbing 2nd gear you ended up in 4th, and it SUCKS. These "skip shift delete" kits were all the rage back in the day and I bought this a year ago, then finally found it and had Doug install it in this round of work.



    The stock plug was a little melty, so when he went to put the bypass in I had him wrap the whole harness in DEI header wrap, then secure that away from the exhaust.

    AMB TRANSPONDER MOUNTING, CLEAN UP, & ADD DECALS

    The last things we needed to run an actual Time Trial were an AMB transponder + some class letters and numbers. But first, I did a full wash and detail on the exterior and engine bay...



    After I got the brake dust and grime off the exterior and cleaned under the hood, I brought the C6 into the shop and Brad waxed the paint before the decals went on.



    I won't get into it here, but I had started the quest for some class number/letter decals and Vorshlag logo stickers nearly a month sooner. Two previous suppliers both dropped the ball so I had to ask Doug to make these with his new CNC plotter he has at his place. There was a little miscommunication on the size of the number boards, so the "92" on the doors is big enough to see from space.



    The transfer film that I had in storage for 5 years was badly aged, and I gave that to Doug to use. Brad and I tried to install the 2 layer number boards wet but had to call in the professional - Amy. She has patience I just do not possess, and over the next 24 hours of placement and drying she got them to lay down.



    I took the car to get gas and the decals stayed on - success! We had the more than the minimum required "numbers and letters on both sides" with the addition of a front and back set, too. And some small Vorshlag logo decals.



    Last but not least is the AMB transponder, which needed to be mounted "within 18" of the ground with no metal underneath". We found these MyLaps brackets from a random supplier for much less than most places, but I had to buy 4 to get a good price. They will come in handy for this battery style AMB transponder I have (my other is a wired unit). These stay charged for about 3 days so I needed to be able to mount this in a spot that was easy to access, but also without metal in the way of the transmitter. The left rear storage cubby under the rear glass worked perfectly - easy to get and only plastic underneath. Now its time to load up and go compete!

    SCCA TT @ ECR 2.7 CW - JUNE 18, 2022

    My experience with ECR goes back to when it first opened in 2008, and I ran there monthly through 2015 and still occasionally through 2018. I used to call this track home, and have 1000 laps here... "I used to rule these streets!" The thing is, I only ever ran the 2.5 mile course, and only ever ran it CCW. Well since 2018 this track changed hands and the new owner "started from scratch"... and changed the layout considerably.



    Now the track is 2.7 miles long, with turns added from T6 though T9 and they changed T10 a lot. They also changed the curbing and run offs to allow the track to be run backwards - and that is what this June and the July SCCA TT events were running: the 2.7 mile course CW. I have ZERO laps on this layout and NONE in this direction. It might as well be an all new track for me. This is why we had the Hankook tires mounted for the first session - I fueled heavy and planned to run the entire session on these hard tires, to try to learn this new-to-me layout.

    I was signed up for Time Trial, and the Texas Region SCCA had TT broken up into 2 groups. The faster folks were in the Red group and I was with the slower folks in Green. I took this as a bit of a snub and worried that I wouldn't ever get a traffic free lap, but the opposite was the case. This was the best thing that happened to me all day. With the big 2.7 mile course and a moderate number of entrants in my session, once I cleared a few folks that jumped ahead of me on grid in the first session, and was gridded by times for proceeding sessions, I had nothing but traffic free sessions all day.



    Amy and Erik joined me for this Time Trial event, and I am glad because I really needed the help. This was a hot Texas summer one-day event and I got pretty dehydrated through the day. I was super nervous, not having run a Time Trial since August 2019, almost 3 years in the past. Almost nobody at this event knew me, as there had been a lot of "new member churn" during the Pandemic. A lot of the old racers haven't come back, so it is a lot of new faces.



    When I got to grid for the first session, nobody knew that I set multiple track records on the old 2.5 mile layout, and when I asked the grid worker to put me at the front, she asked what I have run here... I said well, I used to run 1:55s on the old 2.5 course, but I don't know the 2.7 and I never ran it backwards. She moved me to P1 anyway, yet two other "regulars" jumped ahead of me on grid. Again, nobody knows who I am anymore, and heck... I could be slow AF...



    And on the Hankooks I did feel VERY slow and only managed a 2:14 lap on my 7th hot lap, after I got around the two cars that jumped me on grid on the first lap. The tires just didn't make much grip in this coolest session of the day, but I needed to be out there the entire time to learn this track, and I got nearly 25 minutes of track time to learn. It wasn't nearly enough.



    For the next session I had to swap to the A052 set, which should be 2-4 seconds faster. I wore my fire suit all day and was really sweating profusely, but Amy helped me change tires and we got the set swapped in under 8 minutes. Then made it to grid and parked in P1, due to having the fastest lap time in the Green TT run group by number of seconds.



    Leading the group out I made sure to "bunch up the pack" so that I wouldn't catch the back of the field, then went "green" by Turn 3A on the out lap. This put me in clear sailing for lap 1, when I laid down a 2:09.542 before seeing a small grass fire and subsequent red flag 3/4 of the way through my 2nd hot lap, which was showing a 2:08 predicted time. We sat out there for 5 minutes while the track crew came out and put the grass fire out (the car had driven away safely after the smoldering started), then they brought us into the hot pits... after sitting idling for 10 minutes I was boiling inside the car and had to run the AC for a bit.



    Then we went back out for 4 laps, but the tires were too hot to do better than a 2:11. That 2:09.5 was good enough for the class win but I was NOT happy, so I stuck around for after lunch - when it was 96 freagin degrees by then - to run session 3.



    That session, starting at the front, on the A052s, and without a fire and red flag, allowed me to make a string of laps - still learning this course. My AiM showed a first lap of 2:11 (missing a 2-3 upshift), then a 2:10, then I did a cool down lap, then finally made a a hot lap 4 of a 2:09.19. The AMD loop showed a 2:09.396, and that was enough for the class win that day and 8th quickest overall for the event. I wasn't exactly thrilled but after a 3 year hiatus and being so lost I was happy. I was also massively dehydrated and I don't remember much after that...



    The oil pressure CAN data stream was not in the video, due to a mistake in the video / gauge template I used - trust me, its not an issue. The video itself, well, I am hesitant to show this in-car video because my driving is so bad. I make numerous driving mistakes and never found the right braking points or apexes on a number of blind corners. I was so damned lost that I promptly went back to the shop and built a driving simulator just to learn this track for the following month - which made a HUGE improvement. But the next TT here had a lot more cars in T2 class, and some were a LOT faster.

    WHAT'S NEXT?

    I had planned to cover work after this June 16th TT event - we had Track Test #10 (with a new personal best for the C6!), a big change to the alignment, Track test #11 (a dud - the track was under construction and my laps were SLOW), we added new swaybars, the sim rig build and learning ECR, then another SCCA TT at ECR where we went faster on the same course.



    I will coverall of that and more next time, but needless to say the C6 is getting much faster, easier to drive, and there are still things we can do in SCCA Tuner class that should improve things even more. I've got a few small tweaks left for power and will have the car re-dynoed soon to see if those changes help, too. Tune in next time for more crazy antics in our narrow body C6, #ProjectNewBalance!

    Thanks for reading,

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    continued from above



    The two stints in the first session were all pretty cautious, listening for tire rub, feeling out the brakes, tweaking pressures. I a 1:22.759 but way out on my 4th lap of that 1B stint. The tire height was shorter than the 19" Hankooks and this required me to alter my shift points and made 2nd gear pretty much useless.



    Stint 2A saw a 1:22.7 then a 1:22.3, then I came in the hot pits to alter tire pressures and let them cool off a tick. I went back out in 2B and ripped off a 1:21.9 and a 1:22.0 on the first 2 laps in the video linked above. I was still feeling out using 2nd gear in Rattlesnake vs 3rd, and it was pretty much a wash.



    Lateral grip levels of 1.3g were much higher than before on the Hankooks (1.15g), but braking loads were still stuck at 1.15g (and still are to this day). I was happy with the 1:21.926 lap and saw a 1:21.7 predictive. I was also happy to have a track day without any "incidents". Braking still not exceeding 1.15g but lateral was 1.30/1.37g, so we're definitely needing more aggressive pads and/or better calipers. G-LOC R16s are inbound, so we'll try that next before throwing bigger money and/or time at a "Big Brake Kit" solution (the "cheap" front AP upgrade is $2500 nowadays).



    Jon showed up with the Mustang after my second stint and we got him all signed in and ready. I took him for a ride along in stint 3A in the C6, then did some "lead follow" laps in stint 3B (which is why the times were slower). I then rode along with Jon in the Mustang using my helmet-to-helmet comms trying to get him acquainted with the track. We broke for lunch around 11:30 and I was loaded up and out of there by 12:30, but Jon and Dan stayed out for most of the day taking laps.



    Dan was able to snap some pics of the C6 in corners, and these two show me that we need MORE NEGATIVE CAMBER and there is a LOT OF BODY ROLL. So some sort of camber kit is needed, as are aftermarket swaybars. Jason and I began researching options for these future upgrades later that day, back at the shop.

    The brake cooling improvements were significant - after removing the "ZR1 lip" and un-blocking the brake inlets (and opening up the "nozzle" inside the wheel well), the front rotor temps to came from 750 F (at the last track test) down to 505 F (shown at the end of the in-car video above), which is huge; rears were stable at 400-450F. Just still not enough braking force on the friction circle to my liking. I am used to braking much later in corners in my old 2018 Mustang GT, which was 3900 pounds with driver (600 more than this C6) but it had Ford ABS and a big brake kit (it would make 1.3-1.4g stops). Still, it was nice getting into the 1:21.9 lap time range, but I felt like these tires should produce more lap time drop than that. Was hoping that with more camber and better brake pads we could see another one second drop on these same A052 street tires.

    ABS PLASTIC FRONT LIP (FAIL)

    After removing the carbon lip I began looking for an option that was both legal for SCCA Tuner class and that did not block the brake vents. There are SO MANY options out there and most of them for the narrow body actually do what this carbon lip did - they have the brake inlets set at the wrong width. I searched high and low and found a somewhat affordable ABS plastic lip (legal for Tuner) that looked like it was actually made to fit the narrow body C6.



    This did indeed have right style inlets built into the lip that lined up with the brake inlets - that was a plus.



    We did a quick mock-up on June 1st and it looks like it might fit? The side air deflectors once again have to come off to fit this up properly, which Doug tackled that day before diving into the header install shown below.



    When the exhaust work was wrapping up a week later it was time to mount the ABS plastic lip for good. Now it was obvious that this part was a giant hunk of crap. While the brake inlet ducts did line up, the floppy plastic piece didn't fit the contours of the front end at all. After fighting with this for an hour and seeing that it was never going to fit properly, I threw this thing straight into the dumpster where it belongs. DO NOT BUY THIS JUNK. Just not worth the hassle.

    PADS, ROTORS & A FRONT HUB

    The 1.15g stopping data didn't impress me at Test #9 with the Yokohamas so I figured now that we had the ABS and brake cooling a bit under control it was time for a more aggressive pad.



    We had ordered these R16 fronts and R12 rears, which was a single step up in track compound aggressiveness from the pads we had been running. And never wasting an opportunity for product pictures I shot these sets in our studio and put them on the website in place of the "generic" pad pictures we had for the C5/C6 PBR caliper pads.



    The R12 fronts had seem some real abuse over 8 track days, and the drilled rotors were wearing these very quickly. The rears looked pretty good after 5 track days, due to the fact that the front brakes usually do 80% of the stopping work + some brake bias issues.



    This C-Tek branded active hub had started to fail after one track test, and we had ordered this X-tracker SKF for that - now it was finally installed. Aaaand the speed sensor was bad. So now instead of just checking Ohms for a new speed sensor before we push in the long wheel studs and it is installed, now we hook up the Matco scanner, plug in the speed sensor, and turn the hub before we put them on. Sheesh...



    So another SKF was ordered under warranty and that went on along with "smooth" rotors. No more cross drilled holes! We had to search around and pay extra to NOT get the dang cross-drilled holes in the fronts, but we found some from Centric. Of course I weighed them, and this should slow down some front pad wear. The rear rotors were left alone - the rear pad wear was already too good to worry about that.



    Doug got the smooth front rotors installed, the second SKF bearing put in worked, and the front and rear G-LOC pads. The system was bled with fresh RBF600 Motul fluid and the brakes were ready for the next track test.

    HEADERS / EXHAUST / COLD AIR / THERMOSTAT

    This round of exhaust work happened later than I had hoped, with as much time we lost with the factory ABS issues, then the weird part failures at multiple track tests, but it was now time for more power.



    I always like buying high quality, American made, properly designed, and well fitting stainless exhaust headers - usually from American Racing Headers, which we are a dealer for. I have purchased their 1-7/8" primary / dual 3" exhaust with a catted X-pipe systems for my 2011 and 2018 Mustangs, and they both fit great and picked up a big bump in power. Doug here at Vorshlag had a set of used stainless headers that came off of his C6 Z06, with the X-pipe, so I figured... well, they fit his car, and they were 1/10th the price?



    Again, not what I would normally recommend or use, but we had a narrow window of time when the car was on the lift doing the brake pad / rotor work above, and Doug sold me these headers for almost free. I don't even know what brand these are, and I figured if they fit poorly or the performance wasn't there, I would punt and get the ARH versions - as there shouldn't be a lot of time and money invested.



    The factory log style exhaust manifolds were pretty bad looking, so my prediction of seeing 25-35 whp peak and 30-50 whp mid-range power boost with long tube headers should hold true here (that did not happen).



    These random import headers did fit the LS2 C6 well, surprisingly. They aren't pretty, but again, for this car they should work well enough.



    Well the first thing that didn't fit was the X-pipe and mufflers, which were factory dual 3" for the Z06 / LS7 engine and dual 2.5" pipes on the LS2 engine. My mistake for not knowing that the LS2 came with smaller stuff. Looks like an excuse to upgrade the mufflers!



    Doug found a pair of used C6 Z06 mufflers and pipes on Facebook marketplace for a few hundred bucks. These OEM mufflers have vacuum controlled "active bypass" valves that default to open, which is how we installed them initially. We will go back later and scavenge the factory Z06 vacuum canister & plastic tubing from my 2007 Z6 in the barn then put these on a switch to be able to quiet the mufflers down for street use.



    The pair of stock LS2 mufflers were 10.4 pounds lighter than the Z06 mufflers, so we wiped out all of the weight drop gain from the manifolds to headers. Again, not what I had planned for this car, but these were available the same day and we didn't lose any time within this narrow window we had open on the lift.



    The next thing that didn't fit, once the 3" LS7 mufflers were installed, was a missing piece of the X-pipe exhaust kit. Doug seemed to have lost these rear pipes, so I had him fabricate this 2 foot long section with mandrel bent stainless to join the headers and X-pipe to the LS7 exhaust. And add V-band clamps to that junction. Nearly two days of fab and welding later, and yea... I should have bought a new set from ARH. It costs money being cheap!



    Back in 2021 I searched the entire internet for an aftermarket cold air kit to fit the short run 2005-07 LS2 C6 Corvette. Did not exist. There were plenty of options for the 2008-2013 LS3 Corvettes, so I bought this SLP C6 LS3 cold air inlet + filter kit - hoping it would fit this LS2 car. It did, and has more airflow potential than the stock airbox, but it did take some trickery to make it work. We had to switch from the LS2 style MAF sensor to an LS3 style MAF, but I will talk about that in the next section.



    The filter and tube all fit, but the front mounts for the filter mounting bracket that was included for the LS3 car was off, so Doug redrilled those holes and added rivnuts to fit the LS2 car.



    These rivnuts then helped these rubber nipple mounts that fit into the SLP air filter. As an experiment prompted by Erik Koenig at HPR, we pulled the stock 205F thermostat and installed a 180F. That lowered the coolant temps to 201F in the car, down from 210F.



    The old spark plugs came out (they looked fine) and were replaced with NGK BR7 plugs. We also added BBK O2 sensor harness extenders, which is common for long tube headers.



    I'm a little embarrassed that I didn't splurge for new headers, but overall the finished result was nice. The exhaust all tucks up into the tunnel and has the same ground clearance as stock. I don't love the ball-and-socket collector flanges, but I didn't want to invest the time to replace those with V-bands on a cheap set of used headers.

    CUSTOM DYNO TUNE (LGM) + WIRING FIXES



    On June 7th the folks at LG Motorsports had scheduled a slot to dyno tune our C6. The goals were simple: to fix the tune to work with the new exhaust + LS3 style MAF swap and get us a conservative "road race safe" tune. That is very different than a "drag race" tune, or a simple "street tune". When you spend 20-30 minutes at wide open throttle, the tuning needs change drastically over drag or street tunes.



    The owner at LGM is Sergio, who is a well known tuner for HP Tuners, AEM and Motec systems. He was going to use HP Tuners to clean up the EFI tune on this C6 to make the LS3 MAF work (we did the wiring adapter - just needed some programming changes), and give us a 93 octane safe road race tune. They work on Corvettes almost exclusively and they are only 15 miles from my shop. I unloaded the car on the 9th and let them do their thing.



    Two days later the car was ready, and was running great. I was disappointed with the gains, however, as it made 360 whp SAE bone stock, on True Street Motorsports' 248 series DynoJet chassis dyno. To only gain 22.5 whp with a cold air, long tube headers, a full 3" exhaust and a custom tune seemed down, but Sergio explained that his DynoJet 248 series dyno tends to read lower than others. Or was it the cheap headers we installed? Or not enough timing? I was second guessing everything at this point...



    Sergio had done a good bit of street / driveability tuning as well as dyno tuning. He said there was some tuning funkiness that only showed up in 2nd gear pulls on the street; with enough acceleration something was losing contact. After shaking and wiggling harnesses it turned out to be the LS2-to-LS3 MAF adapter harness from Casper Electronics that I purchased. He had this connector zip-tied together to keep the contacts together for the remainder of his tuning, but once back at Vorshlag it was easy to see. Doug got to work repairing this.



    We ended up buying a new connector for one end and Doug re-pinned all of the wires to make sure they were inserted fully. That fixed the issue and it hasn't cropped up since. I still think we are missing horsepower somewhere - I don't know where, but I'm going to keep looking.

    BRAKE COOLING "SCOOPS", 2ND SEAT, FIRE BOTTLE, SEAT HEATER & CAGS BYPASS

    This round of work happened right after the dyno tuning and just before the June 18th SCCA Time Trial. I had missed the NASA TT event the week before due to scheduling slip, but I don't think this car would have done well in NASA TT3 (it is several seconds off the pace with no Hoosiers for that series). Instead we would concentrate on the SCCA TT event prep, and hope that I don't get trounced...



    The flat round opening in the lower plastic panels that feed the brake cooling duct were pretty sad. They only worked due to having the air dam wall behind these openings, but those really make it hard to run the straps to the front wheels every time I trailer this car (30+ times and counting!) I had envisioned these mini-inlet scoops in a dream, but we had made something similar on my C4 Corvette and they worked great. Jason and I spit balled some ideas then I worked with Doug on the template in cardboard, that he then turned to aluminum sheet and formed int he roller.



    The overall size was minimized from the initial prototype and these barely stick down below the flat undertray, and above the bottom of the air dam section - so no loss of ground clearance. I was hoping for longer stints to be possible, as the SCCA TT at ECR coming up was on a course direction and layout I had never done - so I would need to run the entire 30 minute front session on the R-S4s to learn them.

    continued below

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