Alignment for E30 M3 offset CABs + some low

[Panici]

Hey guys,

I've put on some offset E30 M3 control arm bushings and my alignment is noticeably off.

Last year I put on a set of H&R Sport springs, and this year added thinner spring pads and E90 drop hats. I never did get an alignment when the lowering springs went on.

The car isn't "MAD HELLA TYTE FLUSH SLAMMED" or anything, I estimate a total of 1.8"-2" drop in the front. (I never did measure)

Car is my summer/fall DD (although I do hope to get a track day in at least once a year.)


TL; DR
What is adjustable alignment wise front and rear?
Any suggestions as to settings?

[Todd Black 88]

Toe front, and nothing in the rear.

That's all that's adjustable on the stock e30 suspension.

[Panici]

Toe front, and nothing in the rear.

That's all that's adjustable on the stock e30 suspension.

That's all that seemed adjustable as I've been working with the suspension. I was hoping there was more to it then that!

Any recommendations for front toe settings?

[Dirty325ix]

Well don't forget that the whole idea behind the m3 control arm bushings is to change the geometry of the front suspension and the fact that it is lowered would change everything even more (probably should have gotten it aligned when you lowered it)
From my experience the m3 control arm bushing make the wheel sit noticeably farther back in the wheel well than with stock bushings

Don't the m3 bushings add a bunch of caster to the wheel therefore increasing high speed stability

And toe should be kept within bmw specifications nothing fancy (.11"-.19" inwards ) the shop that does the alignment will know

[Panici]

Well don't forget that the whole idea behind the m3 control arm bushings is to change the geometry of the front suspension and the fact that it is lowered would change everything even more (probably should have gotten it aligned when you lowered it)
From my experience the m3 control arm bushing make the wheel sit noticeably farther back in the wheel well than with stock bushings

Don't the m3 bushings add a bunch of caster to the wheel therefore increasing high speed stability

And toe should be kept within bmw specifications nothing fancy (.11"-.19" inwards ) the shop that does the alignment will know

It depends in which direction you install the offset bushings. The usual way moves the front wheels forward, and adds caster, as you've said.

I would bet that the local alignment shops don't know what the BMW specs are (hence this thread).
I hate bringing my vehicles to any shops, I don't trust them.

[Dirty325ix]

Well now I'm learning something new

[Dirty325ix]

Well now I'm learning something new....good to know

[Panici]

Bumping this thread. My friend with an E36 M3 suggested that I run Zero toe upfront.

What do you guys think?

[DRTSRFR]

By lowering the car you have added static camber. Stock is 1 degree negative. Lowering 1.5" will add roughly another degree.

If the car is primarily driven around town. Zero toe will reduce inner tire wear.

For spirited driving, adding about 1/16" toe out will improve turn-in, but increase inner tire wear if the car isn't seeing somewhat aggressive cornering.

[Panici]

If the car is primarily driven around town. Zero toe will reduce inner tire wear.

For spirited driving, adding about 1/16" toe out will improve turn-in, but increase inner tire wear if the car isn't seeing somewhat aggressive cornering.

I'm not super concerned with tire wear. But I do a lot of highway driving, and I don't want to end up with something twitchy.

I do like responsive though.

[BrokeFastGarage]

Unfortunately twitchy is responsive. That's why you always hear to put in as much caster as possible. The centering effect of the caster stabilizes the front end and let's you run aggressive toe out to get good response on turn in. Without adjusting caster you can't have your cake and eat it too.

[BoxDriver86]

Caster is a measurement of suspension angle, or how far tilted your suspension is from front the back on axis. The M3 CABs increase caster to increase high speed stability. Caster has almost no impact on tire wear but will increase steering effort. Increased caster will, as said above, make the driving a little more twitchy.

My car is excessively low, with -2.15 degrees of negative camber up front. I run the stock recommended toe and have no tire wear issues up front. I do like 0 rear toe (with the added adjustments) for lowered cars.

[Panici]

I should update. Had the front toe set to zero, and it's nice to have my steering wheel straight.

Car drives well. Good balance between turn-in and stability.


The rear alignment isn't looking great, I think mostly in part to all of the original bushings. That'll be next summer's project.