Spring Rates

[Demps]

I have a few questions and observations. My experience is mainly with '95s but I've worked on or helped others work on other years.

Some observations:
1) I think the plant used what ever parts they had at the time to put on cars.
2) I have '95s with different spring rates--I'm assuming at least as they have different markings.
3) I have seen different spring rates on other years.
4) The '95s became more of a GT car than the '90 Sports car.

Questions:
1) What do the spring rate codes mean.
2) What are all of the spring rates, codes and correlation between the two?

I have seen "FHA 1-3" and an "FHA 1-5" fronts. What are the rates?
I have also seen "RHY 1-1" and "RHY 1-3" rears. What are the rates?

Is there any difference?

Ted

[rgfllamas]

Took this from another website, maybe it will be helpful.



Try this data.

C4 Spring Code Chart

compiled by Hib Halverson
?2007 Shark Communications

Preface Notes:

1) GM had two RPO subsystems during the C4 era. There were engineering RPOs and marketing RPOs. What consumers knew as Z51 or Z07 was actually a combination of the FE3 (96) or FE7 (84-95) HD suspensions with other performance-related options. Some GM parts data refers to FE3 or FE7. When those RPOs are listed, it refers to cars optioned with either Z51 (84-91, 96) or Z07 (92-95).

2) In MY89-91, Selective Ride Control (SRC), which many refer to by its RPO, FX3, could be ordered in combination with Z51, however, a little-recognized production change which always occured in those MYs when those two RPOs were ordered together was a downgrade to base level (FE1) springs, front lower control arms and stabilizer bars. In those MYs the only conditions under which FE7 was present were; 1) if the car was ordered with Z51 and without FX3 or 2) it was an 90 or 91 Corvette Challenge car.

3) For MY92-95, FX3 and FE7 was added. A new RPO, Z07, was released for this combination. For MY92-95, FX3 was, also, available as a stand-alone option.

Coupe, front

HMZ 84 w. Z51
BMB 84 base, 85-87 with w. Z51
HKX, HMP 85-87 base
FHA 88-91 base, 89-91 w. FX3&Z51
FHB 88-91 w. Z51
AA 90-91 w. ZR1
FSS 92-95 base, 92-93 w. FX3
FSK 92-95 w. Z07
FSM 92-95 w. ZR1
HA 94-95 w. FX3
22173028 96 base
17999032 96 w. Z51

Convertible, front

HMN 86-87
FHC 88-91 base, 89-91 w. FX3
FSR 92-95 base
JA 94-95 w. FX3
22173029 95 w. FX3
17999031 96

Coupe, rear

BMF 84 base
BMH 84 w. Z51
NYR 85 base(?) 86-93 base, 89-90 w. FX3&Z51, 90-91 w. ZR1
NYU 85-91 w. Z51, 92-95 w. Z07
RHY 92-95 w. ZR1, 96 w. Z51
RHZ 94-96 base

Convertible, rear

RCA 86-96
22112254 94-95 w. FX3

[FULLPWR]

I manage a division of a Spring manufacturing company here in houston.
We have calibrated Spring Testers we use everyday and can inspect and document the rates for as many springs as you wanted to test and tag & identify each with the rate results. NO CHARGE !!!!!

Let me know if that's something you may want to do sometime.
If so ship them to me and I can do it the same day I recv them and ship em right back to you that same day.

could also re-shotpeen them too. and mag particle test em too.




Luis

[Demps]

Thanks Ken and Luis. Luis great offer!

I found the link I was looking for...My post is geared toward tying it all together.

http://zr1netregistry.com/ZR1_suspension.htm

Are the sub-category [# dash #] (e.g. 1-1) relevant? Are the three letter designation (FHA) relevant? Do ZR-1s have different springs amongst like years; different years?

Ted