Stiff Suspension

[coupeowner]

I have the GC setup w/ the single-adjustable Koni's. I have 550/600 springs and the fat IE bars. For track days, I set the front bar to full stiff, and the rear fairly soft. For autocrosses, I remove a link on the rear bar (no bar), and set the front bar to full soft. Works for me. The track setup is pretty dialed in at this point. The autocross I have paid less attention to, but I can say that I could not get the car to hook up w/ the fat rear bar on the tight courses our autocrosses are on. Just my experience.

From what I understand, the SA Koni's are only good up to spring rates of 600-650. Don't take my word for it, but make sure you don't exceed what the shock can handle.

David
'89 325i

[rwh11385]

Trent, what are your rates?

I decided to go without rear bar most likely. I'm going to do one day of my HPDE with the rear stock on and then disconnect it and try it out.

The way I see it I want to be stable, and people like Jon Felton got ST bars and now his car likes to go sideways, etc, then I shouldn't even be upgrading to a m3 bar.

Plus, with GC's I can have my friend hopefully still have the hookup on ERS springs and get a pair for $80, instead of buying a M3 rear bar, some new bushings, some new endlinks, and possibly a reinforcement for the mounts if I want to. All the $$$ versus 80 (or 120)......makes more sense to counteract understeer by stepping up the rear rates rather than adding a bigger rear bar.

[Bryson]

don't ERS springs cost less than $80 directly from GC, Robert?

[rwh11385]

don't ERS springs cost less than $80 directly from GC, Robert?

last time I ordered a pair it was like $120 or something. They are $60 each or so. My buddy tried to be a parts supplier for a while and had (hopefully still has) a connection to get them $40 each spring.

[Mystikal]

$55 each from GC.

[rwh11385]

I think there are way too many people setting cars up too stiff thinking it is the bomb.

lowering springs. They are generally stiffer than factory, which may not be too much of a problem for some, but there are two schools of thought on springs. Some people believe that you should run the stiffest spring possible in order to be competitive. Others feel you should use the softest spring possible, without bottoming out.

Since the primary purpose of the spring is to keep the tire in contact with the road at all times, it stands to reason that the softest spring would follow the road more closely than the stiffest spring, which would bounce all over the place (ever see a back hoe drive? NO suspension - Infinitely stiff).

This is not to say that stiff springs don't improve handling - they do, greatly! But only on a smooth road surface, and remember, the smoothest road is rougher than the roughest race track.

Allowing your suspension to bottom out abruptly changes the way your vehicle is following the road. This is extremely dangerous since the car may not be in contact with the road anymore! If you have lowered your car such that the frame contacts the ground, you are inviting a disastrous skid.

http://www.geocities.com/g_wellwood/automotive/handling.html

stiffer isn't always better. the least stiff suspension that avoids bottoming out may be best.

but the r3v kids will always go for full blow race stiff suspensions though

[cwbaader]

Robert, you mentioned adding rear bar or stiffer rear springs to counteract oversteer...that is backwards. If the car is loose, soften the rear either by solfter springs or remove the rear bar. Chuck

[rwh11385]

if i said that, that was a mistake.

but i think my post says counteract understeer (from increasing the front bar or going m3 endlinks), not oversteer.