Recap of my first weekend out in the new TTA Z06

[Cobra4B]

For those interested in the build there is a seperate thread in this forum. Basically I scooped up a higher mileage (119,xxx) 2001 Z06 a couple of months ago and set about turning it into a TTA car with intentions to cage it this winter to make it PTA/ST2 legal. I ran VIR full course with Mazdadrivers this past weekend to shakedown the car.

Basically I turned this...




Into this...





The car weighed in at 2840 lbs with a 1/2 tank of fuel and heavier street wheels/tires on the car. It made 361 rwhp after being dynotuned at Virginia Speed. I am running front 2001 OEM Z06 wheels all around. They are 17x9.5 forged aluminum units manufactured by Alcoa. A little Corvette trivia... the 2002-2004 Z06 wheels are spuncast and manufactured by Speedline. They are 1lb lighter per wheel than the forged Alcoas, but are not as strong. For tires I'm running a 275/40/17 Hoosier R6 all around.

The car is running slight toe-out in the front with approximately 2.5 degrees of negative camber and slight toe-in and around 1.5 degrees of negative camber in the rear. The cross-weights came in at 50.3% with 215lbs of ballast in the driver's seat without any extra adjustment.

My graphics came in a bit late, but they showed up Thursday the 26th so I was able to get the car finished up that evening and ready to go to the track on Friday. All loaded up and ready to roll...


Got to VIR Friday evening a little after 6pm without issue. Got the car teched and unloaded. Here's some paddock area shots. My buddy Ryan was there to test his new aero on his ST2 C5. It's nice to have friends with 28' air conditioned trailers




Gridded up for Saturday morning's first session. They had to cancel the instructor's session due to a fog delay. We had heavy fog both mornings. It caused more of a delay Saturday than it did Sunday.



Looks rainy, but it wasn't... just the lingering fog that went away shortly after these pics were taken.






The first session was interesting. My last time on track was in July with the GRM UTCC in my father's Panoz... we had nothing but issues culminating in a snapped crankshaft and ruined motor. This previous experience plus having a "brand new" car on track lead to lots of gauge watching and getting a feel for the car. The car performed flawlessly from a mechanical standpoint; everything worked properly. The oil temp wouldn't get out of the low 230s in the cooler morning temps. The high volume oil pump pushing 10w40 Amosil kept the oil pressure gauge pegged at 80, but eventually it came into the high 70s.

Once I was convinced the motor wasn't going to blow up, and that the clutch, transmission, and brakes were performing properly on track, I began to speed up and get a feel for the car. Compared to the Panoz I loved the firmer steering feel of the C5. The Panoz is overboosted and has a dead spot in the middle. It works, but you have to get used to it. In addition to the steering the overall ergonomics were wonderful. Being 6'4" 230 normally I have a hard time fitting in a car correctly. For this car I had a custom Ultrashield made and fitted everything exactly for me (no car sharing compromises). For the first time in my life everything was in the right position. This allowed me to really focus on driving vs. dealing with poor body positioning.

The car is very very quick. 361 rwhp in a 2800lb car will do that. I could instantly feel the benefit of running the super light 17x9.5 Z06 wheel/275 tire combination. The car would pull like no other stockish C5 Corvette I've driven. The car is probably quicker than my old yellow 2001 Z06 that was cam'd making 436 rwhp.

That quickness was offset by a lack of traction. The 275s and lack of any aero required a careful application of the throttle everywhere on track. There was a good bit of drifting and sliding in the first session. Other TTA drivers had warned me that driving on 275s was a bit like ice skating at times and would take some time to get the feel of the car. The other place the car felt entirely deficient vs. the Panoz was the uphill esses. The Panoz is 2700lbs and has basic aero. As a result I can go pretty much flat out through the esses and have no issues with the hump on the first rt had turn. With the Corvette that hump wanted to throw the back end of the car out to the left. After a few laps I got the feel for it and adjusted my line to take that section on a more direct line to keep the rear end planted.

Brakes felt fine, but drastically different than the manual brakes in the Panoz with PFC97 endurance racing pads and PFC floating rotors. On the Z06 I'm running DBA 2-piece front rotors up front and stock in the rear. Pads are Carbotech XP12s up front and XP10s rear with Stoptech SS lines and DRM cooling ducts with ECS spindle ducts. The power brakes felt numb vs. the manual ones, but they stopped the car fine. The equipment performed flawlessly and the brakes worked without issue.

A few shots from later in the day when the sun was out.







The 2nd session on Saturday was much improved over the first. The track had some heat on it and the car was much more planted around course. The "ice skating" wasn't nearly as bad as I thought it would be based on the first session. The car puts the power down pretty good on the 275/17s. I couldn't keep up with Ryan's ST2 car (He's on 315 A6s w/ full aero), but I found that I was very evenly matched with the driver in the Orange GT3 RS Porsche. We had a great time playing lead/follow and pushing each other.

Traqmate showed a max speed of 147 on the back straight, but I was short shifting the car just over 6000rpms. Based on how the car accelerates I believe the car would pull 155ish with a proper run out of Oak Tree and redline shifts. My best lap time was only a 2:11.06 in traffic with a TBL of 2:10.xx. I was hoping for better seeing as I have run high 2:06s in the Panoz and generally run 2:08-2:09s in traffic. The Z06 felt much quicker, but the lap times weren't showing it.

A comparison of the Panoz data to Z06 data showed the Panoz gained it's ground in turn 1 through turn 5, the uphill esses, and the sweeping left-hander after the esses. My feeling is that it all comes down to the car's aero and power delivery. I can go flat out coming out of 2 and through 3 in the Panoz whereas in the Corvette I am peddling the car to maintain traction. Same thing for the uphill esses and the left turn after the esses. With the Panoz I am flat out through the esses and can take that left much faster. In the Z06 I have to hit the brakes before entering the esses, then get farther left to straighten up the line over the "hump". At the top on that left sweeper the off-camber transition throws the rear end to the right much more than in the Panoz.

On the straights the Z06 makes up major ground. It accelerates much more quickly and reaches 147 vs. the Panoz's 138. I would like to try some 275/35/18 tires vs. the 275/40/17s to see if they allow more power application coming out of turns. Also, some sort of rear vertical plane (like Nascar used to be) would probably help. If I continue to run R6s I can spend 3 more points and may try some rear aero.

[Cobra4B]

A few other shots of other cars...




All done... successful weekend overall. She didn't break or make me touch my tools other than rotating the tires on Saturday evening and checking over the brake pads for taper etc. She does burn some oil like most 2001 LS6s, but that's fine... I don't mind adding 2 quarts of oil in the weekend if the 119k motor keeps on making 360 rwhp.



I took some good video as well, but it turns out I need to find a DV cable for my archaic video camera. BestBuy doesn't stock them anymore so I may have to order one.

-Brian

Videos

3rd session Saturday

YouTube - Mazdadrivers VIR Saturday Session 3

2nd session Sunday

YouTube- MazdadriversVIRAugust2010.mpg

[mariofromnewyork]

Nice write up and it seems your hard work payed off!

Im free this weekend if you want me to come over and show you how to change your rear brake light bulb.

Mario

[Cobra4B]

Originally Posted by mariofromnewyork

Nice write up and it seems your hard work payed off!

Im free this weekend if you want me to come over and show you how to change your rear brake light bulb.

Mario

Haha.... less light = less weight

[thegreenman]

Great job, looks like you had a blast.

[Munch]

Very cool. Glad the car is working out so well. Always nice when a plan comes together.

[allthrottleandsomebottle]

Fun times........
The 275/35/18s square will work nice.
Danny Popp and I found out the limits of Hoosier P275/35ZR18 R3S05s on the 97' with OEM Mag wheels. He was suprised how well it stuck........we liked drifting out at Oak tree though
Got about 8 MPG and put over 180 track miles on it that time
40-42 psi hot as I recall
Always good to come home unbroke

[Toque]

Looking good Brian !
Congrats on a well done project !

Keep all 4 wheels on the ground !

Toque

[wwomanC6]

Brain it looks like a lot of fun! Glad the car performed well.I can appreciate all the hard work you put into it! Awesome pics.

[Eagleeye]

Yes...Great pics and story line made me feel like I was there...lol . BTW what speeds are yyou getting on therun to turn #1 and the uphill esses ? I don't have the brakes to get over 135 on the backstretch as I have to start real early. Thanks for everything...Gene

[Cobra4B]

Originally Posted by Eagleeye

Yes...Great pics and story line made me feel like I was there...lol . BTW what speeds are yyou getting on therun to turn #1 and the uphill esses ? I don't have the brakes to get over 135 on the backstretch as I have to start real early. Thanks for everything...Gene

Har har har

Front sraight I tap the rev limiter in 4th then hold it there until the brake zone which is 146 on the speedo. Traqmate's GPS shows 142 on one of the faster laps.

Uphill esses I'm 120-123 coming into them and 109-112 at the top before hitting the brakes to turn left.

[Eagleeye]

Esses abt. 115 in and 105 at the top so I would be 15 sec. or so slower ? Jamie said she timed me Sat. [ my bad day ] and it took me 4:52 ! I'm presuming she missed me once ? What do you think...works out to 2:25 avg. was a bit quicker Sun. Slow or fast I had a great time...thanks

[WKMCD]

Sounds like a GREAT first outing Brian!

Remind me sometime to tell you about the time the hurricane came through Danville and my motorhome got stuck trying to get out of there. Funny as hell at the time until the herb wore off.

[Cobra4B]

Originally Posted by Eagleeye

Esses abt. 115 in and 105 at the top so I would be 15 sec. or so slower ? Jamie said she timed me Sat. [ my bad day ] and it took me 4:52 ! I'm presuming she missed me once ? What do you think...works out to 2:25 avg. was a bit quicker Sun. Slow or fast I had a great time...thanks

Sounds about right which isn't bad at all for street gear. Too bad Jamie couldn't hang out longer

Originally Posted by WKMCD

Sounds like a GREAT first outing Brian!

Remind me sometime to tell you about the time the hurricane came through Danville and my motorhome got stuck trying to get out of there. Funny as hell at the time until the herb wore off.

It was man... couldn't have asked for more. Hurricane in Danville? The heck?

[Eagleeye]

Said she was sunburning...Just remembered I kept hitting the windshield wipers downshifting...did it 3-4 times even ! Instructor said "you drive, I'll do the switches" ! VERY distracting ! Have a neighbor runnig his KART there 9/10-12 Top speed 130's but do the laps in 1:40's with handling

[Cobra4B]

Hmmm.... I've never had issue hitting the wiper stalk ever, but I have heard of some complaining about it over the years. Maybe has something to do with hand position.

[Eagleeye]

What was the verdict on Ryan's car ? Really courious...

[Cobra4B]

Broken timing chain! I've never been around that failed and the driver didn't know. Ryan said it just shut off w/o making any mechanical noises.

[Eagleeye]

Valve train damage you think ? First I've run across on an LS...

[Cobra4B]

Video added to OP.