My stock rear springs are sagging over an inch and I was looking at replacing them all the way around. I don't really want any stiffer springs then what the car came with. The RPO on the rears ends in NL and the fronts in ZX. If anybody could let me know the rates on those springs it would be very appreciated. Thanks

Out of six different rates, your fronts are the second firmest, and your rears are third out of five. Here is what I'm going off of:
Front Springs
______________________________________________________________________
67 RS w/F41 Suspension
87 Z8 w/ FE2 Suspension

Prod# Code Service #
- - ---------------------------------------------------- (+) Highest load
rate
14029399 BZY 14029399 |
14029398 BZX 14029398 |
14029397 BZW 14029398* |
14029396 CDB 14029396 |
14029395 BXY 14029396* |
14029396 BXX 14029396* (-) Lowest load rate


Rear Springs
______________________________________________________________________
67 RS w/F41 susp
87 Z28 w/FE2 susp

Prod# Code Service #
- - ----------------------------------------------------(+) Highest load
rate
10018083 NNB 10018092* |
10018092 NNM 10018092 |
10018091 NNL 10018091 |
10018093 NNN 10018091 |
10032969 NYB 10018091 (-) Lowest load rate



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'82 Firebird, dead stock, 9 bolt disc rear, over 200,000 miles and still going strong, more to come...
http://www.spinfrenzy.com/stingerssx...easures.html#4

Thanks for the numbers but you wouldn't happen to know the actual spring rates. I was looking at getting some aftermarket springs and want something comparible. Thanks again

If you find out, please e-mail them to me. Thanks.

I seem to recall that IROC front springs were 450 lb/in rates... I bet rear springs are a bit less. I run 700 lb/in rates for the front now and it is a little firm. Good shocks help too.

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1984 z28 w/ a 357 cu in. monster engine which is looking like the posterchild for Edelbrock with the exception of the Holley 750vac... all the suspension stuff... 9-bolt posi disk is in...

-=ICON Motorsports=-

[This message has been edited by Biochem (edited February 18, 2001).]

The Iroc and WS6 springs were 548 pound springs. Stock base springs were 350 pounds. Dont know what the rears are.

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-Justin-
T-Top '86 5.0L LG4 700R4 WS6
T-Top '92 5.0L TBI 700R4
My '86 Firebird Homepage
The F-body Model Kit Pictoral Archive (updated 9/18/00)

There can be only one!!

Justin's right. I'm sure the IROC's are 548lb/in.