Offset control arm bushings - caster change amount

[hokejka]

Hey guys I just threw my rims on. Big rims and big tires but nothin that has not easily been run before. 17x9, 245/40. 22 offset and 12mm spacer. fender cut out.

My front tires hit the wheel well.

I am running offset control arm bushings.

I read through the stickies and it seems they effect caster (make it more positive) but no one talks about exactly how much. Im guessing I am missing almost 3/4" to an 1" of clearance. Could such a small offset in the control arm bushing translate to that touch more room from change of caster?

Is there any other way to move the wheel back to make more room?

The fenders are cut out in the pic so its a little hard to tell but if you look at the front I am about 1/2" from fender. It somehow just clears that but then hits the wheel well inside.

[Som]

I haven't done this on my E30, but on my '98 E36 M3, that looks about how much my wheel moved when I put the offset Treehouse lollipops on. On that car, I would touch the liner at full lock, but that's about it.

I ended up switching back to centered bushings because I'm vain and didn't like how it looked to have the wheel so far forward. Plus, even the full lock slight rubbing bothered me.

There's a thread on here, I believe, that goes over all the combinations of model year vs control arm vs bushing types. I'm guessing you need the centered bushings, or the offset control arms to match.

I don't know of a way to move the wheel back "slightly" though. Not saying there isn't a way, I'm just unaware of one.

Som

[Som]

http://www.rtsauto.com/e30-control-arm-bushing-upgrades-also-applicable-to-e36-comprehensive-guide-on-control-arm-bushings/

(posted by "noid" on here... the thread is actually about 10-15 down from this one right now)

[hokejka]

Thanks for the reply man! As far as I read the caster can be advantages in higher speed but at low speed not so much, so its a give and take. Im totally open to going back to center bushings. Do you think the centered bushing would move the wheel back that much where it would clear no problem.

I haven't done this on my E30, but on my '98 E36 M3, that looks about how much my wheel moved when I put the offset Treehouse lollipops on. On that car, I would touch the liner at full lock, but that's about it.

I ended up switching back to centered bushings because I'm vain and didn't like how it looked to have the wheel so far forward. Plus, even the full lock slight rubbing bothered me.

There's a thread on here, I believe, that goes over all the combinations of model year vs control arm vs bushing types. I'm guessing you need the centered bushings, or the offset control arms to match.

I don't know of a way to move the wheel back "slightly" though. Not saying there isn't a way, I'm just unaware of one.

Som

[hokejka]

read through whole article. Great literature

[Som]

That's how it worked for me, but on my '98. I added the offset bushings and didn't realize how drastically it would move my wheel. That article says that offset bushings + '95+ control arms would be a bad combination, since the '95+ control arms already change the geometry for added caster.

That said, on an E30, after re-reading that article, it sounds like offset bushings should result in a normal wheel position because that would be the right match for your control arms.

So, is there a chance the control arms on there are a '95+ version? Maybe check out the part number on it?

Som

[jntar]

I just switched from offset to non-offset for that reason. 16x9 et5 was hitting my bumper and inner fender. I no longer have the issue with the new bushings. I dont have a copy of my alignment print out, but I went from 10.1* of caster down to 9.2*. Hope that helps.

[hokejka]

Som: I am almost positive that the arms are e30 arms. I will check when I get a chance.

jntar: can't believe 16s hit even with the offsets. I just ordered my centered bushings. I got the 1996-1999 m3 ones as they should be stiffer but reasonable on price. What kind of tire combo were you running? Do you have plenty of clearance now? aka do you think with centered bushing on your car 17x9s would fit w fat tires?

[jntar]

Som: I am almost positive that the arms are e30 arms. I will check when I get a chance.

jntar: can't believe 16s hit even with the offsets. I just ordered my centered bushings. I got the 1996-1999 m3 ones as they should be stiffer but reasonable on price. What kind of tire combo were you running? Do you have plenty of clearance now? aka do you think with centered bushing on your car 17x9s would fit w fat tires?

I'm running 225/45 ZII tires. I haven't noticed any further rubbing on the front area, but at full lock i do get a small amount on the rear inner fender now. I imagine you will end up with the same result.

[hokejka]

I'm running 225/45 ZII tires. I haven't noticed any further rubbing on the front area, but at full lock i do get a small amount on the rear inner fender now. I imagine you will end up with the same result.

I don't have fenders hehe

[petrolhead]

Changing to M3 style bushes moves the tire roughy 2cm forward. M3 bushes are more eccentric than, say, Powerflex purple eccentric ones.

-Jarno