JDANNER

I'm researching springs rates codes for a C4. I'm looking for a break down of the 3 letter codes stamped into the spring so I can cross-reference those to the yearly suspension packages and Newton/millimeter values. Is there a published chart with all this info in one place? Many thanks…..

rodj

http://www.corvetteactioncenter.com/...usp_chart.html

There was another list with the 3 digit codes around but can't find the link.

69427

I asked the same question a year or two ago, but never got an answer. Hopefully the chart now exists, as it would be handy to carry around when looking at springs at swap meets.

JCD

no luck for me either, of course I've never bothered to check the FSM so that could be an easy find...

Slalom4me

Several threads on the subject reside in the C4 Tech archives.

Here are a couple, compliments of the Advanced Search feature

Springs & spring rates - how to identify?

CF Member JasonL's .xls chart
http://www.tubas.net/vette/spring-codes.xls

Peer review of JasonL's chart with comments from Z-07 freak
spring codes....who wants em?

Fiche scans of front/rear spring codes from carfiche.com. Z-07 freak
has stated there are errors in these docs but has not provided details.

http://www.tubas.net/vette/

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Slalom4me

Hib Halverson's revised version of his suspension chart.
'Hib updated this March 17, 2002.'
I have not looked to see whether this differs from the
version that appears at CorvetteActionCenter or
the html version that resides elsewhere in idavette.net.

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Z-07 freak

Damn straight.

Slalom4me

Yo. Howzit?

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JDANNER

Thanks for the info, I'm more frustrated now than when I started. From all the old threads and the new responses I'm no closer to finding the definitive answers to my questions. For what it’s worth here is my three bears story: I swapped out my FHB/NYU combo because it was too hard. The car was skating across the track, no bite on any kind of track surface bump, plus loose condition too. I then installed FSS/RHZ like I had on my 94 street Vette. Way too soft! I never considered that the racecar was hundreds of pounds lighter. Plus it sits up high like a 4x4, this even after multiple races. Getting you car in the air a few times (Hoosier Hill @ Grattan) aint goin’ to make a difference. That FSS spring just has too much curve to it. The rear spring RHZ is a great drag race spring, the *** end squats way down tons of forward bite but this exacerbates the already high front end to the point that the camber starts to go positive causing a wicked push. I’m looking for the perfect bed in between. I’d love to find out the spring rate for a FSK GM part#17997091 it’s off a 92-93 heavy-duty suspension (FE7). Thanks for the help. If I ever run into a complete trustworthy list I’ll post it.

Z-07 freak

FSK = 90.1

Slalom4me

FHA = 93.1

Common as dirt, this spring was used on:
- 88-91 FE1, FE7, FX3 coupes

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jon0108

NYU'85-88 HD FE7

NYU'89 90 HD FE7 excFX3

NYU'91-95 HD FE7

BMF'84 exc HD FE7

BMH'84 HD FE7

NYR '86 HD FE7

NYR '87-01 Soft ride FE1

NYR '89-90 HD FE7 w/FX3

NYR '92-93 Soft ride FE1

I found these on the web, dont know how accurate they are.

Slalom4me

Until someone provides demonstrable proof of error, use JasonL's
MSExcel spreadsheet - see link above.

It is well organized and well researched.

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Z-07 freak

I'm so sorry. I didn't realize the purpose of my life was to provide you with "demonstrable proof of error".

JCD

Apology accepted. Now that we've cleared that up...

Slalom4me

I wasn't necessarily talking about you.

But since you bring it up, Z-07 freak, as John Donne said: 'No man is
an Island, entire of itself.'

From 03-01-2004
Is this behavior of popping in to foment uncertainty your idea of providing
a Rosetta Stone on C4 spring codes and rates?

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JDANNER

I found a FHA at Contemporary Corvette boneyard in Bristol PA for $150. They did not have the FSK so I went with common the dirt spring. Picking it up tomorrow and if all is right with the world it goes in this weekend. I hope it’s really rated at 93.1 with not too much arch in it. I’d hate to waste money, effort & track time to find out I’m still off the mark. Can’t wait to compare it to the FSS and see how much flatter it is. Stay tuned…….

Slalom4me

If desired, use N/mm * 5.710 = lbs/in as a conversion factor

88-91 Coupe
FHB 115.5 N/mm = 659.5 lbs/in
FHA _93.1 N/mm = 531.6 lbs/in

92-95 Coupe
FSK _90.1 N/mm = 514.5 lbs/in
FSS _73.2 N/mm = 418.0 lbs/in

How much has the car been lightened? Have you considered
approaching forum vendors like VB&P, VanSteel or others about a
custom spring with a rate suited for your application?

Switching to coil-overs - more outlay than desired?

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JDANNER

The series I'm running in Touring Challenge for Corvettes requires that I run under the old Corvette Challenge rules and they state no coil overs. I need to run stock GM parts. Counting my fat *** after a race 3000lbs.

Van Steel

I listed the spring rates on all the Hyperco springs we offer.
http://www.vansteel.com/index.cfm?fu...&SubGroup=1950