Kerrrslammed - GC Coilovers complete!

[Bimmerman325i]

Spring rate was mentioned, 570lb. On a GC kit I have no idea, I think the issue is the amount of droop travel of the shock, not bump travel. Since the spring isn't held captive under droop by anything, the spring shouldn't be the limiting factor.

[MisterMiniS]

So, I have been informed of two main routes.

1) Giant rear springs and no rear bar
2) Not giant rear springs and a beefy rear bar.

I agree with Bimmerman and that I want as much travel as possible to keep inside rear on the ground, yet be as stiff as possible. I know that I can get different rates, but for now I have shock adjustability and can add, remove, change sways.

I think I will get a lot of feedback saturday as to what the car needs. I am going to look at that Vorschlag e30 and read up on that.

[blefevre]

So on a normal coilover kit (GC) does the rear actually bottom out from the shock or is the spring the limiting factor? I didn't see them mention the spring rate of the rear.

[Bimmerman325i]

http://vorshlag.smugmug.com/photos/323833840_k5uog-S.jpg

http://vorshlag.smugmug.com/photos/321486129_49ALg-S.jpg

Basically, added a tender to the coilover spring in the rear.

[blefevre]

"A dual coilover+tender spring set-up was added to the rear to allow the spring to remain seated at this extreme droop travel. "

More info?

[Bimmerman325i]

This post, specifically: http://forums.bimmerforums.com/forum...&postcount=276

OP, that car's build is a good one to mirror. The Vorshlag guys have done a considerable amount of testing on an E30 autocross car, and all the suspension tricks will be helpful for you.

[Bimmerman325i]

Ah, taller/softer springs with remote dampers will do it. I probably cant do that without raising the cars height or some fab work though.

Ride height I don't think went up much, and there wasn't any fab.

Read through this thread, it's interesting to see where they started from (ast 4100) and ended up (way custom 4100/4300 hybrid): http://forums.bimmerforums.com/forum...d.php?t=858257

[blefevre]

Ah, taller/softer springs with remote dampers will do it. I probably cant do that without raising the cars height or some fab work though.

[Bimmerman325i]

McLaren laughs at sway bars!

But yes, that is what I thought....but how do you get lots of travel from 800+ rear springs?

Ha, they didn't on the McF1, and they have a system that acts similarly on the MP4.

How VS did it was remote res damper, so that the damper body itself had more available travel before hitting the internal shock bits combined with taller springs and IIRC tenders as well. Worked really well.

[blefevre]

McLaren laughs at sway bars!

But yes, that is what I thought....but how do you get lots of travel from 800+ rear springs?

[Bimmerman325i]

Confused. So he should run soft springs and no bar? I get the idea is to avoid rear wheel lift, I just am confused on what you are saying.

Yea, that was stream of consciousness.

He wants the softest possible stiff springs and bar combo, if that makes sense. Stiff springs + bar + more travel is what I'd aim for, sways are good things. Honestly though, I'd clone Vorshlag's e30 autocross suspension build as much as I could. That setup was pretty choice, and since OP is running race tires, he won't have as many compromises (no LSD, etc).

[blefevre]

Confused. So he should run soft springs and no bar? I get the idea is to avoid rear wheel lift, I just am confused on what you are saying.

[Bimmerman325i]

I dont think 875 is stiff enough for no rear bar. Keep it stock.

A lot of people run no rear bar but stiff springs on E30's.

Yes, but the reason why is to avoid rear wheel lift in corners, and they're essentially slapping a band-aid on a punctured artery; it's not the right solution.

E30 rear needs more travel than common performance shocks give-- that's why Vorshlag used their triple adjustable remote reservoir 4300s on their 318is autocross car. Problem most people do is use a good shock that has a very limited travel range, combine it with stiff springs, and then take out the rear bar because it's imitating a dog pissing. A big part of the solution is getting more travel in the rear.

[blefevre]

I dont think 875 is stiff enough for no rear bar. Keep it stock.

A lot of people run no rear bar but stiff springs on E30's.

[Bimmerman325i]

Beef up the front, keep the rear bar soft but present.

Why do you want to remove the rear?