Whats the FE2 Stock spring rates for the irocs?
does anyone know what the other
spring rates are
FE1
F41

did we ever get code FE3 = SUSPENSION SYSTEM, SPORTS?

 

my iroc came stock with NNL and BZX springs i would like to know the spring rates for these, iv searched and found a list of springs with part numbers,
would i want to match the fronts to the backs? by getting NNM's?
or would it throw the hole connering of the car off?
i know the fronts will have more wight on them witch when wighted down they should be matched to the backs?
i will have have alum heads and water pump lighten front end
i plan on cutting 1" off mine
i have a bunch of mods coming up i want to conner like a madman!
-------------------------------------------
14029399 BZY 14029399 -------------- (+) Highest load rate
14029398 BZX 14029398 **
14029397 BZW 14029398
14029396 CDB 14029396
14029395 BXY 14029396
14029396 BXX 14029396 -------------- (-) Lowest load rate
-------------------------------------------


-------------------------------------------
10018083 NNB 10018092-------------- (+) Highest load rate
10018092 NNM 10018092
10018091 NNL 10018091 **
10018093 NNN 10018091
10032969 NYB 10018091 -------------- (-) Lowest load rate
-------------------------------------------

 

anyone?

 

Well i found the rates for mine? but its on a forme and not an iroc

front
BZX 14029398 ’87 WS6 Formula 611lb/in
Rear:
NNL 10018091 '87 WS6 Formula 155lb/in

does anyone know what the NNM rate is?

 

I know this was posted a couple a months agao but I have 2 more springs to add. BXA and for the rear npk
off an 83 v6 berlinetta
Thanks Randy

 

Looks like you found the measured rates that I posted in a few places…

F41 fronts are BXW and work out to be 397lb/in.

Don’t know about the others that you’re asking about… If someone get get me one or give me more info (even exact measurements and I can calculate it)…

 

BTW, these are all numbers and tags of springs from my garage... I think I have more, but missing tags so I can't attribute what they came from

 

Got the tag numbers from my build sheet.

 

I'm bringing this thread back from the dead as a Christmas present to myself.

Seriously though, I noticed that on NEEDforSPEED's car that the coils on his car are not the same spring load rate for front and rear. In other words, the rears from factory are one notch below the fronts and I have seen this a lot on other F Bodies.

I'm curious as I was checking out the parts numbers on the coils that I bought years ago from the Chevrolet parts counter. I told the guy that I wanted to build a 1LE clone of sorts and wanted the strongest coils. He sold me Part #14029399 BZY fronts and Part #10018090 NNM rears which are one notch below each other as far as load rates go on the chart above. Is this done to compensate for the front and rear weight of the car? If it is, doesn't make sense as the stock coils on my LT were the same part number front and rear according to my build sheet (Part #10027653 NUZ coils).

 

BUMP

 

No way.

The springs on the 2 ends of the car are COMPLETELY different in terms of end shapes, wire diameter, overall diameter, length, and rate. Fronts are subject to about a 2½:1 lever arm for the force of the car's weight acting on them (i.e. the force on them is about 2.5 times the car's weight, but they only change length about .4 as much as the car moves up and down) while the rears are 1:1.

F a bunch of "build sheet". Go physically LOOK AT your springs. I think you won't have much trouble figuring that out.

Stock, the front rates are all in the 300 - 500 lbs/in kind of range, from luxo barge (Berlinetta/SE) to performance (IROC/TA). Never seen any stockers that have rates like Need posted, but I'm certainly not going to say that he's wrong, only that I've never seen them. Stock rears are in the 120 - 150 range.

Good replacement ones such as Moog 5662 or 5664 for the front have rates in the 650 - 750 lbs/in neighborhood. Good rears such as CC635 or 5665 have about a 165 rate at stock ride height.

 

And a year later....

The original springs on my car are long gone. I had made the mistake in the mid 90's to heat them up to lower my car. That's why I got the new one's I mentioned above.

All LT's in 1987 ended up getting the stock suspension from the standard sport coupe. Guess Chevrolet didn't want to use the soft suspension that the Berlinetta had anymore.