Track camber: arms vs coilovers

[AltLogic]

I’ll measure my track width later today with my toe plates. I believe I have read that the rear performance brake rotors could cause the rear track to be 6mm less than the non performance rotors. If you have the performance rotors that would explain the 17/64”. I don’t have them so it might be an apples to oranges comparison if you have them.

BTW my next recommendation was going to be set about 1 degree negative camber in the rear and see what happens.

 

[beastmode13]

I need to come up with a way to allow the tires to turn freely then will be attempting a string alignment. Probably going to get some small plexiglas sheets or something and sandwich some grease between them, then roll a tire on top.

Graphite powder might work better. Just a thought.

 

[destructure00]

I’ll measure my track width later today with my toe plates. I believe I have read that the rear performance brake rotors could cause the rear track to be 6mm less than the non performance rotors. If you have the performance rotors that would explain the 17/64”. I don’t have them so it might be an apples to oranges comparison if you have them.

BTW my next recommendation was going to be set about 1 degree negative camber in the rear and see what happens.

I do have the performance rotors, and 6mm is within 1mm of what I measured, so that would make sense.

Graphite powder might work better. Just a thought.

Grease worked ok last night, I had to be careful powering the car onto the plexiglass sheets lol. First time I did it, it shot the upper sheet out from under the tire. I'll keep graphite in mind for next time.

 

[destructure00]

Went for a short drive on the freeway earlier. I think it feels better? I wasn't able to take a flyover at speed, but the straight line I think feels more planted and less wiggly than before. Need more seat time to be sure.

I now have a very slight pull to the left, which I think makes sense given the toe out on left front and toe in on right front. I haven't noticed before today either because I wasn't paying attention or maybe the big toe-in on the rear was masking it.

Anyway, crossing my fingers this helped some...

 

[AltLogic]

I checked my RWD car and I get the following to the nearest 1/32”:
The rear track is 3/16” less than the front. I have the OEM non-performance brakes, tires and wheels that came with my car. I think you would need someone with a performance model to compare track width, but at least my car and your car both have slightly less rear track width.
Bonus info: I have 1/32” toe in rear and 0 front toe. Close enough to my desired 0/0 for a street driven car.

 

[dsgerbc]

My Performance had about 1/4" wider front track width in the front last time I re-aligned after messing with FUCAs and LCA bolts.

 

[destructure00]

I checked my RWD car and I get the following to the nearest 1/32”:
The rear track is 3/16” less than the front. I have the OEM non-performance brakes, tires and wheels that came with my car. I think you would need someone with a performance model to compare track width, but at least my car and your car both have slightly less rear track width.
Bonus info: I have 1/32” toe in rear and 0 front toe. Close enough to my desired 0/0 for a street driven car.

Thanks for confirming! I think I'm going to shoot for the same toe numbers...already got 1/32" in the rear total last night, will adjust front to zero sometime soon.

 

[destructure00]

Went for another test drive. The straight line squirming appears to be gone. Yay.

It took me 3 laps but I finally got a chance to take the freeway flyover at speed again too (damn slow cars). Still got traction control and the weird jumpy feeling. But looking at the flyover, it's a flat or maybe even slightly negative camber ramp. I'm thinking now that the traction control is causing the weird jumpy feeling, not the other way around. I haven't felt it or seen TC kick in anywhere else, and in fairness I don't think I ever took this ramp at speed before messing around with the alignment.

So I'm calling one problem solved, and the other problem a non-problem. Still need to get the front toe dialed in, but I'm happy with the rear results so far.

 

[destructure00]

Got the front toe dialed in to zero this morning. Car drives great.

 

[AltLogic]

Glad to read the issue is resolved! And, the track with differential for the performance model is confirmed by @dsgerbc

 

[destructure00]

My Performance had about 1/4" wider front track width in the front last time I re-aligned after messing with FUCAs and LCA bolts.

I missed this post, looks like you and I posted at the same time and I never saw it. Thanks for sharing your numbers.

 

[destructure00]

Well the car tracks straight and feels good but I'm still having issues with traction control kicking in on the street when it's not really necessary. Started a new thread here
Traction control activating on interchange ramps and cloverleafs. Alignment or software?

 

[DrZoidberg]

@MountainPass
Another local auto-x victory with my MPP fucas, coilovers and camber arms! It was a domination on a short course, with over a second on the rest of the competition. Tesla torque earns the early lead and the MPP parts let you maintain it.