Shaun R

I am the proud owner of the softest spring C4 ever made and tired of going around the road course on the bump stops all the time. Take a look at some of spring options out there and not really sure which route would be the best choice for me. Debating between some replacement GM stock 89 z51 springs, DRM coilovers or the vette brake parts. Not trying to turn this into a coilover v. leaf debate, just looking for some opinions as to what will get me the best bang for my buck. Car only sees the track maybe 5 times a year and no interest into turning it into a track only car. Is it worth trying to track down used springs that are that old?

John Shiels

DRM coil-overs would be nice and the VBP products work great also. Comes down to $$$$$$$ If you could find some stiffer used springs that's great too. If you buy used and do an install and your not happy it may not be worth it. Personally I really have to trust the person selling the used springs. Have the C-4 springs changed during the production of the C-4? That may limit the used market for you.

Shaun R

Generally as the years went on, the springs got softer. Softest being the 96 cars. All springs 89-96 are interchangable but I can't use anything from earlier models due to suspension changes. Only think that makes me uneasy about used is that the parts would be around 15+ years old for the good year springs and im not sure how well the fiberglass holds up over the years only to be subjected to my abuse on the track. Need to look into new but down the stealership still sells them due to age.

Slalom4me

I assume you have an '89 with the FE1 package.

Contact Patty at VB&P to see if she can find you a rear
spring between 330-350 lbs/ft. My understanding is this
is below their target but that as they test springs coming
out of the molds, some register low.

Have her also send you the 10" spring adjuster bolts and
either get her isolators (rubber bushings) or buy four
#10262518 Insulators from GM.

The front FE1 spring is fairly stiff in '89. With a rear spring
as mentioned, the bottoming goes away. Z51 Bilsteins,
various R-D supports and sway bar tuning complements
the rear spring.

.

John Shiels

if you go DRM coil-over then you won't need the cost of shocks added like springs

Shaun R

Nope, its a 96 FE1. Below is the link of stock springs so you can see how soft she really is. And I know its hitting the bump stops because that area of the frame is usually the cleanest part of my car after an event. Low speeds, under 70, its workable, but anything over those speeds and the car will just bounce if I do not set it perfectly going into the turn.

http://vettenet.org/susp_chart.html

Shaun R

Already doing the "shocks like springs" thing. Front konis are cranked up all the way and backs are at about half. Can't be the best setup but anything less on racetire was to slow to turn in and washy.

Slalom4me

Spring Rate Conversion Factor appears in this
thread about Z07 springs over in C4 Tech

.

John Shiels

Nice chart. I'd like to dump my GS springs they are to soft for me. I see how the ZR-1 springs went soft as the years went by

Slalom4me

Oops, only glanced at the '89 reference in the initial post.

.

Shaun R

Jumping off topic, but if I do coils then i'll go stiff and probably endup needing my koni singls revalved. Any idea on who I does this that knows there stuff and about what it runs?

Sidney004

Now I am really starting to feel bad. My 94 FX3 has the same spring rate as yours. Does this mean I now have to spend more money and change my springs!

landpilot

I went from the buckboard ride on my 84 Z-51 to 94 front and rear springs. It made a big difference. Not sure exactly what the codes are on the springs, but it raised the car height an inch or so and it still corners very impressively. My issue now is tires, more specifically 16 inch tires. I have the BF Goodrich Comp T/As and they are stiff and not very good on wet roads. I'd like to get some Michellins, but I don't think they carry a 255 / 50 /16 tire. I have a set of original, very new looking rims, so I'm in a quandry about going to ZR-1 17 inch rims. There are lots more tires in the 17 inch sizes and I could go with larger rotors if I did that. This need for speed is turning into a money pit.

AUTO_X_AL

The 84 Z-51 is the way to go if you can do it. We busted a spring last year and bought a privte party original 84' z-51 and it has held up to some impressive punishment. The fiberglass should be fine so long as everything is intact with no splintering and fraying. And if "buck board ride" means FTD count me in. I know there are suspension diffrences from the 84-87 to the "Zero scrub radius" 88-96. I have heard of those being retro fitted and even c5 springs being put on. If you dont mind modifying a bit you should not have any issues.

inadequate

Comin in 16 years later lol
I've got a 96 LT4 car with the F45 suspension. I've been researching what my spring options are. I'd like to get used stiffer ones. Probably do the NYU in the back and FSK in the front. As far as I can tell from the chart I have a 24mm solid anti roll bar in the back and a 26 tubed in the front. I was gonna replace the front anti roll bar with an aftermarket 32mm or 30mm, was going to leave the 24mm in the rear as it is. I was thinking of doing the Z51 Bilstein shocks, but not sure which shock would work best here. Also I want to lower it an inch or so in the front and rear. I'm gonna do 17 x 9.5 A mold wheels with 275-40-17 high performance all season tires. Basically this is a street car driven a few times a week for fun. I don't really have any plans to autocross it or bring it to a racetrack but maybe at some point I will just for fun. I want to have a setup that is firm and handles really well and tight, but isn't too harsh for the street.
Does this sound like I'm heading in the right direction as far as having a great handling street machine?

Thanks for any help if people see this

Aardwolf

That's a fun good handling setup! That combo I didn't think was to harsh of a ride till winter with freezing temps and then the roads are cold and bumpy. Old race challenge springs were inexpensive and available plus after market when this thread was started, now I would go to a coil over kit. There have been a few new options talked about in C4 tech. It would be good to talk there too.

93Polo

I really liked my '93 base suspension with single adjustable Koni's on the street. If I were going to the track I'd do more but the setup worked great on aggressive mountains as a 20 something year old.

If others need it:

https://www.corvetteactioncenter.com...uspension.html

inadequate

ok thank you!

inadequate

thanks for your input!

Kubs

Van Steel is now making their own springs which should be available soon. They also have some pretty cool sway bars for the C4.

https://www.vansteel.com/index.cfm?f...subgroup=32033

https://www.vansteel.com/index.cfm?f...subgroup=32024