Bill Williamson

My car has a lot of oversteering when on a road course. NO rear sway bar. Front is 7/8'' with new bushings but is a bit worn at the holes thru the sway bar. Have been told that a 1-1/8" front and 3/4" rear would be the ideal package. Have also read that addition of a rear sway bar will reduce any understeering problems??? i have OVERsteering problems without a rear bar and cant see how the addition of a rear bar will help the oversteering problem. I have Goodrich 245/15 T/A Radials on front and 255/15 on rear. In general, the car rides and corners well by comparison to other stock c3's ive been in.

hugie82

Maybe if you drop the rear an inch might help.

larrywalk

Adding a rear bar will make the oversteer problem WORSE. The 7/8 size front bar is too small - try a 1 inch or 1 1/8 inch front bar. And then, if you feel that you now have too much understeer, add a small rear bar like the 7/16 bar used with some of the big block cars.

It's hard to imagine that a 3/4 rear bar would ever be optimum. I have one hanging on my garage wall, but it's handling is frighteningly loose - never again!

doctorgene

Mr. Bill
I had the same problem, adding the rear bar, at 70 to anything above, I felt like the car was going only where it wanted to. A couple of nice Corvette Forum members talked me into taking it off. Man that was the best thing I ever did, all my suspension had been rebuilt when the sway bar was installed. Scared the you know what right out of me. LOL Have a great one, P. S. I had lots of buyers for it on the forum, people still want to put them on. Gene

TheSkunkWorks

Stiffening the rear's roll resistance relative to the front, whether with a higher rear spring rate or larger rear bar, will increase oversteer. So, to reduce oversteer you want to either reduce your rear spring rate or increase the front spring rates or install a larger front bar. If you don't already have at least 550#'s up front, suggest that be your first move. Hope that's worth $.02


TSW

7t3shark

FWIW in my autocross days I used 1.125" factory front bar and the 7/16" factory rear bar w/ factory springs all around. 255/60-15 all four corners and tire pressure in the 38-42psi range. Made for near neutral handling.

doctorgene

TheSkunkworks: Mr. Charlie,
Thank-you again for your help on my rear sway bar, Removal. I Appreciate.
7t3shark Where is John Galt, We need him greatly. Have a great Life you guys. By the way, I dropped my rear end an 1 1/2 " when I was having the over steering problem, didn't help. Gene

Solid LT1

I wouldn't run a rear bar on a open track C3 Vette. I was thinking while reading your description that you may have another problem going on and, that would be "toe steer" in the rear suspension, shoot a photo of your rear suspension at staic ride heigth and we can further discuss your problems. I think you will find that your rear half shafts are level with the ground or even worse, the inner center is lower than the outer center which will cause massive toe-out and EVIL handling. Are all you rear suspension components in excellent condition? is your differential fresh with minimum side yoke play? Many factors can effect C2/3 Vette handling.

jb78L-82

Some good advice here especially about increasing the front roll resistance with a bigger bar/550 springs, decreasing the rear roll resistance with a softer spring, and checking all the rear suspension components/alignment. I run a stock 1 1/8 inch front bar with poly mounting and end link bushings and 550 springs. In the rear, I have a 360 composite spring with poly mounting bushings, competition strut bars with heim joints, and a 3/4 in rear OEM type (not an aftermarket end linked bar), Bilstein shocks (front HD's and rear sports), with 255/45/17 ZR's in front and 255/50/17 ZR's in the rear. The car is very neutral at the limit! You need to customize your setup to address handling issues. I made all the changes one at a time over 25 years, not all at once, to get the neutral effect. The car is a F-41/gymkhana suspended C3 and came originally with a 7/16th rear OEM bar. The later 70's small blocks hand the 7/16th rear OEM bar, not just the big blocks.Hope that this helps!

69autoXr

I think it's about time for a sticky regarding sway bars.

TheSkunkWorks

...but, there's a good chance the fundamentals would likely end up lost amongst all of the bickering that would surely follow over opinions of what works best (as if there were a one-size-fits-all setup).

Jim_Harrison

I also suggest you have the rear alignment checked. Toe out in the rear can cause big trouble. I little toe in makes them a lot more predictable.

I just replaced my front bar from 1 1/8 to a 1" to resolve some understeer problems I have a the National AutoX course in Linclon NB. I run 860lb springs on the front with custom valved Koni's, no rear bar with custom Penski shocks. I think without the high end adjustable shocks, I would want to run the stock F-41 9/16 bar.

Bill Williamson

Thank you all for the help...
Have decided to go with the 1-1/8" front, a complete re-alignment and then add adjust as i go......