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Posted by: pek771 Jan 18 2024, 05:54 PM

Hi all,
I’m trying to find out how long the rear springs were from the factory. I think my old springs are shot; the shocks were. I have new Bilsteins. The old springs were like 12 1/2 inches long and I did not need a spring compressor to get them out. And the bottom spring perch was all the way up. It appears there are 15mm between the rings on the shock body.
So I just want something that’s gonna work, but I don’t know what the original was. What I’m really trying to figure out is if I have room on the shock absorber for any old spring.
I had a really lot of negative camber like almost three degrees. I don’t think the PO played around with it too much but somebody may have. Maybe the PO to the last PO. I’m thinking that the negative camber is from the springs being worn out and the shocks being worn out.
This is all much easier to do with no batteries in the way.

I haven’t even gotten around to looking at the front yet.
TIA
Pat

Posted by: brant Jan 18 2024, 06:45 PM

If I remember
Your electric

Scales would help
But you have to spring for your new weight

Posted by: Superhawk996 Jan 18 2024, 07:22 PM

Not uncommon for aftermarket, higher rate springs to be shorter due to higher rate and usually lower ride height than OEM.

You’re either going to have to weigh and do some math or potentially waste money with trial and error approach.

With semi trailing arm, camber and ride height are interrelated. 3 degrees is an awful lot of camber. Is that measured camber or just a wild guess? How many shims are in it? With that much camber I would be expecting no shims to be present and that the rear ride height is sitting very low.

Dampers (shock absorbers) have absolutely zero effect on camber.

Posted by: pek771 Jan 18 2024, 07:54 PM

2100 pounds.. same as it was just about.
Weight on the proform scales:
2004 total, no driver, hoods, targa top, glass, one battery is out of the front (55 lb)

this is the first iteration, Now that I know how to work the scales and can get the car to stay on them, I can do the suspension.
FR 450
RR 508
FL 484
RL 562

I think the car was lowered. From what I can tell, car was hit once and fixed. PO likely got a good deal on it, and used it in the very early 80s. After that, jackstands for a long time. It was sprayed blue, and the gearbox was A-F-M-S-X. (I took out the X and put in a ZD, along with a Quaife torque biasing differential). Judging by the gearing, it suggests someone sort of knew what they were doing screwed around with the car. I don’t think the PO did it.

Anyway, I need to know about the setup of the rear suspension.

Posted by: Superhawk996 Jan 18 2024, 08:38 PM

If you are that close to stock weights, why not just use typical aftermarket (like 100 lb/in), use the rear damper adjustable perch to set ride height, shim appropriately to get camber to spec?

I’m simplifying here, not knowing what torsion bars you have up front and assuming that your primary interest isn’t handling.

Posted by: Superhawk996 Jan 18 2024, 08:51 PM

Forgot I had this in my files - pilfered from somewhere on this site. Can’t vouch for accuracy or authenticity but looks to be plausible and correlates to what I’ve read from others that OEM spring rates were 50-60 lb/in.

This is basically the information you originally asked for

Posted by: pek771 Jan 19 2024, 05:40 AM

Thanks @http://www.914world.com/bbs2/index.php?showuser=22428 ,
I ordered some 100 lb Eibach springs from 914rubber, along with some new rubber bushings for the suspension. I will fiddle around with the ride height. I’d like to get back to stock height.
Pat

Posted by: rgalla9146 Jan 19 2024, 07:57 AM

Never saw that chart before.
I knew there was info such as date of manufacture, color of paint and
number of paint marks but had no idea there was so much more.
Is there an explanation of colors ? I've seen yellow, red and green.
2lb. increments !

Posted by: pek771 Jan 19 2024, 08:53 AM

I have no paint marks on the springs, Only a tape measure.
I will document what I find, for posterity.

Posted by: aturboman Jan 19 2024, 09:44 AM

For reference here is a set of original 6 springs with the factory paint marks saved during restoration.

Posted by: pek771 Jan 19 2024, 10:42 AM

I think the springs were black, once long ago. Now they just look like they were glass beaded

Posted by: rgalla9146 Jan 19 2024, 04:04 PM

OT
Robert have you seen a date on those springs ?
I've seen it stamped into metal near the end of the coil.
It would be neat if we could verify that the various colors had meaning.
We've both seen yellow on 914 6s