Spring Rate Opinions

[Dave]

Opinions are like assholes, everybody has one.

I am getting ready to order GCs for my e30. This is going to be a playtime car only - so "streetability" is not an issue. BTW, I had H&R Race on my cabby and I found it to be quite tolerable on the street.

My purpose is CCA Driving Schools, NASA HPDE, and perhaps the occasional auto-x. Track use is the primary purpose.

What types of spring rates should I consider? the car will have full on urethane bushings and THR CABs. Also will be running camber plates, etc.

Shocks will be Konis. I am getting the "shorter" ones.

I am thinking 475/650, but need input form someone who knows more than I do - or at least those of you who like to pretend on the internet that you know more than I do.;)

[rwh11385]

you wouldn't be able to feel the car rolling much with the stiffer rates. you would be loading/unloading the suspension and not notice, and therefore be surprised easier and then spin the fuck out.

i wouldn't recommend it for a novice. just order waffleswaffleswaffleswaffleswaffles rates and change them up later. no need to run what i would on a race car.

people who drive big soft X5s can actually learn better to start because roll is apparant and they are rewarded for being smooth.

hell, charlie started out on H&R sports. . .
come to think of it, Alex started on friggin stock springs (auto-x)

[cgregory]

I am thinking 475/650, but need input form someone who knows more than I do - or at least those of you who like to pretend on the internet that you know more than I do.;)

I'll pretend---I've got much softer rates than that ~375/450 and they really suit my needs well. They're bareable on the street and do pretty well on the track. That said, if you don't care much about the street, I'd recommend even a bit higher than you said, at least in the front. I've only talked to a couple of E30 guys that track their cars and run a GC setup, but they were both running ~550/650, IIRC. They were both M3s though, so I don't know how applicable that is to a 325.

[e9nine]

Everyone has their own assumptions at trying out rates. If you want, contact me via PM and I'll run some options by you. This way YOU can figure out which set up YOU like best as others chip in their 2 cents.

As anything else it comes down to dedicated car vs dual duty car, auto-x vs HPDE, if you will try any sort of rallycross etc etc

I have tried 350/475, 600/800, 600/650, 450/575 with Koni SAs coupled with stock sway bars and an e30 m3 rear sway in the mix. Sadly enough I have not been able to try these setups in a truly professional environment besides autox.

I am no pro at this but have ridden in other cars and listened to the advise of many and tried their suggestions as well. I personally don't believe in Sways but I am still experimenting.

[Beej '86 325es]

This might not help because I have not taken my car on the track, but here's my $.02...
For street / autocross, I have run:
(keep in mind these are all linear springs, not barrel)

initally 350/450 (front seemed fine, so left it alone, rear was far too soft and caused coil bind that damaged trailing arms)

350/600 (better, but rear still didn't feel right)

350/500 6", 2.5"ID with H&R adjusters (sits higher, but rides tons better)

[Dave]

350/600 (better, but rear still didn't feel right)

What didn't feel right about the 600 in the rear?

[Beej '86 325es]

What didn't feel right about the 600 in the rear?

Sorry, that was a bit vague. They felt too stiff, but I knew if I went any softer I'd have coilbind issues. Probably not an issue if you're on perfect roads, but the Midwest has some rough streets. I just felt a longer spring was necessary. Ground-Control now uses the barrel shaped springs, and I hear there are no coil bind issues with those.

But as you can see with the rear lowered all of the way, it does sit higher than some people like.

[Mystikal]

you wouldn't be able to feel the car rolling much with the stiffer rates. you would be loading/unloading the suspension and not notice, and therefore be surprised easier and then spin the fuck out.

i wouldn't recommend it for a novice. just order waffleswaffleswaffleswaffleswaffles rates and change them up later. no need to run what i would on a race car.

people who drive big soft X5s can actually learn better to start because roll is apparant and they are rewarded for being smooth.

hell, charlie started out on H&R sports. . .
come to think of it, Alex started on friggin stock springs (auto-x)

There's good advice here.

Go with something like 375/475. Good balance, will still lean.

[Dave]

475/650 might not be where I start, but 3xx/475 won't be either.

Waiting for some input from one or two other people before I place that order.

[rwh11385]

not be where I start, but 3xx/475 won't be either

why not?

[Dave]

why not?

have some good input from some others that suggest that something a little firmer (though not over the top) would be better.

[Digitalwave]

Talk to Ground Control, I'd say that have a little more experience than most of the people on this forum.

[Dave]

Talk to Ground Control, I'd say that have a little more experience than most of the people on this forum.

I threw this out there because I had trouble getting through to GC when I had called - on hold for an unacceptable amount of time.

[2002maniac]

I run 400/600 in my 318is and have had it on the track twice with this setup. Even with uprated sway's (cabrio/m3) there is still body roll and I canl feel the weight transfer fine. I think 475/650 sounds about right for a track day only car.

[Dave]

Thanks for the input guys. I have my answer.