im runnign 29 inch tires but they have to mcuh roll and are hitting the sway bar. were can i get like 25 and 26 inch tall hoosiers. i get my tires now from my uncle for free.

 

Hello

Did you install these with the body on? Their website says the installation is "very difficult" with the body on the frame.

How do they work?

 

The best hookup for race tires is Bob Chick. He gets gently used stuff from vintage races and resells it to people like us who can't afford new tires.

Bob Chick
RC Enterprises, 2155 Coker Ave, Charleston, SC 29412
(843)762-7324- office
(843)762-7168- fax
usdrctrs@aol.com

 

Yes, I installed them with the body on.
Yes, Very difficult!
Took me like three hours to do one side. Not including the R&R of the trailing arm. This was just for drilling the holes, & welding in the adjuster. The bolt that holds in the trailing arm was the hardest part. It is so long that getting it in place with the trailing arm was a real nightmare. Now that it is done it's great. The alignment guy really liked them. I have not messed with them much at the track. Still learning how to setup the rear. Figure on some down time. I installed Guldstrand steel bushing's for the trailing arm's at the same time so this could be why it was so unforgiving. It's suppossed to be.
Later!

 

Man, How do you guys run such tall tires?
I can barely get away with 26.5. I have my rear suspension ride height to almost max to keep the fender off the tire in the corners.
When I get flares I will be OK.
I run the hoosier vintage bias ply's. I get them from http://www.rsracing.com/
They have the full line of hoosier tires. They also carry the real racing wheel line. Check them out but their not free!!

Could you run the 29" tires if you had a wheel with less backspace?
This might keep them off the sway bar.
Do you need the sway bar?

 

I have 31" tall tires on 16" rims (and 16.50" wide) Body mods is the only way to make it fit.

 

i might not need it im not sure. i actually havent competed at a race yet. do you think i need one?i just did some testing in these brand new roads with nothin around.

 

Wow! That statement is a can of worms.
If you have not been on the track yet. You really don't know what it's gonna do! The track will bring out every flaw in your car. Just look how many people on this forum are modifying.
It completly depends on where your car is now and what you have done to it in preparation for a track day. I can guarenty that if the tires rub now on the street they will rub worse on the track.
Good Luck and have fun!!
Kiss your bank account goodby. LOL
Later

 

i dont think i have enough air in the also. one of the front tires was rolling onto the side wall. before i go i whould put equel pressure in.

 

hey all,
jim, first thing i would say is... cheat.
basically, you already are according to your rules with the aluminum heads, etc. if you want to be blatant about it, get some 17" wheels. you could be sneakier with some 16" rally styles though. either way tires are definately going to help alot.
like some others have said, these cars are notorious for oversteer, specifically snap-oversteer. if you have a rear bar, take it off. it will only exaggerate the issue.
if you can't run an R compound, i'd run a low pressure like 20-25psi in the rear. it'll give the back a little slip to telegraph what's going on and still give you time to catch it. in the front, i like to run ~40psi, depending on the track. like anything else with track events, this is all just a starting point and you have to play with it depending on the track and conditions.
next, i'd suggest seriously evaluating your driving style. i have no idea what you drive like but when you say that you push going into a corner and slide out, it sounds to me like your not being as smooth as you need to be or your just overdriving the car. i'm a victim of that myself but shear will simply cannot overrule the laws of physics. to go faster, you need to slow down. practice being smooth and nailing your lines. i've found (to frustrating effect) that in almost every case that i'm as fast or faster when i'm just trying to drive smooth fast than when i'm trying to drive ***** out.
c3's are notoriously finicky handlers. i believe a large part of the problem is that the more you stiffen the suspension, the more the frame becomes a "spring" member. i support this hypothesis because i managed to crack my windshield from A-pillar to A-pillar at a track event, on street tires no less. you need to do as much as you can or are willing to do to take the flex out of the frame and put it into the suspension like it's supposed to be.
as i see it (just my humble opinion) a major problem alot of people have when modding a c3 is following the advise of gulstrand or greenwood on how to set up suspensions. many times the results are less than desired because the two G's build race cars. typically, the first part of their car preparation involved gutting the car and pulling the body off the frame. if your not planning on doing that, you won't see the same results out of that 800# front spring package.
i don't know how much this will really help anybody and don't claim to be any type of expert. i appreciate the kind words many of you have said and hope this puts a couple fresh ideas out there for a few to try. it's good to see these cars out on the track from time to time, and even better when a few of the c4 or c5 drivers show you some respect.

 

OK, You asked for more.
I did the best I could converting this.
These are from California Speedway March 2005.
#1 is a couple of laps showing the exit of the oval with a good run on a porsche.
#2 is A lap with a good infield pass on a couple of c-5's.
#3 is the same lap but inside the car.
ENJOY!!
Video # 1

Video # 2

Video # 3

 

It is a real pleasure to see a C3 out bombing around on a track and doing so well. Hell, it would be a pleasure even if you could only barely keep up! It must be quite disconcerting for at least some of the folks in the newer machines to have a 30+ year old sports car give them such a hard time.

Wherever he is, Duntov is smiling.

Don't be shy about posting more vids if you have them!

 

damn dude, you run hard. Thats great. I don't know if i have the ***** to hold the hammer down on the large part of the track like that. that smallblock 434 gives you some serious power.

 

Turtle with your lean in the second picture. You might be on the bump stop. 72 RAY trimmed his up. I just removed mine as excess weight.

I was also thinking that without a passenger the body roll would have been more. I can really tell the difference of how my car drives with a passenger.

I had a couple of friends stay at my house during a local track weekend. Since they had not run the track before they had to get the OK from passenger seat driving instructors. I told them ahead of time to get an instructor with a simular car "Vette" It doesn't do you any good to go out with a Miata track champ.

 

Lots of good stuff here Don't forget about safety equipment as you add speed to your vette. I laugh when I hear someone complain about the cost of a bicycle helmet being too much at $40+, I just wonder to myself what price they have put on the value of their head Safety items are always a good thing to consider in your budget

Assuming your suspension is in good working order, I found that stepping up to the larger wheels really improved the handling of my vette. This was felt the moment I first drove the car on the street, and the ZR tires had much better grip when autocrossed. If you're still going to drive on the street, this is a very good upgrade, but if you're looking to build a race only, then sizing race slicks would be the obvious choice.

 

There is one downhill turn at Lime Rock where i know i'm on the rear bump stop and that will cause the rear to kick out in a heartbeat. It gets real hairy in this car....its not like a lot of other cars where you have a lot of notice before you exceed the limits. I will experiment with totally removing the bumpstop just for racing and leaving them in for the street. The have saved me a few times from destroying the bodywork when i've broke spring bolts.

From what i've experienced you can't have too much spring rate for the track as long as its balanced correctly. I'm getting all that roll with 550/390 springs I have the stiff Koni shocks too.

I just need to get some decent tires and that will help a lot.

72 Ray looks kick as$. Do you have any pictures or videos? I need to get a cheap video camera. It helps a lot to analyze what your doing right and wrong.

I can tell the difference in the car without an instructor. It definitely feels more nimble.

 

I personally thing removing the bumpstop altogether is a bad idea, especially if your suspension bottoms out on it and you know it. The bump stop is your last resort and it's a sort of progressive rate spring that when compressed more gets very stiff, the suspension slamming into the frame however is an every more harsh travel limiter and will give an even more violent reaction. I would trim down the bump stop bracket or weld studs on the frame so you can bolt one straight to the rail, that should save a goog inch or so in wheel travel.

Shocks only dampen violent motions and will not dampen a rolling motion, you need either stiffer springs, a stiffer set of sway bars, a lower ch or a combination to get rid of it, however stiffer bars mean more force on the tires (since there's no roll the full weight displacement has to be absorbed by the tire so the limit of adhesion is reached sooner..wider tires are the answer there)

 

I'm not a fan of removing the bump stops, if your hitting them, then correct the issue

 

Turtle - You got me thinking about a few things. I just figured that i have stiff enough springs and a lite enough car to never hit the bump stops. So I removed them.

Then i just remembered this spring when i blew out a front shock. It had oil everywhere. It probably bottomed out on the local track and blew the seals. I just figured that it was 3 years old and the fact that I crossed a bad course bump while really braking. It wasn't normal at all. I actually felt like i was completely out of control. The local race track since the expansion of adding more length has become unsafe for the faster cars

The bump stops probably prevents the shock from over compression. I also talked to somebody about running a shorter shock height with the one inch shorter springs. Vette Brakes can get them.

 

I agree, even though the chevy power manual says to remove them. I'll buy a new set and progressively trim the old ones.

The car was sitting around 1" lower than stock to begin with so the suspension travell was limited to begin with.