These are for people who have the ground control coilovers. I need to know the size of the rear springs. I need to know the inside diameter/outside diameter and the length of the springs.

Thanks dudes...

 

They're the standard Eibach race springs, 7" long.

 

Alright, well I couldn't find anything. I always search before posting.

Do you know the inside and outside diameter?

 

It depends, are they 2.25" or 2.5" ID? Both are common Eibach sizes. There should be a part number on the spring that'll tell you the rate in lb/in, the ID in inches, and the length in inches. Then all that's left is to get out the calipers to measure the wire diameter.

 

This is why I posted this in the 3rd Gen forum. I asked for someone to measure them for me. If I knew what the ID was then I wouldn't have made this thread .

 

Lupe, I have the GC setup and just measured the front springs. Sorry, but the front wheels are off, and the back's still on the ground...

Anyhow, they are 2.5" OD with about 7/16" wire diameter, so the ID should be about 1-5/8. I imagine the wire and ID will change a bit with rate, but I don't know that for sure. I measured 500 lbs/inch springs.

 

Inside diameter is only 1-5/8 ? That seems really small.......... hmmm

Thanks for measuring !

 

Yeah, I called eibach and the ID is 1.88 . The part number for the 100lb springs is 0800.188.0100 . I'll probably go with those.

 

^ Those are 8" long.

If you are using those as suspension springs, watch out. I tried 2.5" dia, 8" long, 250 lbs/in ERS springs on the back of my car, and they would coil-bind on bumps.

-Max

 

I know they're 8 inches long. My car is raised as high as it will go anyhow so an extra inch or less won't hurt anything.

What do you mean by coil bind?

 

Coil bind is when the spring compresses to the minimum lenth possible, when the individual coild touch each other, hence coil bind.

 

My car is pretty light, I doubt I'll have a problem with that.

 

Looking at this, the 150 LB spring might be a better choice like Crispeed said. They have a nice little charts toward the bottom.

http://www.competitionplus.com/2004_11_18/springs.html

 

Those are the WHEEL rates that they're reccomending since they keep talking about Mac struts, which give about the same wheel rate and spring rate. The FD has a high motion ratio front suspension (~0.6?), meaning a 150lb/in spring will in effect give a wheel rate of below 100lb/in.

 

That chart gives me a general idea. My FD isn't stock you know, 4 link, solid axle etc. etc. etc.

 

You should setup the suspension so that coil-bind is not possible before the suspension hits the bump stops, IMO. Otherwise, I think you will coil-bind the springs at some point, no matter what the car weighs. If you coil-bind, you will hear a loud BANG and instantly lose a lot of traction at the corner with the coil-bind.

The 2.5x8" 250 lbs/in Eibach ERS springs have a lot of coils, which makes their fully compressed length pretty long. I think that was the problem, moreso than the springs being soft. The stiffer springs I replaced my 250s with have slightly thicker wire, but several fewer coils, and so have a shorter fully compressed length.

If you get bind, you could use different springs or use longer bump stops. Unlike coil-bind, bump stops are (should be) soft and progressive, so they won't BANG or result in a surprising loss of traction.

-Max

 

I'm pretty sure that my suspension will bottom out before the coils will. There isn't much room for travel.

I'll take a look at it. I opted for the 150 lb springs.

Thanks.