polo91cnvt

Looking to, slowly upgrading my '91's suspension for autocross and would appreciate some input before I order a new set of sway bars. My ultimate goal is a full coilover suspension.
Who has the best sway bars for autocross?
What are the current bars on the market, Van Steel, Mid America, Corvette Central, Ecklers.... any others?
Are these better than old stock and why?

I have heard from the forum that the full coilovers are expensive and not the best way to go due to tuning issues, but from the discussions with professional racers given the choice of the stock fiberglass springs and going to coil overs, the go with coil overs. So I am kinda set on coil overs.

That said, any input on the sway bars?

Thanks, Polo

l98tpi

Vette Brakes, VB&P, specializes in suspension components.

If you are just starting to autox, learn with the stock suspension before starting upgrades. Once you learn to drive, then start your upgrades.

PLRX

Contact Van Steel and speak with Paul.

I guarantee you great customer service, support and Vette parts

www.vansteel.com

polo91cnvt

Thanks I will call Paul.

Polo

kimmer

I'd go with a 32 up front and a 26 out back. Oh that's right, that's what I did.

polo91cnvt

To all, I am past the novice level at autocross and starting the build on the car. So the 32mm front and 26 rear is the same as stock and the stock appear to be tubes. So are the repacements any better? How about the solid bars, while they add weight are they any better?

Thanks, Polo

rfn026

DJ Race can make your rear sway bar adjustable.



Richard Newton

Alan777

No c4 came eith 32/26 afaik.

jaa1992

What is the CAR telling you then?

What class, restrictions on the class?
So if you call VBP and tell them what you want to do with the car they will sell you a suspension package.

Or you can call the recyclers and see if they have a Z07 suspension laying around. Or just the sway bars, or go adjustable, etc. Etc ETC

kimmer

If you are so seasoned you should know by talking to other drivers that 32 & 26 are not stock.

l98tpi

The 32mm and 26mm are not tubular, they are solid. As far as weight, they don't add much extra weight, maybe 5 to 10lbs max. You definately will notice a difference. You may want to get a good alignment after installing the bars. The bars are going to reduce the roll charcteristic of the car. Another upgrade after the bars or maybe before if your wallet allows is higher spring rates.

Sidney004

Aardwolf

The best? A custom made adjustable bar.

Go with tubular bars and save yourself some weight. I made a thread about rates here:

http://forums.corvetteforum.com/c4-t...l-options.html

Here are some pix from my last event in fall showing how the 1.25" and 1" tubular bars are doing (can see camber too):

http://f-51gtphoto.smugmug.com/2011N...0538&k=TdXsNqZ

Hoosier R6's for tires, 1.25" and 1" tubular bars. Got them on a nice VBP sale.

BTW use heim links, especially for the rear bar.

Canam

The 85 Z51 suspension comes with F30mm and rear 24mm. Thats pretty good. I run the Z51 30mm front bar and the Convertible rear 22 mm bar. Keeps the rear end planted. You can get them cheap from the wreckers.
My car is a race car @2880 lbs. Handling is very neutral. I run 27psi front and 29 psi rear on R1's.

rfn026

We're a little limited on sway bar selection. We could actually use something bigger than the old Challenge bars. The solution is to use stiffer springs.

Normally this is not something I would do. Then again you race the car you have. I went with the Hyperco springs from Corvette Central. Not only did the car get flatter in the turns but these springs also dropped the car a little.

I rune the Challenge springs with Z51 sway bars. The rear is adjustable. I normall get the same tire temps on the front and rear of the car.

Richard Newton
101 Projects

ScaryFast

Sounds like a recipe for understeer...now I gotta go check my bars and see what I'm using.

What size tires? Square or staggered?

indianavette

For what it's worth, Tommy Morrison, who did lots of C4 handling work for Liteflex and Corvette engineering and won more IMSA and SCCA endurance races than anybody, ran '84 Z51 sway bars (26/22mm, I think)and shaved FHBs (115.5 N/mm) in front and stock NYUs (57.2 N/mm) in back most of the time. Here's a before/after look at an FHB. Sez shaving lowered nose with minimal effect on geometry.
[/IMG]

polo91cnvt

To All,

Again, thanks for the input this is great, and has given me some followup work, but here are answers to some of the questions;

I am running in NCCC class E3 9 the car has modified intake and a cam. In SCCA I run Super Sport Street Modified with street tires.

I checked the FSM and figured out that there were both tubular and solid swarbars used in the '91, but it did not tell me what I should have. I need to track down a sheet I have that lists the suspension specifics. That said I measured the swaybars on the car and the front is a 32mm and the rear is a 26mm and if my memory is anyway near working (51% posliblity of error) that was listed as the stock size. The '91 is a convertable which i believe makes a difference. With the different bar sizes noted in this thread I am at best getting confused (a very easy condition to reach).


To Indy, Sorry I don't have the manual with me for the FHBs and NYUs to figure out the acronym. Kindly enlighten me.

Again many thanks to all of you I am learning a lot, Polo

rfn026

275-17 Front
315-17 Rear

28 lbs cold Front
30 lbs cold Rear

I'm maybe 1 or 2 lbs too high here. I'll know better after the next track day.

Inflation

If the center temperature is higher than the average of the inside and outside temps, the tire is over inflated -- try reducing the pressure in 2 lb. increments.

If the center temp is lower than the average of the inside and outside temps, the tire is probably under inflated -- increase the pressure in 2 lb. increments. Once the pressures are set correctly, then look for major differences in temperature side to side.

Richard Newton

USAsOnlyWay

30/26

315 square

Still felt a little too much understeer so recently changed springs, super stiff 84 z51 in front, z51 stiff in back , sore guts inside
Haven't had a chance to test it yet.