I just bought an absolutely mint 95 LT1 ZF6 car (base suspension), and I'm loving every minute of it. About the only thing "wrong" with the car is that the shocks are 12 years old and not quite what they used to be.

So I was looking into new shocks, and figured why not go with springs/sway bars/bushings while I'm at it? I've been reading up on the coil-over vs leaf-spring debates lately, and I think I'm just going to stick with the leaf spring and make it work.

Has anyone used the Vette Brakes and Products Sport System or Xtreme Touring System? The Vette is not a daily driver, I enjoy stiffly sprung cars, and I'm hoping to start doing some DE events and would really like a nice suspension setup that instills confidence. Any feedback at all on the quality of components from VB&P? Any other leaf-spring based kits out there I should consider instead?

Thanks in advance!

Matthew

 

the only real problem with the coil overs is that they will put you up a class in most road course organizations.

 

I would just see if you can buy the z51 springs for that year (oem) GM spent millions getting it "right".

And get adjustable shocks so you can tune them to YOUR liking.

 

Thanks for the great replies!

So I've checked out the Corvette Action Center Suspension Chart:

http://corvetteactioncenter.com/tech/c4/susp_chart.html

Let's say I find a setup that I like listed in that chart... Is it as easy as calling up the local Chevy dealer to get the right springs? Just tell the parts guy what year and suspension package I want? How much do the OEM springs run price wise? Anyone know what the spring rate is on the VBP sport and xtreme springs for comparison sake?

Matthew

 

As a manufacturer of the composite fiberglass springs, we can make any spring rate you desire. Our standard rate ranges are listed below. If you call us and describe your driving style and what you want to accomplish, we can set you up in the best spring type and rate to suit your style. It is not only the rate that is important, it is also the type of arch/mold we use for the different style types we have.

We offer a 10% discount to Internet Forum and Corvette Club members and would appreciate the opportunity to discuss your project further and quote our products. You can contact us via email at pattie@vbandp.com or call us toll free at 1-800-237-9991 and speak with either myself or Gary.

C-4 '88-96 Front Stock Spring - 270 to 350#/inch
C-4 '88-96 Front Sport Spring - 450 to 550#/inch
C-4 '88-96 Front Extreme Spring - 1000 to 1250#/inch

C-4 '84-96 Rear Stock Spring - 340 to 380#/inch
C-4 '84-96 Rear Sport Spring - 480-510#/inch

These are standard rate ranges and can be varied. Depending on what you want to accomplish and how you want the ride to feel and the ride height to look like, we would determine the arch style and whether or not to put you on the low end, high end, or in the middle.

Pattie
VBP

 

I installed the VB&P springs/shocks/sway bars/bushings setup in my 87 coupe around 5 or 6 years ago. My spring rates were comparable to Corvette challenge springs I believe. It is definitely very stiff on public roads, but I 'think' it handles better. I have not been to any timed events to actually prove it handles better. VB&P did a good job trying to service all of my problems with the project.

I have a few issues that they may have resolved since I worked on mine. I couldn't get the stiff front spring to sit down lower than stock. They gave me a prototype spring to try, but the first spring worked better and I have 2" of gap between the fneder and front tire. I never got the aftermarket 32mm front bar to fit. The end link angle would just not line up. The rear seems under shocked - meaning bouncy. The bushings took some fitting and new sleeves so the sleeves would rotate in the bushing as opposed to the bushing rotating in the suspension.

How many miles on your car? Ball joints, tie rod ends, poly bushings, and shocks might give you all the improvement you are looking for without going too stiff.

 

 

I put the 32 mm VB&P front swaybar on my 93 base model and the autocross results were astonishing.

I've heard good things about Koni adjustable shocks (other than you have to take the rear ones off to adjust them).

just to make things easy to compare vs. the suspension chart:
C-4 '88-96 Front Stock Spring - 47-61 N/mm
C-4 '88-96 Front Sport Spring - 79-96 N/mm
C-4 '88-96 Front Extreme Spring - 175-219 N/mm
(stiffest stock C4 springrate was 115 N/mm)

C-4 '84-96 Rear Stock Spring - 59-67 N/mm
C-4 '84-96 Rear Sport Spring - 84-89 N/mm
(stiffest was 87 N/mm in 1984, never used again)

 

If you go oem (as I did) you should be able to order thru a chevy dealer. Having said that it's sometimes hit/miss with dealer parts guys if you know what I mean. I have a local dealer parts guy who works with me very well with hard to find older Vette parts. You may not be so lucky.

I had to go oem because of SCCA racing rules & stock classes, if you are not concerned with stock class racing rules you may be better served by a company like VBP. They will "know what you are talking about" more so than a dealer who has not ordered a C4 Vette spring for years (if ever).

Having said all that, I agree with the poster who said to make sure everything else is up to spec b4 you go changing springs.

When I did just shocks & bars alone it was a dramatic improvement. My bushings were good. Wheel bearings, ball joints etc. are all factors. They all wear out eventually.

 

I just bought a pristine 1989 Z51 coupe with 47K. For a 17 year old car all I can say is WOW! A good path may be to duplicate a Z51 layout. Spring rates and Bilstein shocks can be easily duplicated and are availible.

 

Took a tour of Bilstein 2 years ago with my car club, they were very accomidating! Very impressed with their product, they personalized the valving on our T bucket several times till it was just right (no charge), and were very helpful. I don't remember the guys name who helped us there (D@#N CRS!), but I'll look at home and see if I can find his card!

 

I was very pleased with the difference that a 30mm front stabilizer bar and Z51 Bilsteins made to my stock suspension 95. Try this before you go to HD springs. The adjustible suspension car all use non HD springs.

 

I think you will be pleased with the results if you put a set of good adjustable shocks on the car and get them dialed in. Stiffer springs do not always yield better handling, especially if the road/track surface is rough.
Start with Koni Sports or QA-1 units, get them set up, then see if you feel you need to go further. You may find you do not, especially if you drive your C4 on the street.

Larry
code5coupe

 

I think that statement would be incorrect....

MY Z07 FX3 has the HD springs matched with adjustable shocks...from the factory.

Match that to a nice set of Bilstein "tuned" shocks and a DRM FX3 controller and my car can stay well ahead of most others wanting to "play" at the track...even before I added 150+ HP to the equation.

Also, as a word of advice, don't make too many changes at once. Like others have already said, change the bushings, ball joints, tie rods, etc. FIRST and get the car aligned. My Z07 (which I purchased new) HAD ABSOLUTELY apalling handling at around 40k miles. When I pulled the control arms the holes through my bushings were oval, and this car was (and still is) well-maintained.

I changed EVERYTHING in the suspension and had a new car all over again....then changed out some bits & pieces with some DRM modifed ones...what a difference....

 

I guess I've always liked the "feel" of a stiffly sprung car. My father had an 89 Convertible (base suspension), and I loved the way that car felt. Looking back at the Corvette Action Center link, I can see that the rates for the base 89 Vert are a bit higher than the base 95 coupe.

I'm thinking 91 Z07 rates look pretty good for a weekend-only frequent DE car. Anyone have that setup and regret it?

I do plan on getting the suspension rebuilt as much as needed - bushings/ball-joints/etc. Can't wait to see how it handles after all this.

Matthew

 

I think you'll be happy with the Z07 setup...I've got it on my car. It stiffened up a bit when I had Bilstein rebuild the shocks (using Rippie's valving) and the new controller. If you have a base suspension car, then a nice set of adjustable shocks should work nicely.

I LOVE how I can go from a nice, firm ride to stiff-as-an-'84 with the flip of a switch...some can badmouth the FX3 system all they want, but mine has only had 1 shock actuator go bad since I've owned the car (since Jan. 1991). I've rebuilt the shocks once....and the car gets driven HARD at the track and in autox. I think I have 80k miles on it now.

Like I said before, if you change out everything in the suspension at once (ball-joints, bushings, tie-rod ends, and BEARINGS) then get the car aligned you will see a dramatic improvement. If you choose to change the springs out at the same time, you won't have to go back to square one. Most people change out bushings and don't do anything else, but the rest of the suspension has just as much slop in it as your bushings. They change one thing, get it aligned (for $100 or so a shot) and have to go back and do it all over again when they change out ball-joints (or tie-rod ends, etc.). So you end up wasting a lot of money to get it aligned 2 or more times.

I got my set of bushings from DRM...I laid it out on a spreadsheet before I started and they had the best price for black urethane bushings hands down. I got all my hard suspension parts from GM (I have a friend who is a dealer...I get parts at dealer cost plus 5%).

Good luck...you won't regret it.