Vorshlag S550 & S650 Mustang Development + 2018 GT, 2024 Darkhorse & #Trigger

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Vorshlag S550 & S650 Mustang Development Thread + 3 Shop Cars - October 23rd, 2014: This thread is where we talk about our testing, shop work, parts development, and racing with S550 Mustangs (and later S650 Mustangs). We will use this thread to share weights, pictures, and tech of various S550 Mustang parts and cars we work on. I started this thread in 2014 when this chassis was just arriving, and in February 2018 our shop bought a 2018 Mustang GT, which we are now using for more hands-on testing. We will use this shop car for development instead of just relying on outside testers' cars, and I have re-written this intro to reflect the change in direction for this thread.



This forum thread was started in 2014 just on our little forum, but when I revived it in 2018 we cross-posted it to some other forums we sponsor (or that allow us to post there), after we bought our red 2018 GT. Getting this car after the '18 major sheet metal facelift and new Direct Injected 5.0L engine made it seem more relevant now, and I'm glad we waited. Automotive forums are declining, but we feel these are much better places to share data and a better long-term repository for tech than social media (where everything posted is wiped out in about 48 hours), so that's why we go to the effort. We will be updating this thread on the following forums:

• Vorshlag Forums - we own this one
• Track Mustangs Online - sponsored; lots of Mustang track junkies
• S197Forums - sponsored; lots of autocross and track junkies
• Track Junkies - They tolerate us; cross-make/model track junkies

We will try to answer every question in this thread on all forums we have cross-posted on, so feel free to ask or comment about anything you see. Please keep your comments to S550 related things that "we would know" (we are not a basic repair shop, body shop, EFI tuner, or stereo/bling shop - we specialize in suspension, wheels/tires, brakes, safety gear, aero, and chassis work). You can always call or email us at Vorshlag, too.


Autocrossing and tracking this car on the skinny stock 235mm all season tires was hilarious!

We did both a track test and autocross (above) in the first week of ownership, in bone stock form, and it was pretty terrible. The next week we upgrade the base model GT with 11" wide wheels/tires, aftermarket monotube adjustable coilovers, plus our front camber/caster plates and spherical Rear Shock Mounts.


That's more like how a Mustang should look...! 19x11" Forgestars and 305 Bridgestones

As always, any picture you see can be clicked for higher resolution versions. Videos are almost always linked to our YouTube channel, for best results there. As you might know we weigh everything - and that is what prompted the start of this thread in October 2018, when we started weighing these S550 cars.



Stay tuned as we add more S550 content to this thread, from work we have done over the last 4 years as well as new development we tackle using our shop 2018 GT and other testers' and customers' cars.

FIRST REAL WEIGHTS OF 2015 MUSTANGS IN 2014

At long last an S550 Performance Pack 6-speed GT finally arrived in Dallas. Not the one we ordered, but a stocking order GT with similar performance equipment. This one has power leather seats (not the leather Recarcos) with Sat Nav, 12 speaker stereo, the bigger 15" 6-piston brakes, the 19x9/19x9.5" wheels, the works. All the goodies, probably the heaviest way to get an S550 other than convertible automatic GT (yuck!)



You have all seen the "magazine" weights thrown around, and like usual, the numbers are bunk. I swear these writers don't know how to work a set of scales. We see this every time a new model comes out - either they weigh a car with a full tank of fuel, or two people inside, or lead weights in the trunk, or just parrot the marketing materials they were given. Can they just plain dyno and weigh a car for us gearheads, PLEASE??



Corey White of Five Star Ford of Plano gave me a heads up that their very first 2015 Mustang had arrived earlier today. It was the FIRST GT 5.0 Performance Package car he knows of in Dallas, as there was a production delay on these cars due to some changes to the placement of the catalysts.


This 2013 GT is caged and has all the W2W safety gear. With one seat it is almost 3300 even

After finishing up with a customer's delivery of his race-prepped 2013 GT (built for NASA ST3, see above on the scales) we loaded up our brand new wireless Intercomp digital scales and rushed over to Five Star Ford to get that pony weighed. Why? Because I'm always a skeptic about almost ALL data on cars, and only believe what I can measure on real scales, first hand.



Turns out this thing is about 100 pounds lighter than all of the numbers the magazines had been throwing around. 3718 pounds with low fuel - low fuel levels are easier to compare between cars and is often how we race these cars in Autocross or Time Trial (depending on fuel tank/pick-up). This weight is with the "Trunk Junk" (TM) removed, which includes the floor mats, trunk mat, and the emergency tire inflation kit (no optional spare tire).



Trunk junk came to 13 pounds, and there's likely another 15-20 pounds in the trunk mounted sub-woofer. It is removable but they asked me NOT to take it out, since this car is their very first 2015 and going right on the showroom today. After we weighed the car, Corey White (the salesman in the pics, and a real gear head) told me to hop in and we drove to their fuel pumps to put a splash of 93 in the tank. Then he hopped out and said, "You're driving!" How could I say no?



We went on about a 15 minute test drive, re-striping the streets of Plano in Pirelli rubber. The car drives REALLY well, rides very similarly to a CTS-V... good compression damping, firm but supple ride on the choppy concrete roads, and hauls ass when you give it the Go pedal. Motor feels strong for a zero mile car with similar acceleration to the 2011-14 GT or Boss 302. The PP cars all have the 3.73 gears and Torsen axle. The sticker price is shown below.


As always you can click any picture for a larger rez version

The ergonomics are spot on. I've sat in a couple of these but driving it was amazing. 6'7" Corey fits in here well, and my 6'3" frame was swallowed up with ease as well. The shifter feels GREAT and the lever is right where my arm wanted it. The steering wheel has a big FAT rim and gauges that were easy to read. The seats were good, but the Recaros are better - that option worth the extra coin, if you never plan on installing real racing seats.



Loved the switch gear, and the materials + leathers were top notch. Pedal spacing was perfect for heel-toe downshifts. Just a quick street drive but I really liked it.


Left: 2014 Camaro Z/28 with A/C and 3/4 tank, sans trunk junk = 3835 lbs. Right: 2011 GT Brembo Premium 6-spd, sans trunk junk = 3563 lbs

Closing thoughts: this car will be a hot seller. We happened to weigh a 2014 Camaro Z/28 today (equipped with A/C, see above) and it was 3835 pounds with 3/4 tank of fuel. So the S550 is considerably lighter, which is good news. I was pretty upset after hearing the (bogus) 3850+ pound numbers being thrown all over the internet for the S550, and had essentially given up on these cars before they even arrived. That was probably a bit rash, and now I am back on the Pro-S550 bandwagon.


Since we introduced them in 2014, our S550 camber/caster plates have been a huge seller

Look for products for this chassis coming from Vorshlag soon - and don't worry, we're going to keep supporting the S197 Mustang even after our 2011 GT is sold (edit: it was sold in 2015). The dyno numbers for the S550 look promising, and the exhaust gains seem pretty big for simple work. The wheel/tire packages on these cars are SUPER heavy - we have a Forgestar CF5 18x10 that fits this car, plus 18x11" wheels in the works, and there's even more "extra weight" in the exhaust and wheels. We will try to get some weight out where we can...

Thanks for reading,

[Fair!]

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Brad had all of the steel surfaces cleaned up and the twin disc setup went back together properly, and then the transmission went back in. Then the driveshaft, exhaust, etc. A lot of hours burned chasing this issue.



I never felt any tire rub at the NASA event on the first time out on the new wide Hoosiers, but both front 335mm tires were rubbing just barely at the lower spring perch. This left some weird wear saw tooth pattern right at the shoulders of the sidewall to tread. A small 3mm spacer was added up front and they never touched again. The fenders had a LOT of room up front to allow for this, we just kept it inboard too much.



The rear tire that had the belt issues is shown in the pictures above - I've seen this in REALLY OLD sets of Hoosiers, and ones like this that were "stickers" and unused but just stored for years. And that pair of 345/35R18 A7s were 9 years old. Even stored indoors, that is too long, so I had to spend $1200 for a new pair of rear tires...



I do hoard tires, and it hurt me to throw away "one-event old" tires (even if they were 9 years old), then had the new 345s were mounted. Hey, its just money!



After the clutch job was wrapped up the engine was fired up and was now throwing a new fault - "ABS Failure". We swapped out the M-2353-CA Ford Racing ABS unit with a spare we had in the shop and that was not the issue. After some additional testing one of the 4 speed sensor wiring channels was throwing the fault.



Brad re-wired that wheel speed sensor channel and that fixed the glitch. The brake lines were bled and the car was finally reset and ready for yet another back-to-back race weekend.

APEX LAP ATTACK MSR 3.1 - APRIL 13, 2024

This event's timing was too soon after these other events above, and we should really be doing more testing with so many issues cropping up. I just feel obligated to go to the Apex events because we are sponsoring the trophies for this series in 2024 (and again in 2025). The car was reset at Vorshlag after the NASA ECR event, which itself went pretty poorly, and this time I was ready to stay all day and shoot for FTD with Apex. Amy was out of town so I was there running solo (left house at 5 am, got home at 9 pm). I was hoping for a 2:11 lap time on this big 3.1 mile4 track, as I had run a 2:15 on street tires the previous October.



This 3.1 mile MSR course with about 27 turns is one I've run several times before - not my favorite, but I wasn't a noobie here. This Apex group is FAST, though. I started P1 in the first session and went out and ran a 2:14, but I wasn't leaving the yellow LA1 classed C7 shown next to me in grid above. Timing and scoring was down for session 1 so nothing counted, so I went out P1 again in the 2nd session (after they fixed the timing loop).



There is a nasty pair of transitions from the traditional MSR 1.7 to their 1.3 course on both sides, where the two courses are joined to make the 3.1 mile course. I had left the splitter pulled up a bit in anticipation of this bum[p sets of transitions, and it was indeed a BIG issue. I had to slow down a LOT at both transitions to keep from crashing the splitter over these very bumpy track portions. I remembered why I hate running a high aero car on this 3.1 course.



In the 2nd session I ran a 2:13.6 but Ahmer, my main competitor, ran a 2:13.1, and that was the last good session: 69F and mild winds. I went out again and pushed HARD in session 3, but the wind had really picked up, and it was warmer, and all I could managed was the 2:13.3 lap shown above. Most folks slowed down. I went out again in session 4, and ran a 2:13.8. I ran again in session 5 and had a 2:14 at 3:30 pm, but the times just wasn't there. Wasn't traffic, wasn't the car, I just didn't have it in me that day. Lots of laps taken, but I think that I missed the golden times session 2 - I would do no better than 2nd place.



This was a windy day and I still fought the transmission shifting issues - it wasn't the clutch. I tried wider shoes and then nearly drove off track pressing the gas and brake at the same time. My head-to-head battle against Ahmer in LA1 class was brutal, and he got me this time by 2 tenths, a well earned victory. I was pretty frustrated with my times, but 2nd in class was still 2nd quickest of the event. They don't have 2024 results posted, so you have to take my word for it.



I tried running without the Traction Control (still dialing that in) but that was a nightmare. Part throttle response was pretty nasty, and I worked with Billy at Rapscallion during the day between sessions, who was there pulling data. Felt like that the clutch fix wasn't the right answer and I suspected we had now worn the 3rd and 4th gear synchros too much. We have another T56 Magnum XL in the shop from Amy's widebody FRS, so we will look at that when we have time.

SCCA TT, ECR 1.65, APRIL 28, 2024

We had very little to do to the car after the Apex event, and that gave us a 2 week break until this SCCA TT event at ECR on the 1.65 mile CCW course. And the SCCA events mattered more, as they have a regional TT championship I was chasing on street tires, with the small aero. I had only driven this 1.65 mile short ECR course one other time in 2023, but it is pretty short and sweet.



We had both the '24 Darkhorse (T2 class, which Amy won) and Trigger (in a huge Max1 class) at this event. The weather was a mess on this day and started off wet in session 1, semi-dry in session 2, dry in session 3, and dry turning to wet in session 4. I ran every single session trying to get a quick time, and adjusted the traction control to try to keep the rear tires from spinning. TC was finally working well after tweaks by Billy at the Apex event 2 weeks prior.



I fought all day against a big Max1 class (7 entrants) and pushed through all 4 sessions, setting a best of 1:11.43 to win it in the last session. I couldn't top Mike Dusold's Unlimited 1 classed 1400 hp Pikes Peak Camaro's time, but we got close (within .5 sec).



As you can see in the in-car video above, I was still fighting pedal spacing / 3 pedal downshift techniques. This car's transmission seriously fought me for 2 years, and after a few too many botched downshifts I had wrecked the synchros in 3rd and 4th. It started raining pretty good on my cool down lap, so that first hot lap was really crucial to get the class win in this final session.



Data logging showed some decent numbers, with 1.5g lateral and nearly the same forces in braking. Looking at the video now I can remember how touchy the downshifting was, and it was holding back lap times. We later got an auto-rev matched downshift feature added, which really helps - when it works.



This was the last time we would compete in this car on the Apex forged 18x12" wheels. The offset is not right for the wider fenders, and in the later events we ran 18x13" wheels for 200TW events. We also noticed some extreme wear on the front rotors - I noticed cracks in both front rotor rings when loading up - which I will cover below. But a win is a win.

EXTREME ROTOR WEAR

These rotor rings made it 6 track days before they "popped" and this began a series of short lived rotors and investigations. We also noted some uneven pad wear, inside and outside pads, on the front calipers. We eventually traced this down to a foundry and metallurgy change that we don't have a great solution for even now in 2025. The company who used to supply our brake kits is now focused on off road trucks and Dakar rally, and not big, heavy, time attack Mustangs.



We swapped in new rotor rings before the next event, and a bit of brake fluid, but otherwise the car wasn't touched. This set of rotors only lasted 6 events, which we can easily track based on the timestamped images of work on the car and events we enter.



This was the length this new batch of rotors lasted - 6 events. Which was baffling, as the previous sets lasted 3 seasons.

WHAT'S NEXT?

I was going to keep going but that first 4 months of 2024 was intense with a LOT of events and shop work on this car, and I've already filled up 5 entries hitting the 20K character limit (about 20K words). Trigger started getting better and better in the summer of 2024, with big wins at the next two Apex Lap Attack events and new personal bests set at our main "home tracks" MSR 1.7 CCW and ECR 2.7 CCW. I'll cover that next time.



I also had a dismal showing at LS Fest Texas, and found a whole bunch of other things to fix. It was a season of racing, finding issues, then spending time and money upgrade & repair them, and keep testing - all with the push for SCCA TT Nationals in September.

More next time!

Terry @ Vorshlag

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At the March 30th event I drove VERY poorly and had a high speed off track excursion, so Brad had to replace two of the Professional Awesome carbon splitter strut rods. They were frayed from the impact but they still held on in later sessions that day!



The next weekend we had scheduled to enter a NASA Time Trial event with the new Hoosiers and the bigger 12" splitter, so Brad made the taller air dam for this splitter version at this point.

CLEARANCING FOR REAR FLARES

One of the things that people associate with Vorshlag is putting BIG TIRES on everything, and that is a fair association. We have added giant tires and flares to SO MANY CARS that I have lost count. And it goes way back to my early days of track and autocrossing in the 1990s...



Always make sure the car owner is OK with the work involved, because this is a one way trip. There is NO GOING BACK once you add flares because you have to hack up the bodywork to make the wider tires fit underneath the flares. In 2013 we added flares my wife's 2011 Mustang (above left) and she was NOT on board, and I got into some trouble. No means no!



The front fenders on this body swap was easy, as it was a complete replacement carbon fender. But out back of this unibody chassis, we had to chop up the rear fenders and the underlying inner fender structure to clear the 345mm Hoosiers. The addition of the over-fender itself was cake compared to the clearance work underneath. We usually quote 12-15 hours to do this correctly on a steel unibody car for the rear. Brad used painters tape to make an arc and started cutting the outer skin with a reciprocating air body saw.



Once you are through the outer fender skin it is time to cut the layers of structure underneath away until you have the "bump travel" tire clearance you need. Brad switched to a our little Milwaukee M12 saw at this point. NOTE: There is all manner of foam and insulation inside the outer skin that is very flammable. Remember to have a buddy there with a serious water gun handy to put out small flare-ups when you start welding!



With the steel outer skin and inner structure cut away, it is time to check bump clearance. We mounted up one of the new Jongbloed 18x13.5" wheels with a 345/35R18 Hoosier and removed a rear spring, then raised that corner up until it runs out of shock travel OR the tire bottoms out on the flat horizontal surface of the inner fender structure. What we don't want is the sharp "point" of the outer fender curving down to dig into tread, as that can cut a tire. We keep cutting that structure out until the tire touches flat sections.



At this point we have the clearance we need but some serious gaps to fill between the now cylindrical inner fender structure and the outer skin, which has been raised several inches along its wheel arch. We need to close up this gap and restore structure to the unibody with steel sheet panels. Brad starts here with some cardboard to make a template for our filler panel.



At this point you transfer your template to some 18 to 20 gauge steel sheet. That's when Brad used the English wheel to add a bit of arc to the piece. That was then placed over the gap (with all mating surfaces sanded clean of paint) and a 2 man job of tack welding and holding is done. Brad was using a big hammer to hold the panel in place while Austin tack welded that to the outer skin.

Again WATCH OUT FOR FIRE. It might be wise to have a third person watching for flare ups with your water sprayer loaded and ready to put them out. If you see smoke under your welding hood it is far too late. Ask me how I know (yes, our crew caught part of the left rear fender on fire, but put it out quickly - with the nasty, powdery chemical extinguisher that made a MESS. The burned paint was repaired, and is thankfully all underneath the over fender)



The filler panels for the rear fenders were made in two parts and we used a skip weld tacking technique to keep from adding too much heat to the surrounding sheet metal. We let the panel hang past the fender so we can get a nice shelf there for easier welds on the top side.



Anything you can do to avoid overhead welding is always good. But you'll have to do some of that on the inner seams, which overlap the inner fender structure. Once you are happy with the coverage of the welds you can grind off the outer "shelf" that overhung the fenders. Brad used a flap disc on a 4" angle grinder here.



Post-Weld seam sealer was slathered onto all of the welded seams. After that dried the area was hit with self-etching metal primer, to prevent rust down the road. This is an important step that so many skip.



Now the actual flares could be fitted. This took another 8 hours to trim, mark, drill, rivnut, and fit together. After mocking up the fender we picked a spacing for the many holes we had to drill for exposed mounting bolts. This might not fit the car show crowd, but for racers who run into things, it makes for a quicker repair. Brad installed dozens of M6 rivnuts into the chassis.



The Anderson JTP kit includes 3 pieces per side for the rear, and the rear section shown above left bolts to the main over-fender portion. Then there is another lower section that ties into that and the rocker. The secondary sections were test fit with the main fender in place, then the holes to attach them together were marked, drilled, and thru-bolts and nuts were used.



We test fit the rear wheel and tire again and checked for clearance - and that fat 345mm tire was starting to eat into the added lip that these over-fenders had built into the outer edge. That's nice for structure, but we gotta let these tires eat. So that was marked on the carbon fiber fender and Brad trimmed that away to allow the tire to clear in the upward "bump" direction.



Once the lower portions were fitted they look seamless. Brad had to open up the oval hole for the fuel door to allow enough clearance for the door to open and close, but otherwise these fenders fit REALLY well. The glossy carbon finish is striking and the weight of these parts was a rounding error.

ADDING HOOSIERS + WEIGHT CHECK

Now it was time to mount the other 3 Hoosier tires - for the two fronts and the other rears. I put the 315mm Yokohama next to the 345mm Hoosier below for reference. Not even close...



This weight check on April 4th was the second time we put the Mustang on the scales since the roll cage was added. We had a full tank of fuel and the numbers were bleak - 3604 pounds, without driver!



We still had full interior to run SCCA Max1 class but the big tires and big splitter we wanted for NASA and Apex events. The wheels were very light but adding the 175 pounds of roll cage did us no favors.



With some extra wood ramps we were able to get this car loaded into the trailer on Friday the 5th before a NASA event on the 6th at ECR. We had our big splitter, big tires, and the full cage since our last NASA event. Let's see how it stacks up...?

NASA AT ECR, APRIL 6, 2024

This was a super frustrating day. Amy and I got a crappy parking spot because most NASA weekend entrants show up Thursday or Friday. We're just here for the day so we got what we got. At least we had Annual Tech for the log book from the March event, so I parked up near the front for the first session.



Well nobody parked ahead of me on grid, so I led out the first run group, the TT Warmup. Which went very poorly for me! Apparently there was some leftover fire retardant powder buried down inside the left rear fender (the one that caught on fire slightly, in the section above), and at speed that turned into a dust storm inside the car. I mean the interior was spotless when I got there.



The dust was SO THICK that I thought the car was on fire, but the smell was wrong. I came in quickly in that warm up session, never got a lap, but after checking everything I went back out again in HPDE 4 session and even an HPDE 1 session - just to make enough laps to blow all of this powder out of the cabin. What a mess!



I went out in TT session 2 and started at the back, because I had no official lap time. I set a huge gap to the field on the out lap and ran a 1:58.5 lap, which I felt was junk. I mean hell, I'd run a 1:59 on street tires here the year before, WTF?



It came down to several issues, but we finally traced the total lack of rear grip to the two 9 year old "sticker" rear 345mm tires that I won with Hoosier contingency way back in 2015. They just never switched on, and one rear tire's carcass started separating belts and was VERY MUCH not round in the 3rd TT session, which I had to abort. That pair of tires went right into the trash pile after this event.



I was actually pretty embarrassed by my performance, even with a new Personal Best at this track and in this car. I should have purchased new rear tires, but money was tight and I had these "new" sticker 345mm tires that I could not make myself throw away.



I felt slow and was holding up cars 2 classes down, but somehow I still won TT1 (which had some of my SCCA TT buddies) by 8 seconds. I took a bunch of short laps but was stalled out in traffic for most of the day and just had the ONE sub-2 minute lap. I had to clean up and shower at this event and head to a friends birthday party, so it was a long day.



I just rewatched my one quick lap from this event, and it isn't great - I was fighting issues with the clutch or transmission all day, a situation that is only getting worse. Back end is sliding all over the place. I was by no means proud of that win, and I was really chasing the faster TTU cars above me - I knew at this point we have a lot of work to do.

RESET, REPAIR, REPLACE - CLUTCH DISCS, TIRES AND ABS FAULT

The season was in full swing now and we had one week until the next Apex Lap Attack event at MSR. After the Mustang was unloaded it was time to get ALL of the fire retardant dust out of the car - Brad masked up and took the M18 Milwaukee air blower to the interior outside the shop. THAT got our the dust, followed by some serious vacuuming and wipe downs of all surfaces.



The clutch we have in this car at this point is a used ClutchMasters 850 series (8.5" diameter) twin disc that a customer wanted a refund on after driving it for 2 days on the street. I don't actually love this clutch, but it was an expensive unit that fit this transmission. To try to fix the shifting issues we ordered new discs as a last attempt to save this expensive clutch system.



Pulling the Tremec Magnum XL takes a bit of work - exhaust, driveshaft, shifter, clutch hydraulics, etc. Not a fun job but clutches do become wear items with 620 whp engines.



We were grasping at straws once the clutch and pressure plate was removed. The aluminum flywheel has a steel facing for the 8.5" diameter clutch face, and it had some hot spots. We had started with a hybrid organic / bronze disc stack and were moving to a straight bronze clutch setup with the new discs.



The wear material looked fine, just some hot spots. But it was out, so the new sintered bronze "race" clutch pack was installed. Hey, it is a $1800 clutch kit and I don't want to just toss it if this new set of discs fixes it.



The measurement for the free play from the hydraulic TOB to the pressure plate was checked and it was off, so an over-night delivery of the shims was ordered and that was re-shimmed to the ClutchMasters specifications by Brad (none of this work or parts fixed the shifting issues, sadly).

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After cutting the opening, and making a template in cardboard, Brad then made a curved vent panel from textured ABS plastic sheet. That was bolted to the fender, and a lower aluminum panel / bracket seals off the bottom plane, and helps the ABS hold its shape. There was also a missing fender liner that was replaced, and both liners were cut and formed to feed these fender vents in a smooth manner. Not F1 level good, but pretty good for a nasty little Time Attack Mustang.



These wider carbon fiber lower skirts from Anderson are about two inches wider than stock, and that can help out under the car, so it was time to install these. The factory skirt mounts with crappy plastic push pins, so Brad drilled out those holes and added massive M8 rivet nut threaded inserts.



Of course these skirts don't even remotely line up to those holes, so he then drilled a new set of holes and riveted the damn things on at the right spot. They otherwise fit nicely and nest into pockets of the fenders at the front and rear nicely.



This carbon hood from Anderson was purchased in 2018 and used on my red 2018 GT for 2 seasons. We took that off when we sold the car and it has been on Trigger since 2020. Now it was finally time to cut on it - to open up the "GT500" style hood vents considerably. Brad, Jason, and I once again met and agreed upon a series of slats to remove - that would later mate up to a radiator exhaust vent hood we would make much later in 2024. Always smart to be planning ahead when you are chopping up expensive carbon fiber bodywork!



The pic above shows the GT500 style carbon hood 3 pairs of slats removed, so a lot more air should be able to exit naturally. Now to goose that airflow - adding a Gurney flap.



This is just a piece of aluminum bent on the sheet metal brake at a ~30 degree angle, then using our shrinker / stretcher it got a bend laterally along the centerline of the hood - matching the shape of the hood openings. That was riveted in place, masked, and painted semi-gloss black (pro tip : paint it before you rivet it on!) This little lip should enhance airflow out from under the hood, hopefully reducing lift as well.



One thing we temporarily tested was reinstalling the factory cowl panel. We did this on the 2018 GT when we ran this hood at higher speed events like COTA and it reduced the back of the hood lifting up several inches at speed. And above right you can see a new panel Brad added to our single air filter box, which is force fed from an opening in the grill. This now closes off the airbox and seals to the hood - that should keep the cold air fed into this box from bleeding out to the underhood area. He also cut a slot in the panel for the hood prop, making it easier to stow properly.



There is a massive hole in the back corner of the front fender wells on the S550 - in all models. We made a set of these "close off panels" from that ABS plastic sheet again, cut to shape and formed a bit with a heat cut. The green "laser" shows the cut line for the template, which was applied to the ABS version that bolts in place. This should keep air from bleeding out of the front fender area and going under the car, which could potentially disturb airflow from the splitter and cause lift.



A new ride height setup was added to raise the rear ride height 0.5", then lowering the front .25", adding .75" more rake to the car. The front splitter was dropped at the leading edge to a 1.0 deg down angle. (NOTE: this later led to problems with the air dam, explained below)



The starter issue from the March event led me to simply buy a new starter from a better brand (AC Delco, which is what we use on customer builds), replacing the cheapo brand from RockAuto we used before. Hey, it was 2020, and everyone was broke! This starter was then installed with some DEI reflective heat wrap, to keep header heat from cooking the solenoid again (it has since worked flawlessly for the last year - again, parts brands do matter).



Finally we had Billy the tuner remotely log into the Haltech to change the trigger temperatures for the fan to kick on and off. As you can see in the video above, we did some extended run testing afterwards and now the fan kicks on with coolant temps of 200G and turns off again at 195F. This worked fine on a cool late March day, but as we found out at LS Fest, it was still insufficient for long periods of idling in very hot weather. The thin Mishimoto 16" diameter fan simply did not have enough airflow for hot day idling, as we would later learn. (And also - the rear steam vent port leak, which was impossible to see)

TRACK TEST #6 - MSR - MARCH 23, 2024

I hauled out to MSR on a member day to test ALLLL of the changes above, as well as to dial in the new traction control. We always would rather test big changes in private before showing our ass at a competition event with new parts. I was hoping to see the car - still on fresh A052s - get back closer to those 1:14.6 lap times I ran in October of 2023. We got to the track and it was SUPER windy, which is not the best conditions to test a car with lots of aero, but I was hopeful and went out in two sessions for 25 minutes of driving trying to find the time....



I was making laps but the car was fighting me, and the aero changes did not make the time drops I had hoped for. After my first session with a couple of attempted hot laps, I checked over the car and noticed that a major "flutter" I felt above 125 mph was the splitter opening up a gap above the air dam! The dam thing was too short.



The lap times were.... the same as at the lousy NASA event 3 weeks earlier, almost to the tenth of a second. Ugh. I could reproduce this lap time over and over, but nothing more. Traction control was still not operating as planned and after several tweaks I was fed up with that. But this gap above the air dam was more of a concern at the moment. I screwed up, didn't leave an overlap of the airdam to take up for changes to the angle, and that opened up a gap that nullified all of the front downforce.



After two test sessions and many lap attempts with no improvement, and the wind just was not dying down, I called it. So Amy and I we loaded up the car and sat inside the trailer and sheltered in place while a bit of a storm blew through, which you can see in the video linked in the image below.



I should have checked the forecast before wasting a day coming out here, but we had an SCCA TT event in a week and learning that the air dam was too short was something we needed to know, so that could be remade in time. Frustrating second day at the track in this car for 2024, but we still learned something.

TALLER AIR DAM AND OTHER REPAIRS

After the test day shown above Trigger didn't need much, but the air dam clearly wasn't tall enough. Air was indeed getting over the top and causing lift, so I asked Brad to re-make the air dam but 1" taller. Brad had to swap out the 12" splitter for the SCCA Max legal 6" splitter for the next event, too.



That taller air dam was made fairly quickly with more ABS plastic sheet (he also later made a taller one for the 12" splitter we use for NASA and Apex), and the new overlap of the OEM lower splitter lip is clearly shown in the images above. This will give us the ability to raise or lower the front lip of the splitter, changing the angle of attack, and still keep air from going above the splitter. This extended air dam is pretty common and something I should have spotted before the last test. My mistake.



The Mustang was then cleaned up and readied for another SCCA Time Trial the next weekend, with the 200TW tires mounted to the little 18x12" wheels and stock rear bodywork for one last time...

SCCA TT, MSR 1.7 CW, MARCH 30, 2024

We took both the 2024 Darkhorse and Trigger to this SCCA points event, but I will save the DH updates for a separate post. We're just going to focus on Trigger in this write-up. We were running the same MSR 1.7 course but backwards, going clockwise. And while it is the same length I've never matched my CCW times here in any vehicle going back 20+ years.



I won Max1 class that day by a good bit, but not as much as we should have. My fastest lap was in the first TT session, a 1:17.6 lap (fully 3 sec slower than my Oct 2023 1.7 CCW time) My competitor Stan got faster throughout the day and ran a 1:19.0 at the end of the day, so pretty close for a street car GT500. Dusold was there in his Pikes Peak twin turbo Camaro, and I was ahead of his times in the first 2 sessions, but he got some issues worked out and 1:15.0 at the end of the day.



The issues with Trigger were numerous, and all within me - I had a migraine for 24 hours and I couldn't hold down food or even think straight. I never felt like I put a good lap in, and the clutch and synchros were giving me fits, with the clutch not disengaging all the way making both up- and down-shifting difficult.



Immediately after this event we ordered the Tilton ST-246 clutch that I should have installed long ago. Once again, brands matter - and Tilton is in the top tier of clutch brands for a reason. Painful expense, and I still to this day cannot make myself throw out the ClutchMasters twin disc setup (so much money).



I ran that 1:17.6 lap on lap 3 of the first session, and it was straight garbage. I kept pushing all day and ran all 4 sessions, but had a nasty off in the 3rd session that damaged the splitter and splitter rods. Pushing, pushing, pushing to just get nothing. I ran the 4th session anyway, and saw a predicted time that was faster but was blocked on the last corner - I felt like the car should have been in the 1:15 or 1:16s. It was a windy, windy day which is never good for aero cars - but this car has run 1:14.7 on the same course backwards here on street tires before! Being 3 seconds off this car's Personal Best was super frustrating.



Honestly I was once again leaving with a win, but embarrassed. I didn't even compile the data with the video, as it just wasn't worth watching. I was hoping that in the near future with the Tilton fewer shifting errors, and a wider track width with the new 18x13" front wheels for 200TW tires that the car would be magically faster...

REPAIRS, CARBON REAR FENDERS INSTALLED AND JONGBLOED WHEELS ARRIVE

At this point I was committed to the carbon widebody kit and had ordered two different sets of wider wheels to replace the 18x12" Apex wheels we used with the Type-ST front fenders and nose we had on the car earlier (see below). The first set to arrive (and second set ordered) was an 18x12.5" front and 18x13.5" rear Jongbloed racing 3-piece set.



I was on this delusional kick that the Big Hoosier Magic of 2012-15 that we experienced on our 2011 Mustang would unlock huge amounts of time. It did unlock 1.5 seconds at MSR Cresson, which ain't nothing, but it wasn't the 2-3 second gain we had hoped for. I suppose some of that is just how good the 315mm Yokohama A052 200 treadwear tire really is?



These 3-piece wheels are very light, but the wheel mounting holes were incorrect - they came at 1/2" diameter (worked up through S197) but did not fit over the larger M14 studs used on the S550 and newer Mustangs. Not what we wanted to be doing before test fitting the wheels, but we drilled them out larger with an M14 bit. Then recut the conical seats with a special 60 deg chamfer bit we ordered. I wouldn't be upset but we did spec out the M14 lug hole diameters on the Purchase Order.



With that out of the way we could start test fitting these ultra wide wheels on the rear with the Anderson JTP rear over-fenders in place. These add a LOT of tire and wheel room out back, so it was time to mount some fat Hoosier A7 tires to these wheels.



Above left you can see the 18x13.5" wheel bolted up with the stock rear fenders, and they stick out over 2 inches. The front already had the Anderson flared carbon fenders on, and the new 18x12.5" front wheel clears easily. I took some old 345/35R18 Hoosier A7 tires I won back in 2015 (?!) that were still "new sticker tires" and had them mounted up. Wait, 9 year old tires? They were "free" and never mounted, so what could go wrong? (that proved to be a really bad idea) We mounted these up April 2nd, 2024 and it was time to order new 335/30R18 A7 fronts.

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Two quick videos above - these are right off my phone, no editing, nothing fancy. The first one above left shows the cage as it was prepped right before paint. The second one at right shows the painted cage and these powder coated interior panels in place before the rear Lexan and seats were reinstalled. Just click on the images, as always.



The rear wing uprights in black look SO much better, and Brad put all of the dash bits back in place. For the moment we had no glove box door, and I was worried that this would make the car not legal for SCCA Max classing. We also ditched the A-pillar plastics and carpet, but after asking the SCCA rules board they pointed out that Level 3 Safety regulations made all of that unnecessary. We could even remove the side door panels, door glass, carpets, center console and headliner with the addition of the full cage.



Because I am a masochist, I also ordered a window net mounting kit and a custom window net from Stroud Safety. Our crew welded on the brackets and the net fits the opening perfectly, as it was made to our template from the car. I haven't used the dang thing once, as I feel that nets are more of a hindrance to exiting a car quickly than the small benefits they bring in driver containment. And I am not W2W racing so I don't have to use it.



The video linked above shows a wider version of the "big" 12 inch extension splitter, which we built for use with NASA, Apex and SLB rules. But after measuring our trailer we realized that loading the car would be a nightmare with this, and decided to chop that extra width off instead of using the extra width those series allow. We also show in this video how we redesigned the splitters mounting holes to allow the same set of 4 splitter struts to work on this bigger splitter and the tiny baby 6" SCCA legal splitter, which makes life much easier when swapping before a race.



One of the rear quarter windows (2.5 pounds each) had to come out to access part of the cage and weld a junction of tubes - just the right side shown above. Instead of paying some windshield company $200 to come out and bond that glass back in, I asked Brad to just install the Lexan quarter window that we had bought in 2023 from Plastics4Performance. It was class legal for SCCA and didn't make much of difference in weight (3/4 pound lighter). Since we didn't have the big wheels and Hoosiers yet, I installed fresh letters and kept the same class lineup: M1 for SCCA, TT1 for NASA, and LA1 for Apex.



We weighed the car on Leap Day, Feb 29, 2024 - and it definitely gained some weight. We knew what the cage kit weighed, and we used the whole dang thing. Sadly we removed almost nothing as we added the cage, so it was nearing 3500 pounds with nearly a full tank but without driver. Oof.



On March 1st it was time to load up the car, with a fresh set of sticker A052s mounted to the forged Apex 18x12's - which looked comically small with the wider front carbon fenders. Again, we didn't have the time to cut the rear fenders and install those over-fenders, so for this one event we had carbon from the doors forward but still sported the factory steel rear fenders. Loaded up and ready to test the next day at MSR Cresson, which was a NASA TT...

NASA TT - MSR-C - MARCH 2, 2024

Due to so many unknowns, I only signed up to run for Saturday, as I wasn't chasing points or trophies with this series this year - especially on street tires. This was just a test to see if the car was ready for Super Lap Battle a week later (it clearly was NOT). When the 3-piece wheels arrive and we had fresh Hoosier A7s mounted, then I could take this NASA series more seriously. I knew what the car ran here on the 1.7 CCW course in October of '23 (1:14.6) and December (1:15.1) on these same tires and same basic aero package. Power wasn't touched, either.



Amy and I were sick from the night before, so it was a rough wake up call at 4:45 am and rolling out with the trailer at 5:30 am. Arrived at the track at 7 am, unloaded, got the car annual teched, then off to the TT meeting. Went on track at 8:45 and I started up front thinking I'd be fastest - Ha! That was optimistic.



First session was a total mess with aborted laps by everyone after some dumb kid in a Rush that was in another group accidentally came out on track right in front of me on our first hot lap. Aborted that lap while they were black flagged furiously, then I ran a crappy 1:16.828 lap. Yikes, so took another cool down, and ran the same time within .01 sec on another attempt. I was scrubbing in a new sticker set of 315mm A052s, getting them ready for SLB the next week. Came in, scaled at 3750 lbs, fully 650 pounds heavier than our declared TT1 weight. Yeesh, the extra weight from the cage and other additions was adding up! This was a TT2 car on street tires, once you do the NASA calcs.



The car was pushing, and not making the front grip it made in December on the same basic setup. Second session I went out P2 behind a TT3 car, and on the out lap I let him build a gap, but not enough. I caught him going into the fastest corner (Big Bend) and was following too closely - I guess the wash from his aero threw off the front grip even more, and I had 2 wheels off at 90 mph - cooked my lap and ruined the session. Couldn't get quicker than a 1:18 and they mistakenly gave me a 4 wheel off and DSQ. That meant I had to do another session, as the "warm up" first session times don't count, and I had a DSQ in session 2.



Billy the tuner had loaded a tune for the traction control, but it was not working at all, and even with just 620 whp it was hard to drive out of corners on these 200TW tires. I managed a 1:16.6 in the third session of the day, but the car felt terrible - lacking front grip, and shock changes didn't help. I went to impound after that session, and waited in line to be weighed. After sitting idling for two minutes I noticed the coolant temps start to rise, and at 220F I shut off the engine. As the line pulled up to scales minutes later, I went to crank the the engine and nothing happened. Click.



Ended up pushing the car across scales and aborting the last TT session. Just disgusted with the car at this point, with such a terrible start to the season, especially after a six week THRASH to get so much work done. I wish this setup would have been done a week earlier and I could have tested privately at a member day, but we only finished the car prep the day before.

With our only technician leaving for vacation Monday I had nobody working in the shop the next week (we were still down a tech), so I aborted my SLB entry due to the poor showing here and lack of ability to fix anything. Being two full seconds off this car's previous best on the same tires at the same track!? Not worth the $1800 entry fee and embarrassment from what would be a poor showing at COTA.



Got a tow over to Rapscallion Motorsports and after cooling down a bit, and a quick whack with a hammer, we got the starter to work - but it was clearly running hot. Later we would find that the little Mishimoto fan was not up to the task of idling this engine for more than 1-2 minutes. And much later we found a leaking steam vent line at the back of the engine, so it never built pressure. Left the car at Rapscallion for some more tuning work to try to get the new Traction Control working and we loaded up the Darkhorse to take back to the shop.

AERO TWEAKS AND OTHER REPAIRS

A week after leaving Trigger at RMS they had the traction control working now, so I picked it up March 9th. Just a quick 5 hour round trip, but with issues leftover from the last TT event, this wasn't the time to do another track test and it was a super windy day.



After Brad was back from vacation March 11th, we got the Mustang back into the shop and Jason, Brad, and I looked at what had changed that could explain the 2 second loss of lap time at our main test track - and the loss of front grip. I was complaining about lack of front downforce, and some of the photographs that I paid for showed some front end lift. There was a lot of work tackled on this car once again over the next 2 weeks, so I'll try to cover it quickly but completely.



We made a plan to lower the front lip and change the angle of the splitter, close up a GIANT pair of holes that the 2018 front bumper cover left, add some front fender vents, replace a missing fender liner and extend that to cover some openings, install the wider carbon Anderson lower side skirts, and add a Gurney flap to the vented hood. Lots of little things that hopefully add up to some gains.



The first fix was this somewhat ugly plastic cover for these lower openings - I mentioned that you could walk a large rabbit through these openings, so the new Race Roll patches covered up these holes. I didn't like how these looked, and we ended up making these in metal later in 2024, but they were fully functional.



Another potential big source of front lift is air trapped under the front fenders, being fed from the massive splitter tunnels that aim air at this area (and through the brakes). We taped out a cut area after conferring with lead engineer Jason and Brad got to work cutting the brand new carbon fenders (ahh!) There was also some questions for the SCCA TT Board about max body width that I sent in (see above left pic).

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Project TRIGGER Update for July 16, 2025: The 7 months since the last update in this thread (the first half of the 2025 season) with Trigger have been pretty a prolonged nightmare. But in this entry I will instead cover the first third of the 2024 season, which had its ups and downs, but some good results. We eventually made huge strides with this car in safety, aerodynamics, tire fitment, traction control, power, and other systems.



The early part of 2024 saw the Mustang get the full widebody carbon fiber Anderson fenders front and rear, which let us put massive 335mm front and 345mm rear Hoosier A7s on, plus a giant splitter for events like NASA and Apex where we could run these DOT R-compounds (above). We continued with 200TW tires for the SCCA Time Trial series (below), but still had our share of struggles the whole season.



This early third of 2024 we at least left the functional Haltech 2500 EFI and MSD intake + 103mm Throttle Body setup alone, still making 620 whp - without the need for spending or craziness. I wish we would have left that engine setup alone, as it worked pretty well after the traction control was dialed in. But as you've seen in this build, we're always pushing for MORE! Even when that has a tendency to add hassles, costs, and failures. Learn from my mistakes?

BIG PLANS, RULES CHANGES AND MORE POWER = HOOSIERS NEEDED?

We run in three different Time Attack series in Texas: SCCA, NASA, and Apex Lap Attack. In 2023 making 620 whp, this car was able to just stay inside the TT1 class (and do pretty well) in NASA with 200TW tires, and we won Texas Region's SCCA Max1 class in 2023 on 200TW tires that year as well.



A rules change announcement in early 2024 for the Apex Lap Attack series (which felt 100% aimed at our car) made Trigger stuck in the top class (LA1) even with 200TW tires. We felt like this car should not have been competing with Prototypes, boosted V8s, and tube frame race cars on Michelin slicks and sequential transmissions. But with more power planned for the 454" engine later in 2024, Trigger was stuck in LA1 class, and for NASA might even be pushed to TTU class. At this point adding Hoosiers would help for those 2 series.



It had been a good decade since I had run the big 335/345mm Hoosier A7s on my TT3 classed 2011 Mustang (above left), and to fit these monster tires we needed wider bodywork. And while we eventually installed the full Anderson Composites carbon JTP widebody kit (above right) on our S550 here, we still stuck with 200TW tires for SCCA TT Max1 class, which remained our primary series & class to build and compete in for 2024.



But building for two wildly different sets of classes and very different rules led to a lot of additional spending - we now needed to reinforce both splitters (small for SCCA/LS Fest + bigger for NASA/Apex/SLB), and then wider wheels for both the Hoosiers as well as for the 200TW tires (to better fit the wider bodywork). Not only were we adding LS Fest (200TW) to the 2024 schedule, we wanted to add Super Lap Battle at COTA (hoped to run Limited class on 200TW). This led to a lot of spending, a 6 week thrash of prep, and also a number of compromises. Advice: be careful what you wish for, and try not to run in every possible class in one car.

TRIGGER GETS CAGE + WIDEBODY = AN INSANE 6 WEEKS OF WORK!

The roll cage was a safety upgrade we needed to make for a while, as the carbon doors we added in 2023 do not have any crash protection. We only had a 4-point roll bar (behind the driver) and I was rolling the dice with my safety. With a plan to enter SCCA TT Nationals at NCM, a track surrounded by concrete walls, a roll cage was beyond required.



After research we ordered this Trackspec motorsports roll cage kit, which arrived on February 5, 2024. As if this wasn't a big enough job, we also decided to do the carbon widebody conversion, which arrived a week earlier - meaning, we needed to tackle both a cage build and a major bodywork swap at the same time. This was poor timing, but plans from the "winter off season" (which is about 2 weeks in early January) led to this convergence of projects.



Super Lap Battle was creeping up March 8-10, 2024, but I had hope that we could tackle both of these big projects AND add new wheels and a bigger splitter, do some testing, and make that event. We were not even remotely close to making that impossible deadline, as these projects snowballed and other delays set up back. We did test with the new aero and 200TW tires at a March 2nd NASA TT event, but the car was 2 seconds off its previous pace, so we scrubbed SLB for that year.

TRACKSPEC CAGE INSTALL

This actually went fairly well and was wrapped up in barely 2 weeks of shop time, from removing the glass and dash, installing and welding in the cage, painting the bare metal, and putting it all back together again. That was because we used a cage kit from TrackSpec Motorsports - pre-cut, pre-bent, marked and ready to weld in. It really went in fast!

• Using a cage kit vs a Scratch built roll cage: LINK

Instead of writing this section twice, I encourage you to go to the forum section linked above where we cover many steps of this TrackSpec cage install, as well as a 7 minute video that we shot during and after the installation. Check that out. Brad and Austin from our shop did a great job on this task!

ANDERSON COMPOSITES CARBON JTP WIDEBODY KIT

This was something we had looked at years ago - a carbon body kit from Anderson Composites called the JTP kit (below left) that we had only seen on a few drift cars. There was no information on how wide this kit was, how it fit, etc. We debated this kit on our red 2018 GT in 2019 as well as the Clinched widebody kit (below right), which comes in thermal formed plastic and also full carbon (over $6000).



After a good call with Zach at Anderson, we made the decision to roll the dice and bought the last JTP kit they had in stock, and he gave us an amazing price. It arrived in Late January and it looked amazing. Everything was light and I test fit the rear and was shocked that it added a full 2" of width. The front added a similar amount as well.



Now due to time constraints of these concurrent projects - the cage, splitter upgrades, Haltech upgrades, new wheels needing to be ordered and more - we chose to tackle only the FRONT fender install for now. This meant that the Anderson fiberglass "Type ST" nose and front fenders would be removed (bottom left) and we would need to reinstall the 2018 Mustang GT plastic nose we had on in late 2022 and early 2023.



We had built the tubular bumper beam to fit with the factory 2018 GT nose, and had already modified it to work with that - before we ever added a splitter. That 2018 bumper cover was already painted and we barely had any track time with it, so it still looked great. Just a lot of work to get it re-mounted then fit the two inboard splitter struts through that. Brad got the carbon fenders on the front and we began testing with various wheels and spacers to figure out how much room we had to work with so we could order the first of what became TWO new sets of custom wheels. I ordered wheels from two companies because the first set was taking much longer than promised.



This wheel delay pushed back our move to Hoosiers by about 2 months, as both sets of wheels were late. So we planned on running the same Apex 18x12" wheels we had run in 2023 for the first few events of 2024, until either of the new wheels arrived. Brad used the green "laser" to line up the inboard mounting holes for the splitter but I'll show that install in a section below.

IGNITION COIL BRAND CHANGE + HALTECH EFI UPGRADES

This is another lesson learned - the brand matters. I had joked about this for years: since the LS V8 uses 8 ignition coils (vs the 1 coil for 8 cylinders for 70+ years), how much can the brand of the ignition matter? We've seen coils as cheap as $12 each and as much as $120 each. When we first built this car back in 2021-22, I picked the cheapest no-name branded LS coils on RockAuto, and they lasted a little over 2 years.



During the Haltech 2500 install and tuning work in late 2023 by Rapscallion Motorsports, they had one coil die on the dyno. They found a name brand AC Delco coil from the local parts store and that fixed it, but we were not willing to gamble on the other 7. I ordered Delphi branded coils and we replaced the other 7 in February of 2024 (about $30 each).



The crew that installed the Haltech had it basically shoved inside the glove box and it was time to properly mount that, as well as tie in some additional sensors to the AiM dash. Then we needed to wire in the new traction control dials to the Haltech.



The rear view camera screen we had placed in the center stack panel, but it died in 2023. That was removed and Brad made a flat panel to house the two Haltech dials. Two dials, once changes the allowed Tire Slip and the other how much Engine Power (gain) to pull when that threshold is reached. These are both 12 position dials.



REINFORCE BIG SPLITTER + REMOUNT THE OEM NOSE

As was visible in our late December 2023 test, the splitters were bowing in the middle at speed and contacting the ground. This led us to add lateral reinforcement above the splitter to join the fore-aft 1.5" angle aluminum braces that kept it from bowing front to back.



Brad had already mounted the 2018 factory bumper cover at this point and drilled holes for the splitter struts through the lower grill plastics, shown above right. The splitter was now attached but it has a big 2" gap to the lower GT "splitter lip". We need to cover this gap with an air dam, and since i am short sighted, we would end up dong this task twice.



The lateral brace was tricky - we didn't have room for another piece of 1.5" aluminum angle, as the splitter ramps and new 2018 nose left us less volume to work within. This was when we decided to use a 1" square aluminum tube. It would take more work to fit this - note all of the holes for access to the bolt-thru nuts use to secure it in place - but it ended up saving head space and fit within the narrow confines of the 2018 GT nose.



After that was in we still had the 2" gap. Now I have since realized that I made this much harder than it needed to be, and garden edging (an "L" shaped plastic part that comes in rolls) would have been SO much easier. Stubborn me didn't want the Home Depot solution, so Brad mounted lots of short pieces of aluminum angle that followed along the curving path that the air dam needed to bridge the gap. Needlessly fiddly.



I even drove across town to buy a 4x8' sheet of 1/8" textured ABS to make this piece, but we've since used that for numerous other projects so it wasn't a total waste. The air dam plastic overlaps the lower edge of the factory plastic lower "splitter lip", so we can alter the angle of the splitter for some testing (or so we thought). Brad then reinstalled the old aluminum "end treatments" from the previous nose with one additional brace at the bottom.

INTERIOR PANELS, WINDOW NET, ETC

We had a lot of raw aluminum panels, trays, and even wing uprights that were raw aluminum. It all looked a bit "agricultural" and we planned on semi-gloss black powder coating a while ago. As soon as we had modified the rear bulkhead covers to clear the new cage, all of the raw bits were removed and taken to the powder coat shop.



I told them we were on the clock with races looming and they got it all turned around in just 6 days, which is outstanding. As soon as these were picked up (Feb 26th) Brad got to work installing all of the low gloss black panels.



Everything worked out perfectly except for the fire suppression bottle mount, which was in the middle of the back seat area. With the new diagonal tube placement it could not work, so Brad quickly made another mounting bracket but slid it behind the driver, for better clearance to the cage. That had to be spray painted but you'd never know unless you really looked.

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END OF YEAR RACING RECAP

"I'm not gonna lie, they had us in the first half!" We left 2022 excited to finally hear the 6.3L stroker engine fire up, only to have two miserable dyno sessions in early 2023 and losing the main bearing on our final pull. Then a mad scramble to get the 7.4L engine (which was built to be used in Amy's widebody FRS), finish the longblock, then the LS7 dry sump.



The 2023 racing season included a huge amount of changes and development with this car, as seen in the two pictures above, which was separated by only 6 months! We started the SCCA Time Trial season with stock fenders, relatively narrow 18x11" wheels, no aero, and no oil pressure. We fought problems with the Optima battery, the Holley EFI, and two different intake manifolds. We ended with a 5 second lap time drop at our main test track, some real victories, and a few lap records.



We were also busy all year developing parts for and campaigning Amy's 2023 BRZ in another SCCA TT class, but even with no wins she took the regional championship for T3 class. And by some good fortune I took the M1 championship in Trigger. I won the M1 class 4 of 8 times, but one of those was in Stan's borrowed 2020 GT500. With the 2 drops I actually only won the class by 1 point, so Stan really saved the year for me with that offer to drive his car for one session that day. The losses I had were all in borrowed cars, mostly Amy's T3 BRZ.

I had paid for and planned to go to the SCCA TT Nationals, but bailed out due to the oil pressure issues. We fixed those only a WEEK after TT Nationals, but so be it. The car wasn't ready and I would have been TROUNCED. I went in 2024 but well I'll save that story for another time.

POST SEASON UPGRADES

We had a number of things we wanted to tackle to get ready for the 2024 season. The problems we had with the Holley EFI on this car were pretty epic. If voltage ever got under 10 volts while cranking the starter, the tune would simply DISAPPEAR. This happened regularly on 3 different cars with Holley EFI. We had numerous wiring faults in Holley EFI harnesses. And the fact that Holley EFI will ONLY work with Holley dashes is a huge disappointment (and an "undocumented feature") that wasn't fixed until late 2024 (too late to save me as a customer).

HALTECH EFI UPGRADE AT RAPSCALLION

There were several upgrades we had in mind that almost any other high end aftermarket ECU could handle: traction control, auto-rev-matched downshifts, flat throttle upshifts, launch control, and of course being able to communicate with an AiM dash - and that brand's industry leading predictive lap timer, logger, and more. We picked Haltech EFI and we bought that from a relatively new shop called Rapscallion Motorsports.



We waited until the end of the season to upgrade. We mounted the AiM MXG logging dash beforehand, and dropped the car off on December 5th, 2023 for this work - two days after the last NASA event. Billy at RMS did a "Baseline pull" with the Holley EFI to get some numbers, check data, and turns out - the engine was down 110 whp! It only made 512 whp, and with some investigation that found that the #4 coil was dead, and all 7 others had heat issues (they would warm up and crap out). Ran the Dec 2nd NASA at ECR event like this!



They replaced the one bad coil and got the Haltech 2500 Elite EFI system installed. Then they wired in the various sensors, tied into the AiM MAX-G dash with CAN, and tuned the same 7.4L HPR LS7 based engine. The new setup made 607 whp on their DynoJet, which is a bit of a "heart breaker". That's within 10 whp of what the engine made previously with the same MSD / 103mm throttle body setup on another dyno.



After we got the car back to Vorshlag we replaced the remaining 7 coils with Delphi branded coils. I had been cheap when we built this car and used the absolute cheapest RockAuto $18 coils, and now I stepped it up to the $40/each coils. Big spender!



We did a lot of clean up work after the Haltech install in January of 2024, but I'll talk about that in the next installment. The RMS work was finished Dec 29th and we did a track test as I was picking up the Mustang....

DH TRACK TEST TEST #4 AND TRIGGER TEST #5 - MSR 1.7 - DEC 29, 2023

Last track test of the year but it was a busy one! This was a Friday, and the last day of the year we could be on track. Amy and I both drove the Darkhorse to do some tire testing - on a new set of 305/315 Trofeo RS tires and a new set of 295mm A052s tires, and the results were.... very close. We were joined by Vorshlag shop manager Brad and engine builder Erik from HPR.



I also drove Trigger in several stints while Billy from RMS tweaked the new Haltech 2500 EFI tune and a new traction control system he whipped up. Trigger ran a best of 1:15.10 and the DH ran a best of 1:19.6, which was good for both cars considering the cold weather and newness of the tune on Trigger.



I won't get into the Darkhorse testing this time but the Trofeo RS was slightly quicker than the A052 tires. What mattered more was how Trigger was driving after the Haltech upgrade - and the traction control that we dialed in all day. This lap below was from my 3rd session.



If you watch the video above, on my second and best lap I had to back out of it a little to keep from running over a Corvette, so that 1:15.1 was a little compromised. But hey, traffic happens on a lot of our test days as well as at competition events.



Having Brad there shooting pics with a real camera, we noted a lot of things back in the shop the next week. There was a lot of deflection in the big splitter at speed. If you click on the high rez versions of the pics above, the center is deflecting down so much at speed it is touching the ground. Air is also getting above the splitter when it deforms like this, which isn't good. We addressed this in 2024 with a lot of added structure on the top sides of both splitters.



And the flames that we had been hearing about all summer were finally caught in pictures by Brad here. This is always in decel / braking zones or downshifts, and it is harmless. But boy does it freak out racers behind us!

WHAT'S NEXT?

This is a good place to stop, as that Dec 29th test event was 2 days before the end of 2023 - and as I write this, we are only 3 weeks from the end of 2024. Time sure flies. There is still a whole YEAR'S worth or racing (2024 season) and development to show, and it was quite a bit.



In February 2024 we tackled some major safety upgrades on Trigger with this TrackSpec roll cage kit that we fit and welded into the chassis. As usual we were in a hurry and weren't able to take the 100+ hours needed to lighten the chassis properly before adding the cage, so this nearly 175 pound kit added to the already portly chassis' total weight. We also took the time to powder coat a lot of sheet metal panels and wing uprights, so at least it got prettier.



Above is a preview of what the car looked like by June of 2024 - with a full carbon fiber body. This Anderson Composites all carbon JTP widebody kit was sort of on a gamble - there were not reliable published fender width increases. I bit the bullet, we added it and it was more than wide enough to clear the 335mm front and 345mm rear Hooiser A7s, which we added to Jongbloed 18x12.5" Front and 18x13.5" Rear wheels for use in NASA and Apex events. We also went to wider 18x13" wheels for our 200TW street tire setup, again using 315/30R18 A052 Yokohamas. These changes, plus several more, helped us drop even more lap time and reset almost all of the class track records we set in 2023.

We will cover much of this in the next installment. Thanks for reading!

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That seem silly to you? Well it is - but that's how rules often end up. They want you to have the penalty of the weight of the windows and door panels in the door, so you never bother to take out the stock stuff. We can't run with the "windows up" in either SCCA autocross or Time Trial, but alternate materials ARE allowed in CAM, so we ran these lighter Lexan side windows.



We ended up with a silly solution like this - legal Lexan side windows that never roll up. A simple aluminum bracket bolted to the window holds them inside the door. They can come up and down slightly, but can't be held up extended. It is legal and only added +5 pounds per door.



Likewise, we do have to run inner door panels in CAM class, but the material is open - so they do not have to run the OEM door panels. We used aluminum for an upper top cap section, to close up the window gap a bit, and ABS plastic for the panel itself. This was also 5 pounds per side.



Since we were going to the trouble of making a door panel I asked Brad to make a hole and mount the factory door latch assembly, which he had cut out of the OEM door panels. That makes the door easier to open from the inside, which is a win. Ideally we would have added some nylon strap "door pulls" but the doors are never going to have windows, so we just pull them closed by grabbing the top of the door.



Personally I feel that SCCA TT should allow for gutted doors and NO side windows when you have full Level 3 safety updates - a full 6-point cage. That way we could make the cage SAFER by pushing the cage's door bars out to the skin of the doors. We've done this on numerous race cars, like this E46 above.



Pushing the door bars out to the door skin gives you an extra 8-12" of lateral room between the driver and the door bars (this EVO X had fully 12" of cage pushed into the door cavity), but the SCCA is still thinking that Level 3 safety equipped time trial cars are "street cars". Someday they might get it - caged cars do not belong on the street, so why not let the cage be built even safer?

SCCA TT, MSR 1.3, NOV 11, 2023

All of the prep work above was done to get the car ready for this last SCCA TT event of 2023. I was hoping to show the gains from the new "improved aero", but due to traffic and rain, the car wasn't really able to show its full potential on the tiny 1.3 mile MSR course.



And while I did win the Max1 class and set FTD by over a second, the video below shows how badly my best lap of the day was botched (aka: blocked).



Even a year later while writing this I'm still frustrated watching the above video. This car had a sub 1 minute lap in it that day, but this 1.3 mile course is so tight it is nearly impossible to pass if you catch the back of the field. It really has to be perfect on lap 1. That lap still set an M1 class lap record on this course, but I'll try again for the 59 second lap another time.

BUILD A BIGGER SPLITTER FOR NASA/APEX/GTA

We had some success with the 6" extension splitter as shown in the last post, at an Apex Lap Attack event in October 2023. But that series had essentially no aero limits once you are bumped into the top LA1 class, and we could also run Hoosiers and other race tires. Likewise, NASA TT1 class had a more generous aero allowance than SCCA Time Trial. We also had our eye on GTA's "Super Lap Battle" Limited class, who runs at COTA in the early months of each year.



Jason and I gathered up the rules from GTA Limited and NASA ST1/TT1 and figured out we could make a compromise splitter that was 12" extended forward and a significantly wider. Now, practically, I still wanted to be able to drive the car into our enclosed trailer with the splitter on, so we measured our lateral clearance in there and made this "big splitter" only a few inches wider than our "little" SCCA splitter.



The finished 12" extension splitter (top, above) looks very similar to the 6" long CAM / Max legal splitter (bottom, above). These have the same Professional Awesome "large" plastic splitter ramps and minimal aluminum structure - we would later go back and add a LOT more structure to stiffen these both up.



We started with another sheet of MDO, used a 12" measurement forward and cut out the outline. We were still adding the ProA ramps on top of the splitter, but again we recommend flush mounting them on the bottom - which we did later.



Brad got this built and painted in a full day of work, and a new set of longer ProA splitter struts hold it on the leading edge.



We were still just barely able to load this into our trailer with the splitter installed, but due to the extra width we initially left in this version, it would not clear the trailer's internal fenders. That meant we had to load it backwards, which I did NOT ever want to do again! We came back later and removed those extra lateral inches to allow for forward loading, which works so much better.

NASA TT AT ECR, DEC 2, 2023

Did a single day of a NASA TT weekend, entered in TT1. We also entered the Darkhorse in TT3 but Amy only ran it in HPDE4. Both cars were teched and log booked for the year - in December.



I gridded Trigger in P2 for the first session, as there were some bonkers TTU cars gridded behind me. 30 cars signed up in TT. Weather was a chilly 40F in the first session. I had the 2nd fastest time in that session (1:59.85) back from P1 by 2 tenths, even with a weird and unexplainable 4 off, and my best lap was not until until Lap 5 - which these A052 "street tires" don't like to run that long.



I gridded P2 again in the next session, and I was stuck behind an Ariel Atom for several laps while his tires warmed up, and it took until Lap 3 to get around him. My fastest lap was again very late in the session, with a 1:59.1 on lap 4 followed by a 1:59.3 on lap 5, then I ran out of fuel. Made it back to the scales in fumes, still 546 pounds over my TT1 minimum weight for the power this car makes, and that was a new personal best here. I put 15.5 gallons into a 16 gallon tank after that! That was the quickest TT time up to that point, so I would be starting P1 in the next session (no traffic!) But then it rained HARD and nobody went out in that one.



At the same time I listened to another racer who saw the car squatting the rear at speed, and I admitted that I had an aero imbalance with a high speed push - and I listened to this fellow who convinced me to take the upper wing element off for the next session. I took that off, and raised the main element to the highest angle of attack. I went out in the 4th and final session in P1 at 4:20 pm to a dry track.



And while the "aero balance was better", OMFG the car was slow! In this session I only managed a best of a 2:02.4 lap - fully 3 seconds off my own pace earlier! About half the field DID go faster in that last session, so it was a GOOD session to push in. My silly "aero test" was costly, and I threw away the session. Two TTU cars got faster in that last session and snuck ahead, so I also threw away FTD. I still won TT1 class, but I felt pretty crappy about that lost session - what time could this car have run if I hadn't taken the 2nd wing element off??



After switching out the crusty RE71R tires in a previous session, we put the Pirellis back on the Darkhorse. She ran a full session on those, then I went out with Amy in the last HPDE4 session, but we could both feel a problem on a front tire right away. We came right back in to check, and sure enough, it had chunk and corded a front tire. We swapped back to the old RE71R tires for the drive home, so I never got to drive the Darkhorse on ECR for a baseline lap.



Big lessons learned here, and I won't make the mistake of chasing a "perfect aero balance" by crippling downforce at one end. I had hoped the new "big" front splitter would make more of a difference than it did, but we kept at it in 2024 and found more front downforce in later iterations of the car. Still, to finish the year with a TT1 "win" (in a class of one) and a new personal best at this track was nice. Turns out we did this on 7 cylinders, as we had a dead ignition coil...

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Project TRIGGER Update for December 4, 2024: While I have been busy writing various project updates and articles for Grassroots Motorsport Magazine, we have been busy racing and developing our S550 Mustang #Trigger. I took some time in November to bang out an update, to get this project caught up with the end of 2023 before we slip into 2025!



On our last update, we left off on work and events completed through mid October 2023, after we had finally solved both our dry sump oil pressure issues as well as added aero. That combination of changes led to a big lap time drop at MSR Cresson, an Apex Lap Attack win and FTD. The let us finally tackle new areas to develop on this car, instead of just chasing the same oil pressure issues like before.



The very next day after that Oct 2023 Apex event we got to work on a big round of aero enhancements, then tackled the final SCCA TT of 2023 and secured a win, FTD, and the regional championship. Then in early December we attended a NASA Time Trial and won TT1 class on street tires. Shortly after that we removed the Holey EFI and installed the first of two Haltech EFI systems, and our AiM MXG dash again, with tuning work from Rapscallion Motorsports. Let's get to it!

FINDING BETTER AERO BALANCE

Coming off the October 14th win and "FTD" from the Apex Lap Attack event, I was super stoked - all I had ever gotten were 3rd place trophies (a series we sponsored) with them in 2023, running in 2 other cars. Even with the quickest time of the day, we knew we had barely scratched the surface of Trigger's potential, and the rear aero imbalance needed to be improved. After the event pictures came in from the Apex track photographer, some of the issues were visibly apparent.



We could see the rear suspension squatting at speed with that usually high mounted wing uprights we made to the rules limit. The day after that event we quickly came up with plans to change the rear wing height and fore-aft placement, upgraded the spring rates to counter these rear aero loads - as well as made plans to build a larger splitter to use in Apex, NASA and GTA events. We could also see the upper wing element was deforming above 125 mph, but that was a simple fix.



We also worked on improving the front splitter's rear mounting plate, added splitter end plates, reinforced the splitter on the top side to reduce deformation under load, and then opened up and made proper vents for he new carbon front fenders. All of these changes would hopefully improve front downforce.

LOWERED REAR WING UPRIGHTS - VERSION 3!

The wing uprights we used at the October 2023 track test and October Apex event were super tall - built to the limit of the rules in CAM-C and NASA TT1. These were fully 10" above the roof and the wing went 6" behind the car. Both October 10th test and the October Apex event showed we had WAY too much rear downforce, so we decided to lower the wing mounting 6" down as well as move it forward by 7". This will change the lever arm on the wing and reduce downforce.



As you can see in the CAD drawing above and the version 3 uprights below, this was a significant change. Not everyone noticed this, but we sure did. The DAY AFTER the Apex event we cut our version 3 uprights for this same 9LR dual element carbon wing.



It didn't take Brad long to transfer the mounting holes from the Ver 2 uprights to the newer, lower units. Those were then bolted onto the chassis and then the dual element wing assembly was bolted to that.



Once Johnny at 9LR explained to me why the top element was bowing, the last "upgrade" we needed was to install the dual element Nylon spacers that they had supplied. These fit into the slot gap between the two elements and provide the smaller upper element with strength from the bigger / stronger lower element. Lesson learned: Read the instructions.

REINFORCE SPLITTER + UPGRADE MOUNTING PLATE AT THE CROSSMEMBER



Even after minor use in August (above left) we could see that the rear splitter mounting plate was bowing. And after the Apex event (above right) we had a major deformation in the middle of the splitter itself - it was sucking the center down and scraping the track. That's not what you want.



The rear mount repair was one that Brad and I brainstormed about. We added some mounting holes and removed some others. The center portion that was bowing down was reinforced by adding some 1/2" thick spacer blocks that the new bolts enough through, into the bottom of the subframe.



That rear splitter mounting bracket setup worked perfectly for more than a year before I tore it up in a crash (Oct 2024 - more on that later!) The reinforcement was done initially here in October 2023 with some extruded 1.5" x 1.5" x 1/8" wall aluminum angle, bolted fore-aft on the top side of the splitter. The countersunk bolts went through the splitter from the bottom for a smooth surface.



That worked pretty well for a few months, but we added even more reinforcement when we changed the front fenders in early 2024.

BUILD FRONT SPLITTER "END PLATES"

This aero change was a bit controversial when I first posted it, but Jason here at Vorshlag had his reasons for adding this. In the year since we added these "end plates" to the splitter on Trigger it has become more common to see end treatments like this, and we have even altered it since this initial design. We also took inspiration from OEM designs here.



At the time we ran an 18x12" Apex wheel and 315/30R18 Yokohama A052 "200TW" tire with this "GT500 style" (Anderson Composites Type-ST) front nose and 3/4" wider fenders. As you can see above, the tire protrudes from the front covering of the bumper cover and fender a good bit along much of the tire's height. And that is NOT beneficial for drag.



We wanted to make both a "Tire wall" (aka: wheel wicker) as well as an endplate for the splitter. The endplate captures some of the air on the top side of the tire wall and splitter and holds it in the working zone there, and more importantly it promotes air evacuation from the wheel well, to create more front downforce. And yes, it does add some drag, but we desperately need front downforce. We used .080" thick aluminum sheet to make the curved "tire all" and the vertical end plate.



We did not come up with this out of thin air - the OEMs have been doing this for a while. The image above left is of the C7 Corvette Z06 and a 2020 Mustang GT500, both of which have smaller versions of this exact same design. We made them into a welded aluminum piece that bolts to the fender and lays atop the splitter.



The change in "high speed front end grip" (ie: front downforce) was significant and noticeable. It plays a part in the aero package of the car, and works well for the overall aero balance. It isn't perfectly balanced at speed, but it is a lot better - and the mod below helped that even more.

LARGER FRONT FENDER VENTS

Another front downforce enhancement trick is to vent the fenders. Air from the splitter tunnels dumps into the front wheel wells - some of it is going to the brake deflectors and out through the brake rotors and wheels. Much of the under car air that ends up inside the fender liner of front these the wheel wells, and needs to go somewhere - otherwise it causes lift.



We had these "GT500 style" fiberglass fenders that already had an existing (very small) vent opening - so I drew out what we wanted to do in blue tape and Brad cut these triangular openings, which were much larger.



This gives the high pressure air a place to exit, but the flow of air needed some direction - after making mock-ups in cardboard, these curved ABS plastic deflector panels were made and bolted into the triangular openings.



The leading edge of these deflectors met at a large rectangular hole in the factory fender liner. That opening was heated up and "bent" to match the shape of this opening with a heat gun. A 2-piece plastic rivet connects the fender liner with the ABS plastic vent panel (yep, that is all we have needed - been using this vent for over a year now).



You can stick your arm in this opening, and the curve shape of the exit, the actual opening, and overall layout was guided by aero engineer Jason. This also made a bigger aero balance adjustment than we had hoped, but it would be a while before we were able to properly test this on the MSR 1.7 course.

MAKE FANCY PANELS AND DOOR WINDOWS

Before the last SCCA TT of 2023, to make this car 100% squeaky clean legal and protest proof for CAM-C class (and thus Max1, as we run the "alternate ruleset), we needed to add lightweight door windows and inner panels. Before October, the car was too slow to protest, but now that we were much faster, it was time to close some up rules gaps we had on Trigger.



We ordered these Lexan side windows from Plastics 4 Performance out of the UK with the rear window and quarter windows. These were 4mm thick and came with a protective film on both sides, which we never took off - because we have no intention of ever making these go up or down - they just need to be sitting inside the door. Glorified ballast.

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APEX LAP ATTACK - MSR 1.7 CCW - OCTOBER 14, 2023

Two months had passed since our first Time Trial win (SCCA TT, where we ran a 1:18.933 best lap) in Trigger, built around that series Max1 rules with 200TW tires and max CAM-C aero limits. We now had access to all 620 whp of the HPR 454 all the time, with the oil pressure issues fixed. Two days before this event we had tested the new 4 stage external A.R.E. dry sump upgrades at this track - now we could finally sustain oil pressure around long left hand turns (something the LS7 based "Dry sump" could NOT do). I didn't even unload the Mustang from the trailer from the test day earlier that week, because it went so well.



This Apex event was on our normal test track - the Motorsport Ranch 1.7 CCW course - where we scored that first TT win in August (barely). I was hopeful that the oiling upgrades and aero tweaks we added in September would improve cornering and braking. We had never placed well at any Apex event in other cars - running in our 2006 C6 or 2023 BRZ I had podium'd in one of the five classes, but never had a win. I hoped this time would be different. The 1:16 lap from Thursday might be competitive, if we can back it up?



They shoved Trigger into their fastest class (LA1) even with street tires, running against lighter cars with the same or more power, the same or more aero, and on Michelin slicks or Hoosiers. I was worried that I'd be lucky to score 2nd or 3rd in class, with these obvious disadvantages. With only two laps in this car EVER that didn't suffer from the low oil pressure trigger, and almost no laps with the new aero, I was treating this more as an extended testing session. I didn't want to get my hopes up, but I got to grid early and gridded myself P2 for the first session - after the first session, cars are gridded by best lap times.



The fastest driver at Apex Lap Attack events for a while was a driver in this stripped yellow C7 Z06 race car on slicks, full Motec, built engine, sequential transmission, proper race tires, Bosch ABS, and full aero. I built a big gap on the out lap but caught him pretty quickly going into Big Bend. WHAT IS GOING ON!? During hot Lap 1 the gap closed up and he POINTED ME BY? How... how is this happening?!! I saw him dive into the pits without completing a full lap, so he had some kind of issue.



Passing him slowed up my first lap (1:17.0), but with no traffic I pushed hard on hot Lap 2 (1:15.98 best). I was freaking out and came into the pits, and that was the fastest lap for the first session - and a new PB by a few tenths. That put me P1 on grid for Session 2, where I pushed harder on lap 1 and got to a 1:15.564, another new PB by a half second. That lap was with traffic and a pass, too, so Trigger car was actually WORKING.



I was still under-driving the high speed corners, so the 3rd session I was bound and determined to push more - but had a botched downshift on lap 1 (1:17.0), then pushed on for 2nd hot lap and found a 1:14.693 - yet another new PB! Session 4 was a wash, but that 1:14.6 time was the Fastest Time of the Day by fully 1.1 seconds! YES YES YES YES YES!



It wasn't a perfect day, but the weather was pleasant, and we even had a partial eclipse. The eclipse was weird, but the car worked well - even with pretty terrible aero imbalance and high speed understeer. My minimum speeds in high speed corners were all still too low, but I was still learning the limits of the aero.


In-car video of the new PB for Trigger - https://youtu.be/e7noUqhjUe0

This new Personal Best lap time made for an improvement from the August SCCA TT event by more than FOUR SECONDS. That was simply wild to me and the whole crew, and showed us how much potential the car had and how much difference aero can give you.



Zero issues all day, solid oil pressure even with 1.53 g lateral and 1.58g braking, and even with 200TW street tires we still managed to win. Very happy with the results!



My closest competitor that day - Aamer - sparred with me at this event / course again in 2024 - we both found time and I was on Hoosiers that time, so Trigger dropped even more. I will cover that another time.



This event was the absolute HIGH WATER MARK for me in 2023, and if the car had been this well behaved a few weeks earlier we would have taken it to the SCCA Time Trial Nationals at NCM (I had cancelled my entry with the oil pressure problems and delays in getting the dry sump system finished). I'm planning to make that event in 2024, as the car is quicker and more sorted now.

OIL PRESSURE ADJUSTMENT ON DRY SUMP PUMPS

One of the things we noted once our tuner Jon looked at the mish-mash of jumbled data that is Holley's norm was that the oil pressure was too high on track at speed.



Erik from HPR recommended that we dial out the relief valve on the ARE pump, which is accessible from underneath. Each turn is supposed to drop 20 psi, but we got the dang thing turned all the way out with the minimum threads showing and it was still too high. This led to some valve cover leaks and a little wasted power, but I'll take that over low pressure! We fixed this fully in 2024 - I'll cover that another time.



Much of what we learned on dry sumps is shown in this short 1:22 minute video, linked above.

LAP TIME COMPARISON

As always we like to list lap times with video links for the car in the forum post plus a few others to compare to at our Motorsport Ranch Cresson 1.7 mile, CCW test track. I have 800+ laps over 25 years at this track, and drove all of these laps listed below at this track / configuration, with either AMB transponder or AiM Solo lap times. The cars in this list include our NASA TT3 prepped 2018 GT, 2024 Darkhorse, and of course the star of this entry, our 2015 Mustang #Trigger - all 3 tests on the MSR 1.7 CCW from this post are in bold. Just know that we have gone significantly faster than this as I write this, but I'm only listing what we have covered so far. We get to tackle a lot more events at ECR and MSR later in 2023 and unto 2024.

MSR-C 1.7 mile CCW:

• 1:20.348 - 2018 Mustang GT, NASA TT3 prep, 305mm RE71R, MCS RR2, 474 whp (fastest this car every ran on 200TW)
• 1:20.677 - 2024 Darkhorse baseline stock, 180TW Trofeo RS tires, Track Test #1
• 1:18.878 - 2015 Mustang #Trigger, testing 7/22/23, 200TW tires 315mm A052, 627 whp BTR Trinity + 112mm TB, Track Test #2
• 1:18.933 - 2015 Mustang #Trigger, 620 whp, no aero, MSD Atomic, 200TW tires 315mm A052, SCCA TT win 8/12/23
• 1:18.417 - 2024 Darkhorse, -3.5 deg camber with SPL arms + Vorshlag plates, 180TW Trofeo RS tires, Track Test #3
• 1:16.637 - 2015 Mustang #Trigger, 620 whp, with aero, MSD Atomic, 200TW tires 315mm A052, Track Test #4 11/12/23
• 1:14.693 - 2015 Mustang #Trigger, 620 whp, with aero, MSD Atomic, 200TW tires 315mm A052, Apex Lap Attack win 11/14/23

WHAT'S NEXT?

I worked a long time on this massive 5 part forum entry and still barely got us through October 2023. There was a lot of ground to cover, especially with the aero and dry sump work, but I wanted to get to our "break through" event where everything finally started to work - the October Apex event. I was hooked after this win, so we started to develop a splitter package for Apex and NASA, both of whom allow for more front downforce tricks.



In December we attended a NASA Time Trial and won TT1 class on street tires. Then we purchased and installed wider bodywork to fit 335/345mm Hoosiers. We also lowered our rear wing to reduce rear downforce, and changed springs and some other things to work on the aero and suspension balance. In December of 2023 we removed the Holey EFI and installed the first of two Haltech EFI systems, and our AiM MXG dash again. I will cover all of that and more next time.

Thanks for reading!

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With the timing cover sprocket + cover swapped, the redundant internal oil passage covered, new balancer and cog drive installed, and new ARE oil pan bolted to the engine - NOW we could finally bolt on the ARE pump to the block. Putting the cog belt and pulley on the pump should be easy, right? WRONG.



The shaft on the ARE pump is made with a keyway, and comes with a key installed. Yea, pull that out and throw that away. The cog belt pulley that comes with the kit doesn't have a keyway, and is made to be an adjustable press fit. This is an "undocumented feature".



The pulley itself is this multi-piece assembly. The bolts that hold this all together are too long and hit the pump housing. So shorten the bolts 5mm or buy new bolts that are only 30mm long. Some trips to the hardware store and overnight shipments happened for weeks while we chased down all of these strange issues, fitting upgrades, etc. Whoever says putting a remote dry sump pump on is easy is lying to you.



Once we finally got the new pulley system installed with the right hardware and no key for the grooved shaft, we could slip the belt on (yes, you just slide it on by hand - there is no tensioner) and give it a twist. The top right pic shows how much tension you want. If there is more than a 90 deg twist, shim the pump away from the block with washers until you get this tightness. If you get less than 90 deg twist, call ARE for a new belt.



After all of that running around, machining multiple parts on the lathe, custom tools and bolts, a new product we developed to block off that internal passage, a new motor mount, the new front cover / sprocket, totaling two weeks of chasing this task - we had the pump bolted onto the block, the belt drive corrected, and the oil pan on.

PLUMBING THE DRY SUMP SYSTEM

All we have left is A LOT OF PLUMBING. There are so many ways to do this wrong, and only a few ways to do this right. We could write a book on the numerous mistakes we have seen done with dry sump plumbing. I showed an engine on a stand upside down at the top of this section, and HPR did the plumbing on that engine for their end customer - which removes some chances for mistakes. The plumbing diagram from ARE is painfully incorrect, still to this day.



This part of the dry sump install is very fiddly, but because we could spec and install all of the plumbing and make the hoses without an external vendor supplying things (wrong) from some kit, it had the least amount of jack-assery of this whole upgrade. We had HPR to help guide us on this plumbing work as well.



Plumbing is still a time consuming job, and this ate up about a week of time - mocking up fittings, ordering parts, then building and testing all of the hoses. Then ordering more parts and making the final routing. Why not keep an infinite number of fittings on hand? Well some of these are $40 each and you might need 6 versions of a bend for the same size and style hose. We all have budgets!



We plumbed the 3 suction stages from the pan with -12 AN Fragola hoses to the pump. The main pressure hose from the pump to feed the engine is a big fat -16 AN monster, and the main suction lines to and from the Peterson storage tank are also -16 AN lines. Larger sized hose shave a smaller pressure drop per foot of hose, so the larger diameter hoses should give us the most pressure. I spelled out the routing at the start of this section.



Due to my paranoia about the oil pressure, we stuck with the 5W50 Motul "Sport" oil and put in a new filter for the remote setup, then sent off a sample of the oil to be analyzed. We fired up the engine and checked everything for leaks - none! (we have since switched to 5W40 and might go to 5W30)



The oil pressure looked VERY good, so we called in a gunslinger tuner Donnie to check the Holley EFI system for a quick tune up - he took out the oil pressure "triggers" for the old low pressure safety scheme. That cure might have been worse than the symptoms, and we were confident we'd have enough pressure with the external pump now. We did leave the low oil pressure warning light wired up, and Donnie added a low pressure warning on the Holley dash.



We had spent the better part of 5 weeks removing the parts above and replacing them (except the water pump and radiator hoses) with this external dry sump oil system. There was a lot of cursing, frustration with incorrectly supplied parts and custom machine work, and a lot of overnight orders and stress. This is not an easy job, especially when you are converting from wet or LS7 dry sump to this external dry sump - and we had installed ARE external dry sumps before. It is always a staggering amount of work - so you were warned! (all of those old parts shown above have been sold).



Brad painted both sides of the "small" splitter and reinstalled that, then I took the car for a short test drive to get some fuel. We had the 2024 Darkhorse for a whole week by this point, and I was beginning to wonder if Trigger would get replaced with this high tech S650? The Darkhorse ran a 1:18.4 lap with stock tires and camber in November 2023 - a time which we had not beat in Trigger by August of 2023!



With the added weight of the aero parts and external dry sump system we took a weight of the car before loading up. It was heavier than ever, which made me a little worried, but I had faith that the oil pressure issue would be fixed and we could be onto a major time drop on track!

TRACK TEST # 4 - MSR CRESSON 1.7 CCW - OCT 12, 2023

This was what we were building up to - a short run on our 1.7 mile test track on the Thursday before a scheduled competition on Saturday October 14th. I ran the car out to the track myself early on a Thursday to run ONE session, which would give us part of the day Thursday and a full day (Friday) to fix anything wrong with the car.



I was nervous, as I had signed up for the Apex Lap Attack event for that Saturday - we couldn't really afford to have something major go wrong, otherwise I'd have to scrub that event.



After a semi-quick first lap spent watching gauges around the big left hand corners, I sped up and took 2 hot laps at speed - finally full power without any oiling issues!! It was such a rushed test that I took no video and I don't even remember who took the 3 pictures of the car on track. Looking at them now the massive front end lift and rear squat shows a terrible aero balance, but I was so excited that the car WORKED that I didn't see that until days later.



The aero + lack of oil pressure issues - and the removal of that engine retard from a sub-30 psi trigger - was worth a nice TWO SECOND DROP in only two shake down laps. I was not near the limits of the tires and hadn't started pushing entry speeds into corners to take the advantage of aero. We still had a lot of work to get this car dialed in with respect to suspension / aero / etc, but at least it is "semi-fast" and reliable now. Whew!

The Holley dash was still a hot mess and logging the oil pressure / syncing that with video was still impossible for me. But I watched the dash readout like a hawk while driving, which is partly why the times were a bit slow. Yes, even with the 2 second drop in this car's Personal Best, I was off pace.

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WHY DID THE LS7 DRY SUMP SUCK?

The two main components we surmised that were causing the most low oil problems with the OEM LS7 based "dry sump" system were the factory LS7 oil pan (below left) and the 2-stage internal oil pump (below right). This was after looking at reams of data, discussing with our tuner and engine builder, and consulting outside oil system experts.



We had upgraded both items beyond stock - the oil pan had the Improved Racing baffles and windage tray, and the stock LS7 2-stage oil pump was swapped for the higher volume Katech red pump. We had even port matched the pan to pump interface, and of course we had the huge Peterson 3 gallon oil settling tank (the stock LS7 oil tanks are pretty awful). Why was it still so bad?


Our 2006 Corvette's stock LS2 wet sump oiling with Improved Racing baffle ran a 1:19.7 time in competition, and logged oil pressure was fine

But as we noted with data, the oil pressure would dip below 30 psi in long left hand turns on Trigger. After conversing with HPR and others we feel that this was mostly due to the high lateral Gs that these modern 200TW tires can produce. 1.4-1.5g lateral grip is far more than a stock C6 Z06 could ever see without slicks until these new tires came around. Again, our narrow body C6 above with the exact same A052 tires and a wet sump and had no issues - and several of the T2 class track record I set with it in 2022 still stand 2 years later.



The stock LS7 pickup screen is offset a bit to the driver's side, but the engine is slinging oil opposite of that with crank windage. And even with the Improved Racing oil pan baffle, windage tray and crank scraper we still had issues. That high lateral force + the natural windage direction allows the single LS7 pickup screen to be uncovered, and the high flow volume of the pressure stage of the pump would drain the remote oil tank to a point that the engine would lose oil pressure within about 6-10 seconds of left hand cornering. We had run out of Band Aids (bigger hoses + Accusump) and further track use would damage the expensive HPR 454" engine.



The first part of this fix was to move to an ARE Dry Sump pan, and replace stock LS7 unit. Now if we were running in a series that banned external oil pumps this company does make a "better" pan for use with the internal 2-stage LS7 style pumps, but the time for half measures was over. With the added grip of the new aero + Hoosier A7s we had planned for another series, it was time to jump all the way in and add the external oil pump with 4 stages; this pan was setup for 3 suction stages and a single pressure stage.



This particular ARE pan was part of some old / unused inventory that Erik at HPR had on hand. We noted that the 3 suction stages were setup with -10 AN lines / internal screens. We upgraded to their more modern -12 AN screen / fittings, as we planned to run all -12 lines from the 3 scavenge stages to the pump, then -16AN lines for the combined suction line to the tank and back to the pressure side pickup.



ARE dry sump systems supplied us with their normal "Y-body" (Corvette) pump, which has -12 AN inlets for 2 of the 3 suction stages, a -10 line one scavenge and the pressure output, and a -12 on the combined scavenge output. We upgraded all of the -10 outlets on the pump - going to a -16AN on the pressure output and a -12AN on the weirdly small 3rd scavenge stage. The image above right shows what we planned for. Maybe there's less room on a Corvette to plumb all of this, but on our S550 Mustang we had ample room for the bigger -16AN lines, so we made that upgrade.



This image above from HPR shows the the same ARE pan plumbed for an identical ARE 4 stage dry sump pump, with 3 suction stages plumbed from the pan to the pump, then the one output stage to the "inlet" side of the block (where the oil filter would normally feed). This setup had the one -10 suction stage line (the middle stage) and the smaller pressure output fitting at the pump, but a -12 line run to the feed. We upgraded all of these on our setup.

MAKING A NEW ENGINE MOUNT

To fit an external dry sump pump to an LS engine, the factory air conditioner almost always has to be removed - as the passenger side of the block where the compressor rests is the best spot for an external oil pump. Why? Because of how the engine rotates internally slings oil to this side of an oil pan, so the scavenge ports (in this case, 3 of them) need to be on that side, and those need to be plumbed with as short a runs as possible to the pump.



As soon as we tried to mock-up the 4-stage ARE pump we had an issue - it ran into the Vorshlag LS550 swap mount on the passenger side. If we weren't stuck with this Corvette drive setup it would have worked, but this is what we could get FAST. So we hung the engine from a cross-engine brace and removed the right side engine mount.



This was a tricky fix, as there is a big "cup" in the S550 subframe where the factory hydraulic rubber bushing sits, and which we kept on our LS550 swap mounts. That had to come out, so we made a somewhat unusual motor mount design, which uses a poly round bushing that goes in almost all of our other LS swap kits. That nests down inside this cup. The design was drawn up and CNC plasma cut.



Then the tubular motor mount for that sleeve was built, which bolts on the block side with 4 bolts. The mating piece that goes into the cup in the S550 subframe is a separate piece. These two bolt together for a non-solid engine mount.



We kept the drawings and fixtures in case we ever need to add a dry sump to an LS197 or LS550 again with this Y-body pump setup, we can make these again. With the ARE 4 stage pump finally mounted, we could bolt that up with the new engine mount in place and lay out all of the -12 and -16 fittings, so those parts could be ordered.



Unlike most myths, we cannot possibly stock every single type / angle / size fitting and hose end at our little shop. We do have a good number on hand, but mostly order fittings on a purchase order from Fragola for any given job. We were tight on time so we overnighted parts from a wholesaler that is in town, paying 2x as much, but time is money.

SWAP OUT THE LS7 TIMING COVER + BALANCER HUB DRIVE

It was time to pull off the LS7 front timing cover, which has an enlarged front section to house the wider 2 stage pump (a wet sump LS has a single stage pump, which draws oil from the wet sump pan and pressurizes it to the engine).



FIRST set the engine to TDC on cylinder one, as the timing chain has to come off and go back on. Mark the timing sprockets "dot to dot" when you get everything uncovered. The old balancer hub was pulled and removed, then the timing cover, then the Katech pump came out.



This is the back side of the Katech 2-stage internal oil pump for an LS7. A wet sump single stage LS pump looks very similar. That hole shown is where oil pressure feeds into the block - this changes with an external oil pump, which feeds pressure through a hose to a port on the block where the stock oil filter is located. Keep this in mind for steps shown below.



Behind the Katech pump was the longer LS7 style lower timing sprocket - which drives the oil pump on the extended section shown. The external dry sump setup is made to work with the shorter LS2/LS3 front timing cover, and that means changing to the shorter LS2/LS3 lower sprocket for the timing chain. That also means that our "long snout" LS7 style crank has the 3rd keyway removed, as that gets in the way.



After the longer LS7 sprocket is pulled, the shorter lower timing sprocket is warmed up to about 200F in the toaster oven, and then it can slip over over the (cold) crank. That gets a bit of a whack to get it started... while still warm (and slightly oversized).



Then the old sprocket is slipped on backwards, a big washer, then a crank bolt is used to press the new sprocket onto the crank - which has a light press fit.



The timing chain and upper sprocket were reinstalled, as well as the tensioner. All of the bolt torques are shown above. And again, the sprockets were already aligned "dot to dot". Something HPR warned us about was that we had to cover the oil feed hole from the LS7 pump, which is the same as the wet sump LS engines. That hole is marked in image above right.



We didn't see a good part to do this with, so we created a new product and now sell that at HPR and Vorshlag for these "dry sump upgrades". It is bolted on with some RTV on the backside, and stops a big pressure dump behind the timing cover. Now some shops don't know to do this block off, and there were some wide eyes when we posted this on socials at the time, and we sold a number of these block off plates that likely solved some issues - again, thanks to HPR's guidance.



The new balancer provided by ARE came with the cogged belt drive behind the balance, to drive their Y-body pump. A cogged drive on the front side of the balancer would work better for a car like this - we have the room. But we were pressed for time and this Y-body setup was in stock at ARE and all we could get for weeks. ARE also included a spacer for our "long snout" crank - of course we also needed to machine that to actually fit.



Next step is to install the new balancer hub and cog drive we have to measure to make sure the press fit is right. THIS IS ALWAYS WRONG. "Trust, but verify" with any off-the-shelf part, and we have yet to get an ATI balancer that actually fits a factory spec'd crank snout. Time on our lathe and get this .015" mismatch down to a more manageable press fit of only .002 to .003". Otherwise you WILL break the end of the crank and/or strip the threads off.



To get the hub installed onto the crank you need a longer crank bolt. The LS engine family has two lengths - the normal "wet sump" short length and the longer LS7 "long snout" length. To install the balancer hub you need to use the longer LS7 bolt in a short snout crank and for a long snout, well... we made a special custom longer bolt for HPR by welding two bolts together, so we borrowed that for our long snout crank setup. The longer bolt is used to pull the balancer hub down to a certain point, then the proper length ARP bolt goes in to draw it in the last fraction of an inch.



The shorter LS3 front timing cover was installed - use the LS1/6 or LS2/3 timing cover version depending on what cam sensor you have in the front cover. Then the "long bolt" was used to pull the new ATI balancer hub installed. We had a .002" gap from the cog drive to the lower timing cover seal, which was in spec. Once the hub is almost installed, switch to the proper length ARP bolt and torque that. The new balancer is bolted to the hub. We also swapped our timing pointer (your tuner will love you if you add this!) to the shorter version.

SWAP THE OIL PAN

This is a big part of the upgrade - getting multiple scavenge ports to pull as much oil out of the oil pan as quickly and efficiently as possible. Some systems use 4 suction stages - one for each "V" bank of cylinders. Sometimes there's even a suction stage from the camshaft valley, if you have an aftermarket block with that segmented off. So a 6+ stage system isn't unusual. But this is a somewhat budget friendly (ha!) 4 stage system, with 3 suction stages in the new low profile pan.



We dropped the front subframe down a tick (when we had the engine hung from the cross brace) and removed the LS7 oil pan. The ARE dry sump pan has a baffle over the 3 suction stages, and the unit itself is shorter. A new FelPro gasket (for an LS1/2/6) with a little RTV to hold it in place went onto that pan, that and the new pan was slipped in place.



Now some of you might wonder - "hey, can't you lower the engine now?" And yes, in some instances the shorter dry sump style pans do allow for the engine to be dropped 1-2 inches or more. We would need all new engine mounts and some other changes. But in this car the balancer would drop down onto the EPAS steering rack, plus our headers and exhaust would be wrong.

And our giant Tremec T56 Magnum would be too low then. So no, we didn't lower the engine. This is a 3600 pound car and moving the center of mass for the 420 pound engine down 1-2 inches is not worth the tens of thousands on costs and fab work for that tiny, immeasurable gain.

ADDING THE COGGED BELT DRIVE

Like camshaft timing belts, a Gilmer drive or cogged belt is a pretty common way to drive an external dry sump oil pump. These cannot "slip" and handle some real torque going through them. If you set them up right they cannot just fall off, but it sure seems scary that there is no tensioner or cover over this belt.




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After finding the perfect placement (consulting with engineer Jason, Brad and me) it was time to cut the openings for the tunnels. These need VERY large openings, as you can see below. Now here is where many of you may disagree with my decision but we put them on TOP of the splitter plane. They are normally placed with the plastic mounting flange just BELOW the splitter plane - but I was worried that scraping of the splitter could damage the lower mounting flange of these $300 tunnels.



That proved to not be the case in practice - we have since remade this with the tunnels bottom mounted, where we routed channels into the bottom edge and flush mounted the tunnels. Brad used a belt sander to shape the lower edge of the splitter leading into the tunnels, which somewhat smoothed out the airflow, but this was FAR from perfect. Again, learn from our mistakes - mount the tunnels with the flanges on the BOTTOM of the splitter.



In the images above we have the ProA tunnels mounted to the top side of the splitter, and on the top right image you can see the brake deflectors clearly in the exhaust area of the tunnels. This led to exceptionally good airflow to our brakes, and overheating is not an issue now. We later noted some front end LIFT that this exhaust of air caused, once dumped into the fender wells and fender liners. We tackled that fix with fender vents at a later date.



The last images I will show are the "edge attachments" we added. A small section of angle is added to the outer edges of the splitter which mates up to an aluminum panel at the edge of the finder/air dam. So now we have the 4 splitter struts at the front, these two push-pins at the fender, and the rear plate that holds the splitter along the back.



I was happy with this method of attachment, the tunnel placement, and the overall shape of the splitter. It would evolve further over time, but it worked pretty well the first time out.



As great as this splitter looked, the biggest aero change that is noticeable from a great distance is the rear wing. It is a little crazy.

C-PILLAR MOUNTED DUAL CARBON REAR WING

This is a monster wing, and we we used the SCCA CAM / SCCA TT MAX rules to mount this as high and far back as the rules allow.



I will be the first to admit that the S650 Mustang GT3 car was our inspiration for this "C-pillar" mounted wing, but this is also done on other GT3 Cup race cars. The advantage is it is not only a swan neck design - which puts the mounts on the top side of the wing, which is doing less work than the bottom side - it also cleans up the trunk mounts. This also works well when you can put the wing way up above the roof, which both rules package we run allows for.



We saw the GT3 wing mounting in late 2022 and reached out in early 2023 to 9 Lives Racing, then procured one of their giant, carbon fiber, dual element wings. We ordered this with large carbon end plates, made for a swan neck mount - which are located on the top of the main element.

Now I took a lot of pictures during this time, but it would bore most of you. And then again some of the things we did might help some competitors figure out what took us a lot of hours and attempts to learn, so I'm not sharing some things on purpose.



Let's cover the highlights. After assembling the multi-piece rear wing assembly we mocked it up the maximum 6" behind the car and 10" above the hood, from the SCCA CAM-C ruleset (and later adopted as the SCCA Time Trial Max aero rules). We made mounts from press board, then upright pieces of the same mock-up material on the outside of the car that the wing hung from.



We took the cardboard then pressboard mock-up pieces, scanned those, and Jason turned them into CAD drawings. Multiple iterations of these were done in CAD before we cut the first uprights on the CNC plasma table.



The plasma leaves a bit of a rough edge, which Brad cleaned up with a belt sander and some other tools. Austin (above right) added a brushed finish to the main surfaces with the burnishing tool, too.



Brad cut slots in the C-pillar / rear glass surround, and our aluminum chassis mounts slid down into place and bolted to the chassis along several points. Then the outer wing uprights were mocked up (above right) to these chassis plates, then marked, drilled, and bolted together. This way we didn't have to fish a giant piece of aluminum down into the chassis. If we needed to run an event in a class without aero rules, or if we wanted to change the wing placement with a new set of external uprights, the chassis side pieces could stay in place. This proved to be a smart move.



We made some changes until we were happy with the stiffness of the wing structure, added 272 pounds of ballast to the carbon wing (I wasn't too fond of standing on the wing, but this more than covers my weight), and then it was time to modify the rear Lexan for clearance.



With a slot cut away to allow for the chassis side brackets that sit just above the rear glass, the Lexan was reinstalled and the final wing assembly was complete. People doubted we knew what we were doing, and I even heard from someone at Ford (they had multiple wing upright failures on the GT3 Mustang), but our setup is super strong and has been on the car for almost a year as I write this with zero issues, no wobble, and no deflection on track.

BLOCK ALL OPEN GRILLS NOT BEING USED

Anyone who looked closely at this Anderson Type ST "GT500" styled front end would see some VERY large grill openings that didn't do anything but add places for air to get trapped underhood.




Brad discussed this with Jason and me, and we agreed that now would be a great time to start blocking off these openings. The outer two lower grills were especially large and just asking to be blocked off. Brad started with a cardboard template...



That was transferred to some ABS plastic sheet, which he safety wired in place. Sounds sketchy, but it lasted for 6+ months like this, and we even added more block off plates to some unused portions of the upper and lower center grills at a later time with the same attachment. Less high pressure air getting underhood to cause lift is always good.

VERSION 1 OF AERO: COMPLETE!

After a couple of weeks of work, several tweaks to the uprights, a lot of time spent on the splitter, and the blocked off front grill openings it was time to show the first version of aero on Trigger, September 7, 2023. We were loading up on that Thursday for a track test the next day, which I will detail below.



Now this aero package would change several more times over the next few months but the basics are still there - the 9Lives Racing dual element wing, the Professional Awesome splitter struts and tunnels. We would later change the placement of the wing, moving it down and forward, but I will show that in a later installment on this forum thread.

TRACK TEST 3, SEPTEMBER 8, 2023 (FAIL)

We had high hopes that we had solved the oiling issues with the line size bump and Accusump, but even if it wasn't totally "Fixed" maybe we could still get 1-2 laps in without triggering the low pressure engine retard. The hope was that the added aero would add enough downforce to still drop lap times significantly. I made some key mistakes here...



I trailered the car out to MSR Cresson on a member day without anyone to help or shoot pics, and that was my first tactical error. See, whenever you make MAJOR aero changes to a car you should have someone there to look for and hopefully capture the look of the car with pictures and/or external video. I could feel things behind the wheel, for sure, but I had no spotter to tell me if the car had front end lift (it did), rear suspension squat (it very much did), or anything along those lines.



Above is in-car video on the new fast lap in Trigger, a 1:18.716. This technically was 2 tenths quicker than the previous best / winning time I ran without aero in August (1:18.933) at the last SCCA TT, but the car was such a hot mess. The low oil pressure started triggering happened right away, then when I armed the Accusump it dumped in the first corner and never worked again. The aero made the issue worse.



My best lap was in the first session when it was 81F, where I made 3 lap attempts and didn't get clear track and a good drive until lap 3. I went out twice again in the next session about an hour later but it was already 86F and climbing. Low oil pressure issues all day. I was really hoping that changes to the Accusump - only arming it after the first hot lap and now seeing a light when it was "triggering" - would help. The Accusump would indeed "dump" when it saw less than 37 psi, then it worked for one corner. The problem was the Accusump could not recharge until my cool down lap. So it was a "single shot" fix, and was not going to solve our issues. A dead end.



Who would have thought that adding more lateral grip with the downforce made the issue worse than before?!? (duh) Adding aero was a great upgrade, just done in the wrong order. A buddy showed up and he shot ONE picture of the car, above right, but apparently he had never worked a digital camera before and that's what we got, above. (facepalm)

When I left the track I was hot, tired, and just utterly disgusted. I was frustrated that we had burned the previous 2 weeks building the splitter and wing mounts and not actually addressed the real problem - we needed to move to an external dry sump oiling system. We had 5 weeks until the next big event we were scheduled to run in this car, on this same MSR 1.7 CCW course. I worried that THIS was the end of our 2023 season with the car, and that we didn't have time to resolve this.



When I left the track, the temp gauge on my F350 showed 119F degrees, and on the way back to the shop I had the first blowout on the trailer that I've had in ages (I would get another a month later). Old tires and high temps just combined to make my day "extra fun".

ADDING AN EXTERNAL DRY SUMP OIL PUMP

That heading above sounds so simple - just add an external dry sump pump! But no, don't believe the videos and con men - adding a dry sump oiling system is a LOT of work. This is not a decision that anyone should take lightly. We ran our narrow body C6 LS2 car with a wet sump (with an Improved Racing baffle) successfully for 2 seasons on the EXACT same 315mm A052 tires, and had none of these issues.

The LS7 based "dry sump" system is just generally considered SO BAD that it can indeed be worse than the GM wet sump oiling systems - as we have seen. Yes, I said that - the LS7 "dry sump" is worse than many wet sump systems, especially the earliest C6 Z06 cars with smaller dry sump tanks. We had a huge 3 gallon tank, and it still didn't work.



This conversion to an external dry sump pump and new pan involved many thousands of dollars in parts, lots of phone calls to HPR and ARE, way too much custom machining, and many hours of plumbing and fiddly work. We gobbled up all 5 weeks of time we had until our next event, getting all of this built and dialed in. So now let's cover how we solved the low oil pressure problem, and look closer at why the OEM LS7 dry sump parts just could never work on this setup.

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Project TRIGGER Update for August 20, 2024: It's been 8 months since the last update to the TRIGGER portion of this thread, which is our shop's S550 Mustang LS swap test mule and time trial competition vehicle. This car did a lot more events through 2023 and we made a lot of BIG changes during the 2023 season.



On my last update back in January we left off on work and events completed in August 2023. We were still fighting low oil pressure situation that triggered below 30 psi when the engine was above 3000 rpm. I was pretty flustered, and while the time period we covered last time started out fairly positive it ended fairly negative. Well good news - this time we start off with a hot mess of a car, then we make some key changes, and by the end of this time period we taste the sweet smell of victory!



The improvements this time started off a backwards order - we first added front and rear aero treatments, tested with that and the LS7 dry sump + oil line size increases, THEN we finally tackled the 800 pound Gorilla by adding a proper external dry sump system. So let's jump into to this round of updates and see the performance increases each time out. We also replaced the Holley EFI and added a proper AiM digital dash, and now we even have proper data logged videos.

PHASE 2: LET'S ADD AERO?

This was one of our best ideas for this project, as adding downforce almost always drops laps time. But the timing makes no sense, and as you will see below this barely nudged lap times down, because the oil pressure issues got SO much worse. The plywood front splitter on Trigger was a departure for us, as most of our former front splitter elements were made from aluminum.



We built splitters out of aluminum for a decade, but after a particularly costly (to me, as I ate a ton of the fab hours) multi-layer aluminum splitter on this S197 Mustang above, we decided to look at other splitter material options.



I am proud of the aluminum splitters we have built on numerous cars in the past, but the cost of 3/16" aluminum sheet went NUTS during the pandemic and didn't come back down - plywood is 1/10th as much!



We had just built a plywood splitter for this customer's CTS-V (above) during 2022, and it ended up lighter, less costly, and less time consuming to build than our previous aluminum versions. We did this with a $45 piece of 1/2" thick plywood as a test - but have since moved splitters to denser / better plywood.

This one worked so well on track in 2023 that we decided to go with a plywood splitter for Trigger. And while that might not make sense to everyone, we all have budgets. I also knew we'd probably need to make 2 or more splitters for this car for the different classes we wanted to run it in. Anyway, let's start out with the front splitter and then we will cover the massive rear wing.

FRONT SPLITTER CONSTRUCTION

I am showing a lot of detail in this section as this will likely become the basis for a "how to" splitter article elsewhere in this forum. We had used plywood in the past but I felt that the aluminum units had a weight penalty. On this project, which has already exceeded my minimum weight plans considerably, we needed to keep weight down. So after conferring with Jason here in Engineering and some outside aero specialists like Mike at Professional Awesome and Johnny at 9 Lives Racing, we decided to go with 1/2" MDO plywood.



Jason knew about this specialty plywood supplier that had a huge indoor warehouse in Ft. Worth called Ft Worth Plywood Company (well, the name is descriptive!) I went by there with my F350 not really know exactly which of the half dozen options we saw on their website was the right choice. I asked up front and they sent me to their most experienced shop foreman and he knew what a splitter was, so that was a plus. We walked around and looked at several options but he suggested this fully primed 1/2" thick MDO plywood, which was about $114 per 4x8' sheet. We had a number of splitters we were planning to do so I paid and left with these 3 sheets.



Back at the shop Brad started by stringing the car along the front axle centerline (the furthest back we can go with the splitter), the front fender opening, and another string down the center of the car. We then measured the "outer track width" up front then measured what the enclosed trailer would fit.



The rules in question (above left, click to see higher rez) changed at the end of the 2023 season, but we built to the "new" rules because we used the (at the time legal) alternative classing rules for CAM-C from SCCA Solo for the forward 6" extension. But there was no allowance to make the splitter wider than the car (it simply isn't mentioned) so we kept the width the same as the maximum track width we had. We only had about a 4" width gap from the tires to the fenders in the trailer to work with without having to remove the splitter to load the car (which matters to me), so it wasn't a big loss there.



Now that we had the envelop to work in, Brad could start on a new template from 1/8" press board. This stuff is cheap (less than $20 for a 4x8' sheet) and rigid enough to work with for transferring the final shape to the plywood. If we messed up here it was $20 worth of material, not $114 worth of MDO. We started with one of our existing S197 templates to get the rough shape of the wheel openings (track S197 and S550 widths are very similar) and he cut out the front tire openings so we could get a good look at the front.



The SCCA Time Trial Max 1 rules (2024) and CAM-C rules (from 2023) limits the rear edge to the front axle centerline (common rule) and the front edge to 6" beyond the bodywork. Now we have legal aftermarket bodywork on this car, and this Anderson GT500 nose has a little splitter lip that is included and attaches to the nose, and its all fiberglass I could have argued that this WAS the front bodywork, but the peanut gallery was squealing while we were showing our work. So I took the hit and Brad modified his magic 6" stick to have a notch in it at the rear, so it could follow the "bumper cover" and not the add-on splitter lip piece.



We used many of the tricks we utilized in the past to get this template perfected. More time spent on the template means less mistakes or time wasted on the final part. Brad and I worked with Jason until we were happy with the final shape, and I ran it by the rules makers to get approval.



The SCCA TT folks got a BIG letter from me about this and some other "alternative ruleset" issues. They weren't happy about the CAM aero rules we were using for 2023 but they allowed it, as it was in the rule book. For 2024 they changed the Max aero rules in TT to match the CAM rules, then divorced the rule sets. It was a fair concession.



One of the SCCA TT Max rules I had an issue with respect to the allowed splitter tunnels - the surface area they had in the old rules didn't even meet the OEM installed tunnels in undertrays for a 2016 GT350 - which had 2x the surface area Max allowed! I sent many pictures with measurements to back up my case, and it was one of the things that pushed them to update the aero rules. So for 2023 I ran the (allowed at the time) alternate CAM-C aero rules, which had NO limit on splitter tunnels - and ran two of these giant Professional Awesome units.


The image above is a second splitter with a 12" front extension that we made for NASA TT1 class use in early 2024

Sorry that section got a bit wordy but I wanted to explain what DRIVES our design of a front splitter - the RULES. We always want to maximize the size of a front splitter: forward, rearward, and laterally. And also run the biggest tunnels we can fit in there. Why? Because you can NEVER MAKE TOO MUCH FRONT DOWNFORCE.



We still wanted to be able to get this splitter off quickly, if we needed to work on the car at the track. We looked at multiple options for a rear mount quick release setup (all of which get very complicated when you actually go to build and use them - lots of experience with these) but settled on this slip in bracket for the rear edge.



I didn't like how little of the rear splitter surface area the bracket could hold, and the previous mount was too low. We scrubbed that and made a much bigger panel that held the splitter over about 6" forward of the trailing edge (vs 1" before). This required a few semi-circles to be cut into the splitter to tuck up into a flat recess of the front crossmember.



A week later we came back and added more holes to mount this to the subframe, with some guide fences for the sides. The extra holes make the bracket / panel more rigid, and the side fences make it easier to slide the splitter into this pocket.



With the rear mount completed using the press board template, Brad traced that onto the MDO plywood and we got to work on making the front mounts and setting the height. We had actually settled on a 3.5" front ground clearance, which happened to line up with the bottom of this GT500 nose - so we needed no air dam this time. We tested this height with our Race Ramps and it cleared, barely (below).



We tripled checked and the splitter was level with the chassis, but we planned to run some rake on the ride heights to make the front edge dip down for a more aggressive splitter angle. Again, we were trying to work with this front nose, which we thought we'd keep for a good long time (we only kept it on for about 4 months).



When it comes to exposed splitter struts, we have used numerous brands and types. We have been moving all of our splitters to these carbon graphite rod versions from Professional Awesome and really like how they perform - they are rigid in tension but can buckle in compression and not sustain damage for a light "off". If they are damaged, it is easy and inexpensive to replace the rod and reuse all the ends. The image above shows the rough layout where we had four of these units planned. Two would go inside the grill and two would land on our custom tubular front bumper beam - this aspect was planned LONG ago.



The two "inner" rods lined up well with these mounting points on the front frame rails, where our bumper beam bolted on. Brad was able to simply bolt the upper mounting flanges to these exposed bolt threads with another nut. Then he passed the carbon rod through the grill (just opening up one "cell") and down to the splitter plane and the "pretty" lower mount.



For the two outboard mounts we needed to make some steel weld bungs that were threaded for the upper strut mount. We used some 1" dia steel we have in stock and whittled these short bungs on the lathe. Then Brad sculpted the back side to match the 1.75" OD tubing from our bumper beam.



We lined those up, tack welded them in place and checked our alignment. Then Austin TIG welded those to the beam in place. Once that cooled Brad ran an M8 tap down into the bare hole that was machined on the lathe. We could have tapped these on the lathe but this was quicker.



Brad then masked off the tubing and painted it gray after the welding was complete, then made a short length of M8 threaded stud (cut the head off a bolt). This was then secured in the upper strut mount with Red Loctite, then threaded that into the bumper beam.



With the upper and lower anchors in place the graphite rod was cut to length and secured between the two compression fittings. The two inner mounts had some Professional Awesome titanium skid blocks added to the lower mounting bolts. These are sacrificial pucks and should wear before the splitter ever takes any damage. Plus, they make sparks!



At this point we had a nice splitter, built to the max limits of SCCA Time Trial Max rules. Many would stop here, but we wanted more downforce than a flat splitter would provide, so it was time to tackle the next step - tunnels. If designed and placed properly these will create more downforce and could redirect some air for other uses - like front brake cooling.

ADDING TUNNELS TO THE SPLITTER

Brad used a router to smooth the leading edge of the splitter, and the top edge as well. In hindsight we could have used a much more aggressive radius on the lower edge. With that complete it was time to lay out the PLACEMENT of the Professional Awesome Large splitter ramps. These are plastic tunnels that are very large and we had to weigh a lot of variables to find the best location and orientation of them both.



We reinstalled the lateral string at the trailing edge of the front fender openings, then looked at the placement of our fender liner openings - which normally would line up with the factory 2018-23 Mustang GT PP2 lower undertray tunnels. We wanted to utilize the airflow from the ProA tunnels to feed our brake cooling, too.



These ProA units are about 5x bigger (projected surface area) compared to the factory PP2 tunnels, so we had to test fit the new units several times to make sure they fit within the space from the front bumper cover to the fender openings (just barely).

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[Fair!]

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At this point I had put 16 liters of oil in the 3 gallon dry sump oil tank, adding another liter today. Still could not fathom how it could run out of oil in a corner with this much oil in the tank. Coolant temps were fine all day (195F) but at this point we still cannot see oil temps on the craptastic Holley dash - only if we connect to the ECU via a lap top to "look at the data" afterwards, which is still a jumbled mess. Handling and brakes worked great.





In Sessions 3 and 4 I made my first hot lap, got a good time, took a cool down, and came into the Hot Pits. And sat there in the car looking at live timing on Race Hero, watching my main competitor Stan's lap times in real time. After a few minutes of seeing everyone's times dropping off due to tire heat, I'd fire up the engine and drive back into paddock. This way if I needed to go out and maybe hunt for a tenth of a second, I was ready and right there. Good strategy.



At the end of the day the SCCA TT group had a trophy ceremony - the first in this Region's history for a Time Trial. The "gold medal" for first was cheesy but still appreciated. Gave people an excuse to stick around and drink a frosty beverage before rolling out.




Amy drove her '23 BRZ to 3rd place in T3, only .03 out of 2nd and 0.4 sec out of the lead. Vorshlag tester Jon Miller won T3 in his BRZ, and I took the win in M1 class, which was a first for this car. We all went to Braum's for ice cream afterwards - winners get sprinkles!

LAST OF OUR POINTLESS OIL SYSTEM FIXES WITH LS7 BASED DRY SUMP

After this mid august SCCA Time Trial we had a TWO MONTH break before the next SCCA event in mid October. This gave us time to test one more round of Band Aids to the LS7 dry sump system. This was the last hurrah before I threw in the towel and bought an external dry sump system.



Again, after ever track event we check the oil catch can, and Brad found a little fluid in there this time but not much. Where the heck does that 16 liters of Motul go? Well it sits in the tank, and some in the engine and some in the cooler... but not enough in the bottom of the pan on long left handers!



This Accusump addition has fixed low oil pressure situations in wet sump LS engines for us before, and this 3 quart system is huge. It is the same unit we had in Trigger for a while with the LS6 engine, but that engine was not long for this earth. So it needed to be completely discharged of pressure, disassembled, and thoroughly cleaned.



Luckily Brad kept the brackets he made for this monster sized Accusump and it went right back in with a 37 psi sensor - so it will dump if oil pressure gets under 37 psi. Seems a tick high, but we will see if it works...



The last thing that was theorized as a potential oil flow restriction was the main -12 AN hose that went from the external Petersen 3 gallon dry sump oil settling tank to the "suction" side of the LS7 oil pan. So about $230 worth of lines, fittings, and hose ends were ordered to up-size this to a -16 AN hose as well as re-routing it for a shorter run.



This plumbing trick usually reduces oil pressure loss across long hose runs - even with a -12 size at the pan, the larger -16 hose will reduce pressure drop / improve suction from the LS7 oil pump pressure pump. As we would find out at the next track test NONE OF THIS HELPED OUR SITUATION.



This is when we sent the two Holley dash units off to the 5th tuner to try to have him update the firmware so they would communicate properly with the ECU and we could finally modify the screens and get the GPS sensor to work, which would be a huge improvement for this Holley system. After 3 weeks of trying he gave up and shipped them back. We also sent two oil samples from the HPR 454" engine to Lake Speed Jr's company for analysis (all good).

LAP TIME COMPARISON

For a quick reference of "where we're at" we always like to list lap times with video links for the car in the forum post plus a few others to compare to at our Motorsport Ranch Cresson 1.7 mile, CCW test track. I have 800+ laps over ~24 years at this track, and drove all of these laps listed below at this track / configuration, with either AMB transponder or AiM Solo lap times. The cars in this list include our NASA TT3 prepped 2018 GT, 2024 Darkhorse, and of course the star of this entry, our 2015 Mustang #Trigger - all 3 tests on the MSR 1.7 CCW from this post are in bold. Just know that we have gone significantly faster than this as I write this, but I'm only listing what we have covered so far.

MSR-C 1.7 mile CCW:

• 1:31.619 - 2024 "Brembo" Mustang GT, 255mm 300TW tires, bone stock, Track Test #1
• 1:20.348 - 2018 Mustang GT, NASA TT3 prep, 305mm RE71R, MCS RR2, 474 whp (fastest this car every ran on 200TW)
• 1:20.677 - 2024 Darkhorse baseline stock, 180TW Trofeo RS tires, Track Test #1
• 1:18.417 - 2024 Darkhorse, -3.5 deg camber with SPL arms + Vorshlag plates, 180TW Trofeo RS tires, Track Test #3
• 1:28.064 - 2015 Mustang #Trigger, first test laps 6/29/23, 627 whp, 5 year old 305mm Bridgestone 200TW (junk!), Track Test #1
• 1:18.878 - 2015 Mustang #Trigger, testing 7/22/23, 200TW tires 315mm A052, 627 whp BTR Trinity + 112mm TB, Track Test #2
• 1:18.933 - 2015 Mustang #Trigger, 620 whp, no aero, MSD Atomic, 200TW tires 315mm A052, SCCA TT 8/12/23

WHAT'S NEXT?

Of course I didn't get as far as I would have liked, but at 5 parts and 20K words, it's time to wind it down for today. Here's just a brief glimpse of what we will cover on this project next time.



We tackled some major mods in late August, including a big front and rear aero package. And guess what? It made the oil pressure situation MUCH worse! After that we added this A.R.E. 4 stage dry sump system, and DUH that was the answer! Then we focused on making the now ultra reliable package even faster, upgrade from the Holley to a Haltech EFI, and more. We will delve into all of these upgrades, and cover more track tests and Time Trial wins, next time.

Thanks for reading!

Terry @ Vorshlag