Adjustable front control arms? Adjustable tie rods? Please help me!!

[Nadeemp8]

Hey folks,
Looking for some advice in an area I don't know much about. I have an M3 dropped on H&R Sport Springs on factory EDC struts with 15mm spacers on the fronts. Have had the car aligned by a very reputable shop a few times (SoulSpeed) and they have it aligned within specs. I have noticed uneven tire wear on inside shoulder of the front tires. I don't track the car often (1-2x per year) and am looking to maximize my tire wear on the fronts. Currrent tread depth is 7/32 on the front, but inside shoulder is almost smooth.

I have installed GC camber plates, but with these fully adjusted I can only add more negative camber, which doesn't help my uneven wear. The shop is saying only way to add positive camber to even out wear would be to add additional hardware like SPL adjustable LCA's, otherwise there's nothing else they can do.

Question is, do I need to add adjustable control arms to dial in a bit of positive camber? Do I need adjustable tie rods to combat bumpsteer? What the hell should I do?

[Nadeemp8]

Man, I get no love here! So another item I was looking into is Bump Steer. I'm not finding much on the forums about this with the F80's, and would think on a conservative drop (H&R Springs) that wouldn't be as much of an issue, but could that be the reason for my inner tire wear since car is aligned within spec?

[DLag30]

Originally Posted by Nadeemp8

Man, I get no love here! So another item I was looking into is Bump Steer. I'm not finding much on the forums about this with the F80's, and would think on a conservative drop (H&R Springs) that wouldn't be as much of an issue, but could that be the reason for my inner tire wear since car is aligned within spec?

I would have thought with GC camber plates, you'd be able to dial out some of that negative camber. Do you have Pics if the camber plates installed on the car? It would be interesting how maxed out they are

[Nadeemp8]

Originally Posted by DLag30

I would have thought with GC camber plates, you'd be able to dial out some of that negative camber. Do you have Pics if the camber plates installed on the car? It would be interesting how maxed out they are

camber plates are fully maxed out, can only add more negative camber.

[fanatic1]

Not sure how helpful this is as I spend a fair amount of time on the track. -2.7° front camber but zero toe and even wear across the tire. Most of the extreme wear that you describe is from incorrect toe (or rubbing).

You’re right front with 0.18 toe shouldn’t be enough to cause excessive wear.

I did go to a second alignment rack and found significantly different readings, you might give this a try.

[Nadeemp8]

Originally Posted by fanatic1

Not sure how helpful this is as I spend a fair amount of time on the track. -2.7° front camber but zero toe and even wear across the tire. Most of the extreme wear that you describe is from incorrect toe (or rubbing).

You're right front with 0.18 toe shouldn't be enough to cause excessive wear.

I did go to a second alignment rack and found significantly different readings, you might give this a try.

hmmm...strange! the .18 toe was after I installed the camber plates but before the alignment. toe was .04 on both front after alignment. I've had the car aligned by 3 different places now, with each giving me same results! not sure what else it could be as I havent heard of anyone else in the same boat as me

[Keebin]

i run all the adjustable arms from spl including flca. mine currently are set to almost the stock length of the oem arms. flca really just correct for roll center along with added negative camber gain and track with on extension. if you wish for less negative camber then you would want to raise the car up to factory.
if you decide to go with the flca be prepared to spend money on the full spl setup, spl does not tell you that in order for you to run the arms you will need the caster rods at minimum and while your there you should replace the tie rod ends. seem really extreme for positive camber gain for lowering springs. Are you sure the car has never been hit?

The tie rod ends will help with bump steer but i dont understand how you could have so much with just lowering springs.

has anyone one looked in to one of the arms because bent, and does the car drive straight when letting go of the wheel?

[Nadeemp8]

Originally Posted by Keebin

i run all the adjustable arms from spl including flca. mine currently are set to almost the stock length of the oem arms. flca really just correct for roll center along with added negative camber gain and track with on extension. if you wish for less negative camber then you would want to raise the car up to factory.
if you decide to go with the flca be prepared to spend money on the full spl setup, spl does not tell you that in order for you to run the arms you will need the caster rods at minimum and while your there you should replace the tie rod ends. seem really extreme for positive camber gain for lowering springs. Are you sure the car has never been hit?

The tie rod ends will help with bump steer but i dont understand how you could have so much with just lowering springs.

has anyone one looked in to one of the arms because bent, and does the car drive straight when letting go of the wheel?

Car hasn't been in any accidents, that I'm sure of. I would think one of the past places would have let me know if any parts were bent when doing the alignment, as I've had 4 alignments done in the past 20k. One of the front struts was replaced as well as the RF steering knuckle, otherwise everything else is factory except for the springs and has about 36k on it.

Car tracks straight as an arrow, don't have any steering issues on or off track and it feels great when I've driving it!

One thought that comes to mind is that last few alignments have had my toe set as close to .00 as possible, and I know DINAN recommends total toe of .17 +/-.07, and I've been at .01 and .08. Since 95% of my driving is street and highway I'm thinking I don't have enough positive toe (toe in) set on the front. Technically I don't have any toe out, but by adding positive toe maybe that would compensate for the inner wear and help me get more even wear? Any thoughts here?

[TheBreeze]

It's something else causing your wear issues. 1.8-2.0* of front camber should not be causing excess wear, especially if toe is at 0. I run 2.3* 0 toe front, 1.5* 1/8 toe-in rear, and get totally even wear. I'd check bushings and maybe even take it to a different alignment shop. The place I take mine to uses the BMW specific wheel mounts instead of the generic wheel mounts that a lot of shops use. The BMW mounts are designed specifically to fit into the little holes present in the stock wheels (around the lug area).