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Unread 01-26-2015, 12:17 PM
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Fair! Fair! is offline
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Join Date: Jul 2004
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Default Re: Vorshlag Budget TT Build: Project DANGER ZONE

continued from above

The other TTC cars included BJ Mayer's 2003 Mini Cooper S, from Clown Shoe Motorsports, above. This was his beefed, up daily driven, TTC car's debut. It has a better power to weight ratio due to the 205mm tire he runs (>245mm tire = +0.8 ) as well as it being FWD (+1.0), for an unadjusted ratio of (12.0 - 0.8 - 1.0) of 10.2:1 pounds per whp. This car had GAZ coilovers, Vorshlag camber plates, a header/exhaust, supercharger and engine engine mods to help it make more power. I think his race weight was 2550 pounds or so? He told me but I forgot. He was on the SpecMiata tire, which is a 205mm "SM7" Hoosier (essentially an R7).

The TTC regular for the Texas Region was Herberto Ferrer in his 2005 RX8. This car is pretty well prepped and he runs the Hankook R-compound race tire, but I am unsure of the rest of his mods. This is a dedicated race car, though, and he is at almost all of the NASA Texas events running TTC. We also had Bryan Leinart who brought his CMC 4th gen Camaro into TTC for two sessions (Warm up and TT session 1) on Saturday and Sunday.

The ugly side of the Corvette. We're working on it.

I took my first two laps pretty easy in the TT Warm-up and tried to follow Allan, as planned. I was still feeling out the car, shift points, brakes, and tires when I botched a downshift going from 5th to 4th into the Courusel, T2, on hot lap 2. Instead of grabbing 4th as I had hoped it went into 6th, but I didn't realize that for a few hundred yards. The motor made all sorts of grumbling noises and had ZERO power. I coasted for about 400 yards around the long 270 corner dubbed the Carousel (Turn 1) and even past the start finish line. I had seen a 1:49 on predictive timing flash by on that lap, but with the long period of coasting it made for only a 1:50.692 lap. I finally figured out what happened by T17, downshifted into 3rd and set-up for another hot lap. Then I caught the back of the field pretty quickly and started smelling some oil smoke, so I came in early.

What I had found when I went into 6th was what the engine tuner warned me about - there's a massive dead spot in the engine between 2000-2200 rpms. Nothing happens - it makes no power. This makes the car drive poorly at these low RPMs, as when you hit 2000 it wants to die. So I made a note to keep the revs above that range, even on the warm-up and cool down laps, and it didn't happen again all weekend. Kind of freaked me out when it happened, though. "Old car stuff"... probably a worn out sensor or something, but the 1992-only engine computer is really limited and hard to diagnose issues with.

Once I came in I went back to my paddock spot and Matteucci and I looked at the smoking issue. Just as he had warned me it was the rear main seal leaking. He had already replaced the RMS once, so I figured it had to be something else. After power washing the bottom of the car to clean all the oil residue off, it never leaked another drop when idling at the shop... but after a few hot laps on track it was clearly a leaking RMS. After we let the car cool for 20 minutes with the hood up we moved the car to get it in the air, and the oil spot (see above) was the extent of the puddle. Not much, about the size of my hand, but every drop that leaks out while driving on course hits the exhaust 4 inches away and made for a SMOKE screen. Luckily this only started after two hot laps.

Times from TT Warm-up - I was in 4th out of 4 in TTC!

I thought we would be sitting up front of the class, even with the 1:50 time, but that was wrong - I was in LAST PLACE out of 4, ouch! I quickly got some text messages from people who weren't at the event asking me why I was so slow, hehe. It's easy to armchair quarterback something when you are hundreds of miles away. The fastest TTC car was the CMC Camaro (1:48.069), followed by BJ's Mini (1:49.768 lap), then Herberto's RX8 (1:50.324) then my coasting time of 1:50.692 bringing up the rear. I suspect my first session times may have lulled some folks into thinking we'd be eating dust all day, but I honestly wasn't worried. Much.

So Matteucci and I got the car in the air on two jack stands and I crawled underneath to clean off the accumulation of engine oil, which wasn't much. A bit of brake parts cleaning and some blue shop paper towel and it was spotless underneath after 5 minutes. It wouldn't drip once the engine cooled off, but this was also wasn't something we could properly fix track side. The RMS repair would require removing the transmission, clutch and flywheel back at the shop. Once all that is out we could then assess the issue and probably install a "seal saver kit" for what is likely a ring scored around the back of the crank.

We went over the rest of the car and it all looked great - including tire wear (perfect) and oil level (still totally full). Brakes felt a little spongy but not enough to bleed yet. Warm tire pressures were 34-35 psi, which is right where the Hoosier A7/R7 "Tire Care Tips" article said to shoot for. After I noted that I had a bit of syncho "snick" going onto 5th gear, Brian adjusted the clutch pedal travel stop that he built, moving it a hair to allow for more clutch dis-engagement. These 3-plate clutches are tricky to set-up and a bit of a chore in the pits... I stalled it a few times until I got the hang of it. The release range is VERY narrow and with almost no flywheel mass the motor has less momentum - making it easy to stall at low speeds. But once at speed? Oh, yea it was worth it! You actually have to shift pretty quickly to allow the revs to match, otherwise the engine slows down too much and lurches even on upshifts.

After checking multiple times that day the NASA scales were still not operational and we were told they would be down for the rest of the day. Knowing that we could have pulled all the ballast out but that would have been a douche move, so we left it all in and even topped the fuel tank off after each session, to keep the tank full and to count on the 120 pounds of fuel ballast. Limiting our runs to 2 hot laps, plus the out- and in-laps, the car was using 1.5 gallons of 93 octane gasoline per session. This was good to know since we were using extra fuel as ballast. I always wanted to be ready if the scales suddenly became operational - weighing under your declared minimum weight (3203) will DSQ the times from the session you just ran, as does a 4-wheel off or spin on course.

Matteucci was signed off for his TT license, since he had extensive SCCA club racing experience. Our "tactical plan" at the start of the day was that I would drive the first two sessions and he would drive the last two. But with the oil leak he declined to drive at all, and I changed my own plans to only take one or two hot laps per session, thereafter. The weather during the warm-up session was cold and I knew the track would get quicker once the sun beat down on the asphalt a bit, so I got geared up for the second TT session of the day, "TT Session 1", which I had hoped would also be my last for Saturday.

Just part of the 32 car Saturday TT grid, lined up for session 2

I was 12th on grid, right behind BJ's Mini, and was anxious to knock out a better lap. I still felt that the 1:46 lap I predicted was possible, I just needed to put it together and avoid any mistakes. I left a pretty big gap to BJ on the out-lap and didn't do any tire scrubbing. The R7s don't need any warming on this car, and they just work. I really REALLY like this compound and I am glad we made this choice. They wear well and grip was well past 1.2g lateral, in the data logging. Dyson Pham had something like 22 heat cycles on his R7s and still won TT3 on Sunday.

Went out and the first lap was a 1:47 and gobbling up the gap to BJ pretty hard. I went ahead and took a second hot lap and finally nailed the speed into and out of the big Carousel, which plays a big part in any lap at MSR-H. The speedo was showing 110 mph at the "Launch" (T13-14), 119 mph entering T6 on the back straight, and 113 mph entering the Carousel (T2) and 86 mph though that crucial turn. When I saw the AiM SOLO show my second lap at a 1:44.956 I knew that had reset the old lap record by nearly 6 seconds, so I took a cool down and came in.... with the biggest smile on my face in months.

Saturday TT Results:

After seeing the times from that session I noted that our car was the 7th quickest TT car out of 32 entrants so far. But then I noticed we only had 4 in class, so I went looking for a TT driver and instructor who hadn't run TT yet that day. Once you declare a class you have to stay there for the rest of the day. An old college friend Chris Ramey had been having fun in his TT1 Corvette on street tires, running in HPDE4 that morning, and jumped at the chance to take a ride into the #DANGERZONE! Ramey owns 4 Corvettes at the moment, including a C6 Z06, a C5 Z06, an '87 Z51 C4 and a Callaway Twin Turbo C4. Our TTC prepped C4 would be one of the slowest cars he had driven in a while, heh.

After getting the car reset to drive (jack up, clean oil, etc) and adding his registration as 192 TTC, attaching my second (battery powered) AMB transponder to the car and switched off the primary AMB, we had our 5th unique TTC entry. He strapped into the car and asked me what the target lap was. I knew Chris would be fast, and he has a tendency to go "Faster than you'd expect" so I told him to run a 1:46 lap. And asked him to only take one lap, due to the smoke. He got to grid for the 3rd TT session of the day and promptly put in a 1:46.165 time on his first and only lap, watching the AiM SOLO predictive timer closely. Normally I'd have told him to go for broke but he wasn't signed up with Hoosier contingency and I was, so we held him back... Chris told me he felt a 1:43 was possible. Yikes!

End of day Saturday TT Results - #DANGERZONE takes P1 and P2!

The rest of the TTC class didn't get much faster and the sun went behind the clouds right after that session, which cooled the track down. I felt fairly confident that the times would slow down in the 4th session and we sat out the last chance to put in a lap that day. That always makes me nervous but the cooler temps did indeed slow everyone down and my one timed hot lap for the day was enough to win the class, and Ramey's handicapped lap was still good enough for 2nd. BJ and Herberto got quicker after the Warm-Up and beat the fastest entry from that session, the CMC Camaro of Leinart, and every single TTC entry that day clobbered the old class track record.

The TTC win with 5 entries netted us 2 tires from Hoosier and 100 points for the regional championship. The Mini's time was still pretty close to Ramey's but about 1.4 seconds back from my time, so we were definitely keeping an eye on the Mini and the RX8 for Sunday. Anything could happen tomorrow, which was a whole new race.

After Ramey's lap was done we got the car cooled off, up on jack stands, cleaned up the oil residue again, then bled the brakes (in the strange order you are supposed to on a C4) with some RBF600 and rotated the tires. We didn't need to do that last bit, but it didn't hurt and took no extra work. Chris had complained of a long brake pedal and he was right - the pedal felt like mush. Bleeding it didn't help much so it was something we'd have to keep an eye on all weekend and address back at the shop. The fluid looked perfect and the 4 corner bleed produced zero bubbles. Hmm. Matteucci found some RTV and pookie'd up the bottom of the bellhousing, hopefully slowing down the smoke - he was covered in black RTV when he was done, though.

Left: The smoke looked like this after 2 laps, time to come in or risk a black flag. Right: Sunset Saturday at MSR-H

Very happy with the first result considering how little we did to the car. The tire wear was phenomenal even with only -2 front/-2.5 rear camber. Toe was 1/8" out up front and 1/8" toe in rear - Matteucci had strung the car himself and we left the alignment alone. The 34-35 psi pressures worked perfectly. The car was neutral if a bit loose, which is just how I like it. The brakes were far from perfect but replacing the 24 year old rubber brake lines might make a huge improvement, as would some real brake cooling (there just wasn't time).

The regular Saturday NASA party was great, with excellent bar-b-q and beer, trophies for the class winners, and pictures for the NASA newsletter. Dozens of people asked about the build and were amazed at the 1:44 lap time,and we had dozens more stop by the paddock both days wanting to see the car and admitting that they followed this build thread. After we had our fill of food we went back to the VERY dark paddock to load the car in the trailer... the trailer door was blocked. Hmm, car has no windows and I couldn't find anyone. After we left I texted Paul Costas and he added a blanket to the car to keep moisture/dew out - which we dubbed his "woobie". It looked hilarious the next morning, for sure.

Sunday January 18th, 2015 - Race Day 2

Costas' woobie kept project #DANGERZONE warm and dry, hehehe

Matteucci was going to work on his C5 Z06 all day so I was on my own for Sunday, but Jaaon Toth planned to help me with the car in the paddock, plus he took a bunch of pics with my camera. I got to the track by 7:30 am, had tons of time, so I ran down to Buc-cee's and got breakfast burritos for everyone in our paddock area, a giant bag of ice for the coolers and filled up the F-350 with diesel. Was back by 8 am with the first session scheduled for 8:50 am.

Left: TT3 racer Joshua Garcia brought his Toyota 1UZ V8 swapped AE86 and had a blast. Right: An E46 330Ci which used to be mine

Figuring the first session would be cold again, and still needing an extra TTC entry, I asked TT driver/instructor Jason Toth to take the first session in the Corvette as TTC 192. Since Sunday and Saturday are separate races, using the same number as Ramey did the day before isn't a conflict. We strapped the extra transponder back on and he got to grid for the chilly first session. I was again hoping the same cars from Saturday would enter and give us five in TTC so the winner would get two tires, whoever that might be.

continued below

Last edited by Fair!; 01-26-2015 at 12:32 PM.
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