Front & Rear Springs
 

I'm looking for both the front and rear spring for my 94 Top Flight with 22,000 miles. The front spring delaminated in the center section and the rear has a 1 inch fracture all the way through. The parts are 17997093 Front and 17999322 Rear, and, of course, both are discontinued. The aftermarket doesn't seem to offer the front one. Any ideas or recommendations will be appreciated.
Thank you, Joe

Re: Front & Rear Springs
 

Joe, is it the same part number as a 90 or 91? If it is I may have both. That is if I didn't leave them in Michigan.

Re: Front & Rear Springs
 

Robert,
Thank you for your quick response. Unfortunately, 90/91 are different part numbers from 92/95.
Thanks again,
Joe

Re: Front & Rear Springs
 

Joe, just curious what spring code you have in the car right now.

Re: Front & Rear Springs
 

Correct.

Both springs are unique to ZR-1's.
Some were removed by those that changed to Coil overs and may be floating around.

If safety is a concern, and it should be, get any of the C-4 springs that are even remotely close to the rate of the ZR-1 spring.
Refer to Hib's chart at the Corvette Action Center

If judging is the concern do not dispose of the code tag from your existing spring, as that likely will be the only way to evidence a "correct" one.

These springs typically fail from the vehicle being tightened with a strap too aggressively when on a flatbed or a trailer.

The spring is not robust enough to handle being flexed the wrong way in those situations.

I have never found a new correct ZR-1 replacement spring.

But, things change.

Good luck!
:cheers:
Marty

Re: Front & Rear Springs
 

Stingray67,
Thanks for responding.
The rear spring is RHY. I can't see the front marking, but the NCRS manual states FSM.
Joe

Re: Front & Rear Springs
 

Marty,
Thanks for responding.
I'll be patient.
Joe

Re: Front & Rear Springs
 

Joe,
I also have a '94 that has a standard coupe HA code spring in it. And the car is sitting about 2 inches too low up front. I just bought an FHA code spring from Mirrock and will be installing it at the end of the month. FSM code springs are like hens' teeth. I also found an older ZR-1 Registry post from Marc Haibeck who said he has only ever seen FHA code springs on ANY ZR-1 he has ever done. That's why I was OK trying the FHA code. I'll let you know how it works out.

Not worried about the rear spring, mine is RHY as well and it sitting about right, ride height wise.

Re: Front & Rear Springs
 

Looking forward to hearing from you.
Joe

Re: Front & Rear Springs
 

Good news. I was able to pick up the correct springs from Marc Haibeck.
Case closed.

Re: Front & Rear Springs
 

Congrats, post some pictures of the ride height when you get it installed please. That correct ride height is what I'm chasing.

Re: Front & Rear Springs
 

Thank you.
There is a predetermined shim arrangement for ride height adjustment based on the color coding on the spring. The Shop Manual shows them.

Re: Front & Rear Springs
 

Can you measure the unsprung height for me? (peak of the spring down to the ground)

Re: Front & Rear Springs
 

I'd be happy to. I won't actually have the replacement springs until some time next week. And I'll be traveling Wednesday through Sunday. So I'll get back to you as soon as I can. Please be patient.
Joe

Re: Front & Rear Springs
 

Do you have good photos of the paper labels on the springs for other years? I have reproduced the front and Rear stickers for the 90 ZR-1 that have passed NCRS judging at Nationals. Front is AA with PN 17988598 and Rear is NYR 14065899.

Re: Front & Rear Springs
 

Stingray1967,
The front spring is FHA and the overall height at the apex is 8 inches. See the attached photos and a copy of the shop manual page for the front spring.
Joe

Re: Front & Rear Springs
 

Joel,
I have no labels for the springs.
Sorry,
Joe

Re: Front & Rear Springs
 

Thanks musuraca!! I'll have to measure mine now. Interesting that you received an FHA code.

Re: Front & Rear Springs
 

Joe, thanks again for the measurement. Mine is 8" as well (FHA code). Still hoping to get it in the car next weekend.

Re: Front & Rear Springs
 

Stingray1967,
Good luck. I'll be doing mine next week too.
Joe

Re: Front & Rear Springs
 

Stingray1967,
I got both springs installed, and now the front of the car is sitting at least an inch higher. It seems to be too high. I think I'm even seeing a slight slant upward in the front. Please let me know how yours turned out.
Thanks,
Joe

Sent from my SM-G950U using ZR-1 Net Registry mobile app

Re: Front & Rear Springs
 

At the risk of stating the obvious. Have you driven it since installing the springs? The springs and suspension need to settle after installation. Needs to be driven to do that.
H
:cheers:

Re: Front & Rear Springs
 

Thanks Joe, the spring install took about 4 hours. I had a group of guys helping, and a local car guy who runs a shop provide the space. Immediately after installing, the car was sitting higher than I wanted. I took the shop owner for a blast up to 7,000 RPM on the freeway, and when we got back it is was sitting PERFECTLY. I know the ride height is probably too high for some of you guys, but for me it is perfect.

A huge thanks to one of the local MN ZR-1 guys (Matt) for lending his Saturday, and to the NCRS guys, and to the shop owner, Eric. For non-ZR-1 repair work, check out https://www.ericsrepair.com/ if you are in the Twin Cities area.

-Chris

Re: Front & Rear Springs
 

Looks good. Mine is about the same. A little high for me, but OK.

Re: Front & Rear Springs
 

Joe, does the front sit higher than the rear now? Mine did initially, before I drove it a bit.

Re: Front & Rear Springs
 

Yes, just a bit. I've driven about 40 miles. I hope it drops a little more, but I'm not sure a composite spring will change much. I'm satisfied now because I know it's correct, and not fractured like the old one.

Re: Front & Rear Springs
 

Good deal. Enjoy the car! I put mine away for the year the day we swapped the spring. New tires and alignment happening next year as opposed to this year. I didn't want the car sitting on brand new tires over the winter. Better to have it sit on the old tires.