toy4speed

Hey All, first time Corvette owner, a 2008 Z06, long time autocrosser. Enjoyed my few events in A-Street class with SCCA this year, with basic mods (thanks Stranoparts.com), koni sports, strano front sway bar, BFG Rival-S in 275mm/335mm, catback Corsa Sport, autox alignment. Pretty simple mods, car feels good, just trying to find any other fine tuning areas to improve a bit more.

Couldn't find much Googling in C6Z autox prep, perhaps 'cuz the car has been around 12 yrs already, or A-Street doesn't lend itself to much mods, or not many owners autox C6Z models, I don't know.

Hoping to get some conversation of things C6Z owners have tried, liked, or not liked. Future plans, perceived strengths and weaknesses of the C6Z in autox. Yeah, seems like it could have been in a conversation about 10 yrs ago, but I thought maybe after a decade or so, some new thoughts/ideas may have come around, if willing to share.

For me, I plan to try both of the sway bar settings on the front (currently on softest), play with alignment some more. Went from 1/16" total rear toe-in, to 1/4" total toe-in. Can't say much difference felt. Trying to get a bit more traction accelerating out of turns, might try less rebound on the front shocks. Already down to about 29 psi on rear tire pressures. Not sure of the performance benefit of various brands or rear diff fluid, but wanted to explore that option too (currently on OEM fluid).

A-Street is a very fun class with the C5Z, C6GS, C6Z, C7, and a small mix of non-Corvettes too.

I figure there are always new owners of the C6Z model entering autox, and this thread can help answer many of the basic setup questions, and shared experiences can help everyone.

Don

Nokones

Hi Don:

Get a hold of Rich at Able Chevrolet. He can help you.

toy4speed

Thanks Ken! Rich is a great guy! Almost time to go visit his shop for some service items too!

All you super fast guys in CAM have so many mod options, but I'm trying to get opinions from those in the Street Class. I have a number of ideas, and being in Street Mod these past 6 yrs I often think anything is possible ($$), but the rule book reminds me its a different game in AS.

Don

boony1968

For pressures, lower feels better / faster to me but I idk if it actually shows on the clock. I've found shoulder wear gets much worse below 29lbs. I usually set at 30 cold and bleed down to that level as tires warm up. In my GS, I run the same pressures all round, in my Z I ran the fronts 2 lbs higher than the rears (31/29). Pull the spacers on the upper control arms, max out your front camber and run the rears at -1.7ish. Zero toe or a little toe out for the front and 1/4" toe in for the rear. Also, run with a full tank of gas to help corner exit grip.


It may seem like the conversation has died down but that is only due the fact that the setup for A Street is pretty straightforward for a C6Z. With the Koni's, Sam's bar, a proper alignment and the BFG's your car has everything it needs to be nationally competitive.

toy4speed

Hey Boony, thanks for the feedback! My current setup mirrors your comments almost exactly. I'm thinking this basic package gets the car (not me, just an average driver) up to about 90% "developed". Most autoxers are always looking for that little bit extra in tuning, or development. My own ability may be self limited, but I enjoy the challenge of building the car.

I've noticed the full tank of gas (going against my old habits), noticeably helps the rear end with traction. Good thing we have lots of torque!

I have my rear lowering bolts full low, and the front is about 1/2 way down. I am cautious about too much rake making the car loose. Anyone have feedback on ride height adjustments?

Played a bit with shock adjustments (koni sports), think when rear rebound was increased to 4 sweeps, car went briefly into ice mode when hard braking. Makes sense too much rear rebound could cause this. Anyone experience same?

Don

mattastick

Assuming the C6 is similar to a C6, rear toe is a huge tuning tool, and small changes make a big impact. So, I'd focus on driver until you can feel small toe changes. Then worry about parts. Your car is capable of a podium/jacket at Nationals, with the parts already on it. Time to spend time/money on driver development.

toy4speed

Oh definitely! Way more to be gained working on driver than car for sure! The car has already shown to be very capable as it is, but I know there is more there too.

Never trophied at Nats in 20 yrs. This car might be my best chance.

Don

boony1968

As written, your rake is backwards. For autox and street (no crazy track speeds) rake can be zero. Up to a quarter inch higher in the rear is fine. Within this range the rear may appear slightly high or unbalanced due to more fender / tire gap. This visual is caused by the smaller than stock diameter BFG's. Stay at least a couple full turns off full drop in the front. Full low in the front is too low.

There's plenty of info on this site on how to measure for setting rake. Once that's done, get a corner balance and realignment.

toy4speed

Let me clarify. I lowered the rear more than the front, using the stock lowering bolts. Not really much height change overall. I'm not assuming that at stock height, the car has a perfectly level rake. So whether my current rake is backwards or forwards, not sure. Height adjustment from stock seems to be pretty individualized. I didn't arrive at those changes myself. Not to say one person or another's is right or wrong, but rather what subjective effects on handling resulted from the changes.

Thanks all for the posts.

l98tpi

I have a Z but run CAMS and modded. However, I have got to run a stock C6z once and like the power and feel of the car. With A street you can only change one anti roll bar and sounds like you did front. You said you are loose on the rear and on softest setting on your front bar. Change the front bar to hardest setting. Something else you can do is raise your tire pressures in the back. Good Luck

Also, the best car mod is the driver mod, so seat time, seat time, seat time ����

toy4speed

@l98tpi: Thanks for the suggestion! I plan to try the front swaybar on the stiffer setting this weekend. Measuring rake at the front and rear jacking holes, seems currently my front is 3/8" lower than the rear. I guess the car has a bit of rake. From everything I have read so far, this amount of rake is certainly in the ballpark of ok. I will probably play around a bit with the rake (up and down), just to see if I can notice a 1/8" change in rake.