spring rates???

[xLibelle]

so you are going to toss the rear trailing arms?!?!

maybe a thought eventually, but first move is to put the springs and shocks together. most likely require tower modifications based on coil diameter.

im working on ways to drop the rear without increasing the camber but will eliminate room for stock location of springs.

[xLibelle]

I found a deal on some high quality springs that will all but fit a bmw ... lmao
600f and 425r - i thought this a suitable setup for a track car. (btw, the 425's will be relocated to accompany the rear shock's location)


(i will most likely have to fabricate perches for the front and in the rear... uhg, major remanufacture since thier dimentions are 13x5. hell, i might have to just toss them, but we wont know until i get them and under the car)

[Mystikal]

Even with a proper rear coilover setup relocating the springs outbard, 600/425 is way much of a forward bias.

[xLibelle]

really? you think? thanks for telling me NOW!!

actually, with the way the e30 suspension is setup, it should come out to approximately 575f/430r

please explain how this difference will be way too much forward - really, i have no idea. i think its on the conservative side based on set balances from manufacturers.

considering this 145 difference is a little much, how can i make up for it in weight distribution and swaybars? if what you say is true, moving weight to the front would be the idea, but these cars arent perfect anyway so i should be close on weight distribution w/o making a lot of fuss. and im not sure where to go with the sways after all this.

im shooting in the dark because no one replied so let me have it.

[cwbaader]

Spring rates depend wholy on chassis stiftness!!! That said, for a non caged car, I have run 900# front springs and 700-1100# progressive rears with Koni adjustables on the street without problems. The springs perse will not make your car ride harshly...that task belongs to the shocks---they contol spring travel and dampening...stiffer the shock, stiffer the ride, no matter what spring you use. After running a lot of different setups, talk to TC Kline about the single adjustable Koni kit they have...it will work very well street and track.

Another note, lowering more than about 1 1/2" in the front necessitates shortening the front strut tubes to prevent insert damage! Everyone, Turner, TC, IE, etc. will tell you their kit is the best available for your application...choose wisely. Good luck, Chuck

[Mystikal]

really? you think? thanks for telling me NOW!!

actually, with the way the e30 suspension is setup, it should come out to approximately 575f/430r

please explain how this difference will be way too much forward - really, i have no idea. i think its on the conservative side based on set balances from manufacturers.

considering this 145 difference is a little much, how can i make up for it in weight distribution and swaybars? if what you say is true, moving weight to the front would be the idea, but these cars arent perfect anyway so i should be close on weight distribution w/o making a lot of fuss. and im not sure where to go with the sways after all this.

im shooting in the dark because no one replied so let me have it.

The primary physical property of a car that dictates spring rate balance is weight distribution, and the E30 really is damn near 50/50, meaning you'd probably want almost the same wheel rate front and rear. A stock E30 also does understeer in general (lift-throttle anitcs notwithstanding), so if you'd deviate from the 50/50 spring setup you'd probably want to lean towards a rear bias.

Fixing this issue with sways or the horrible idea of moving weight forward (are you serious?) are poor band-aids, really. x" ID Springs are cheap and plentiful.

[golde30]

Another note, lowering more than about 1 1/2" in the front necessitates shortening the front strut tubes to prevent insert damage!

is this true even if u have the struts revalved to match the springs rates on the coilovers? i havent heard of any1 doing this on their e30, and plenty of ppl here have their cars down more than 1 1/2"...?

[xLibelle]

x" ID Springs are cheap and plentiful.

can you run this by me again?

[IS]

The linear springs used with GC coilovers, for example. Its a standardized size which works in many applications through the use of upper and lower hats.

[xLibelle]

im talking about the cheap and plentiful part!

[2002maniac]

im talking about the cheap and plentiful part!

Getting used springs from racers is the best way to do it.

[Nick325is]

is this true even if u have the struts revalved to match the springs rates on the coilovers? i havent heard of any1 doing this on their e30, and plenty of ppl here have their cars down more than 1 1/2"...?

He is referring to shorteing the strut housings to increase suspension travel when you lower the car. When the car is lowered the amount of suspension travel is decreased. I brought the shortened konis with my GC kit so that in the future I could do this modifcation.
The shortened konis come with a 4 inch spacer pipe that goes in the strut tube. This is because the konis are 4 inches shorter. So in order to increase travel you need to cut the strut housing a couple of inches and then shorten the spacer by the same amount. This will lower the car though so you have to raise the springs some to compensate.


Nick

[JRKOUPE]

[QUOTE=golde30]is this true even if u have the struts revalved to match the springs rates on the coilovers? i havent heard of any1 doing this on their e30, and p


its true...but not always neccessary. GC says its a good idea to shorten the tubes to maximize the set up(which includes suspension travel) and to get the most lowering possible . But many have done w/o it ........ GC says it is not mandatory. Its really only needed to maintain suspension travel on a severely lowered car.