I have a set of koni yellows on my 82 z28. I'm looking at springs and none of the aftermarkets list the rates. Most just talk about lowering the car. I'm trying to build a car that can handle better than my stock iroc. I'm current set up isn't right and wanted to know what springs others were running on their cars for autoX and if anyone does any road racing? Also does anyone know where I can find the rates on the aftermarket springs on the market?

The Eibach ProKits are 714 front, and a variable rate in the rear. I think it's like 110-170 or somewhere in there. But don't quote me.

I have also got the Eibach Pro-kit springs and all those other goodies on my car. Unfortunately, I wasn't able to make it to the last autocross event to push the car and put them to the test. Oh well, that's for next year... maybe LS1 brakes will come next year as well...

What sway bars you have on the car, tjl IROC?

I was thinking of getting Hellwig sway bars from summit for it.
I haven't upgraded them yet.
springs, sway bar, torque arm, pan hard bar on the Xmas list

Anyone running anything other than Eibach Pro-kit springs?
Spring Rates?

The rear bar (1") is usually too much rear bar unles you lower the rear roll center. I had one on my car, and it was too much. I'd say get a set of GM bars and play with them til you find what you like. I have 36/24 on mine and like it. Good thing about the GM bars is they are cheap, pretty easy to find, and you know they'll fit lol.

You might be interested in reading (Spring rates for Moog 5660 & 5662 springs?)this thread about cutting the Moog replacements for certain heighs/rates. I'm considering doing this for my next 3rd gen. I might actually try it some stock pieces I have laying around to see if it'll improve my ride compared to the ProKit.

cutting springs seems like a bad idea
I just want to find a good set of springs with stock height at ~700 to 900 spring rate

It's not a bad idea if done correctly. I've read of competitive auto crossers and road courser who do it and reccomend it. As long as you don't heat the spring (therefore changing the temper) it doesn't hurt anything.
If you want a set of stock height springs with that spring rate, just get the Moogs listed in that page-5664 is 748, 5662 is 707. If that's not enough, find out what you'd need to get the same ride height with stiffer rates from an aftermarket supplier like SSS or ERS (Eibach Race springs).

I'm actually running cut 3/4 ton pickup springs in the front of my cp car and they seem to work awesome i was told from the cp guy i bought them from that they're about 1200 lb springs.

Weight jacks.

Then you can get CHEAP spring pairs in almost any rate you want to fine tune your ride.

You get the ride height you want..Can change it with just wrenches...And change your spring rate, up or down, cheaply buyt with good stuff.

I just get a straight answer on 155lb or 225lb rear springs...I have a set of both & am leaning towards using the 225lbs.

Yes that is enticing. For me it came down to either getting the Pro-kit and possibly a brake upgrade or getting the weight jacks. I obviously choose the Pro-kit and near future brake upgrade, but now I am questioning my decision. After driving more aggressively around some of the new neighborhoods nearby (houses haven't even begun being built but the road is paved and gravel free), I think the Pro-kit is a little soft. I think my car leans forward too much when I slam on the brakes and there is still too much body roll. I haven't fiddled around with the adjustments on the Koni's so maybe that will change my mind. I do have very rough roads around me and they Pro-kit doesn't feel much more rough than my bone stock springs and shocks did.

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As far as choosing your rear springs; I say go with the 225 and drive it for a while then put in the 155 and drive with those for a while. Compare notes and go from there. It isn't like the rear springs are hard to change... unbolt the shocks and PHB and slowly lower the rear end. Personally, I think the 155 will be fine for the rear. What spring rate do you have in the front? I almost wish I had like 800 or 850 for mine, but like I said, maybe adjusting the Koni's will make a big difference.

What brand of weight jacks do you recommend?

A lot of people go with Ground Control weight jacks.
http://www.ground-control-store.com/...tion.php/II=20

Mike

The only problem with that setup is...Its a coil over conversion. Not that is bad, no. That's actually a better setup, but $$.

But for a Weight Jack setup that fits the stock locations, look here....

http://www.ground-control.com/gccamcat.htm

What are your front rates? Bars? Tires? Shocks? Intended usage? I doubt you're going to to get a "straight answer". You're going to just have to try them. And that sucks because it means more track time!

I'd hardly say that coil overs are the better setup. They're awesome but with how much they restrict front tire size, which is already at a premium on our cars I'd rather go with weight jacks. I think the GC setup on the rear uses an odd size spring, a pigtailed one. There's another company that offers a rear kit that uses the standard 5" diameter race spring that makes it easy to replace and get new cheap rates. Let me look...

EDIT:
Rear; http://www.pitstopusa.com/detail.aspx?ID=23985

Driver/occasional autocross track time (no road courses here & I don't care about drag racing...over too fast!)

My bars are the stock WS6, 36mm front/24mm rear, might go down to a 21mm or 23mm in the rear...
275/40Z17s front, 285/40sZ17s rear...
dunno about my shocks really...whatever were on the car 3 yrs ago when I bought it, but I KNOW they aren't stock & not worn out

I'm hoping to get my rear Snypers widened to 11" & put 315s on, next year.

Unless you can specifically identify the shocks, I'd just presume they were parts store monroe replacements. Do you know from spring rates? It sounds to me like 255 would be WAY to stiff for you.

I was on the phone with GC the other day.The Price of $459 is right for our cars.
It a KIT 4 corners with springs. The picture is just of 4thGen parts.

The 2nd Link Is an OLD website when they sold front and rear separate. He said they just sell a KIT now. $459 as listed here
(Coilover Conversion kit, 82-92 Chevrolet Camaro/Firebird Weight Jack
Adjustable height spring kit, in stock location, not a true "coil-over")
http://www.ground-control-store.com/...tion.php/II=20



This is the info I got when asking about my '92 vert. 90% Street. 10% 1/8th mile and gonna hit beaver falls / nelson ledges maybe 1-2 times a year when they have open track day. That being said heres what I got..

1st Guy wasnt to sure on 3rdGen stuff because at 1st he recomended a 500#f and 350# rear.

I questioned him on why he came up with them #' ans his response was 350 in the rear because of the setup. (383lt1 with a turbo setup) and though a stiffer rear spring would keep it from squatting way to much on the street/auto-x with the Power the car should be making..

when I mentioned iroc/ws6/1le springs being more the 500# front he said he wasnt sure and transferred me to I think Jeff who knew more about 3rdGens.

He recommended a 800# front and a 200# rear for my vert, but that was his opinion coming from an aggressive driver as he said he was. He till said 800# front and maybe a 175# rear. With 36mm front say bar and dropping down smaller then my 24mm rear a little.

Hope this helps anybody reading this.

now my only concern is the type of rear spring GC uses with the pigtails vs the all star rear setup. Not like IM gonna be changing the springs a ton and feel I'll prob be fine with the 800/200

Pretty stupid to only sell a 4-corner kit. What happens when somebody needs just 1 replacement corner? Or needs the front or rear only?

I already have a rear pair & I'm not about to buy all 4 corners, when I only need the fronts.

looking around more link this came up.

http://www.daymotorsports.com/produc...-JACK-ASSEMBLY

Might help ya out. Then get front springs from hoever you want.