[Avet4]

Alright guys, I'm posting this because after searching thru so many alignment threads it's only confused me more.

My car is completely stock except for the Turner Sways. It's got nearly all fresh ZHP suspension, therefore stock ride height. Yesterday I also finally changed the tierods too, so now I need an alignment, but until I can schedule one I need to set it myself to a comfortable setting. Since it's the weekend I don't know when a real alignment will happen.

I initially gave it too much toe-in during install and the ride was kinda scary, it would turn in way too aggressively, and even get stuck at the full lock position.

I re-adjusted it a few minutes ago so both front wheels are pointing nearly straight forward.

I'm a little concerned as to why it got stuck when it swung to full-lock. Could it be steering rack related? By that I mean that I centered the steering wheel simply by starting off the adjustments with the steering wheel centered and the wheels facing forward, before and after replacing the tie-rods. I didn't actually base it off any bolt on the rack itself.

There was some rotor-dust-shield rubbing, but that was probably cuz I bent the shield when hammering at the balljoint, I bent it back. Everything else is nice and snug.

I haven't taken it out for a drive yet to see how the turn-in is, but I wanted to clear up some questions I had beforehand.

One question I have is what adjustments does a stock suspension nonM e46 have? Obviously toe, but is there any caster or camber adjustment and if so from where? I thought it was just a rotating bearing on the strut tower.

Also, the reason I changed the tierods was cuz the old ones were seized and an alignment couldn't be done. Is there anything in the rear of the car that might also prevent a tech from doing a proper alignment?

More specifically, the ONLY rear suspension components that I DIDN'T replace are the RTABS. I'm not familiar at all what adjustments exist back there.

I'd appreciate any input on this.

 

[Avet4]

nothing?

 

[hummer]

nothing?

Front and rear toe and chamber are adjustable. Caster is not adjustable.

There is a pin in the front shock tower that must be driven out to adjust camber. Loosen the three tower nuts and adjust the camber. The RTABs are the only item I have replaced on my car in 164K. If you are over 50K replace theem. The RTAB carrier is adjustable for toe and the lower track bar has an eccentric for camber adjustment.

 

[Avet4]

Front and rear toe and chamber are adjustable. Caster is not adjustable.

There is a pin in the front shock tower that must be driven out to adjust camber. Loosen the three tower nuts and adjust the camber. The RTABs are the only item I have replaced on my car in 164K. If you are over 50K replace theem. The RTAB carrier is adjustable for toe and the lower track bar has an eccentric for camber adjustment.

Are the RTAB carrier and track bar prone to seizing up in the same way as the tie-rods? I just want to make sure these aren't gonna be problems before taking it in to the shop.

 

[LivesNearCostco]

No, not that I know of, but if you drive on salted roads (you're both in Taxachusetts), the eccentric bolt on the lower rear control arm (track bar?) could seize. The more common problem with rear toe is once the RTABs wear out, the rear trailing arm (RTA) can move in and out too much so you get rear toe changes while driving and your rear tires wear out faster. Also if you get towed and the tow truck driver uses your lower rear control arms to pull your car, they can get bent and change your rear camber. So if RTABs are worn, replace them before trying to align rear. If rear lower control arms are bent, replace before aligning rear.

Also, aggressive turn-in when driving is usually caused by having too much toe-out in front, not from having too much toe-in. BMW spec is for significant toe-in up front to promote straight-line stability. Aggressive track alignment might be for zero front toe. The crazy Autocrossers might set toe-out in front as AutoXers are rarely going in a straight line for more than 3 or 4 seconds.

Toe-in = / \
Zero toe = | |
Toe-out = \ /

 

[Avet4]

No, not that I know of, but if you drive on salted roads (you're both in Taxachusetts), the eccentric bolt on the lower rear control arm (track bar?) could seize. The more common problem with rear toe is once the RTABs wear out, the rear trailing arm (RTA) can move in and out too much so you get rear toe changes while driving and your rear tires wear out faster. Also if you get towed and the tow truck driver uses your lower rear control arms to pull your car, they can get bent and change your rear camber. So if RTABs are worn, replace them before trying to align rear. If rear lower control arms are bent, replace before aligning rear.

Also, aggressive turn-in when driving is usually caused by having too much toe-out in front, not from having too much toe-in. BMW spec is for significant toe-in up front to promote straight-line stability. Aggressive track alignment might be for zero front toe. The crazy Autocrossers might set toe-out in front as AutoXers are rarely going in a straight line for more than 3 or 4 seconds.

Toe-in = / \
Zero toe = | |
Toe-out = \ /

Thanks for the response. Luckily mine aren't worn or bent, so I'm certain I should be fine then.

What then is the recommended settings for a street car? Since I just got new wheels and tires I want the tires to last as long as possible.

They're unidirectional so if I have negative camber on all 4 wheels then there isn't any way to rotate them to keep the tire-wear even.

So would it be a good idea to keep the rears at zero toe and with a tiny bit of negative camber, and the fronts at a slight toe-in but zero camber? I feel like this way I could rotate them front to back to keep wear even, but would this have a mal-effect on handling?

 

[LivesNearCostco]

Edit: Cliffs--Use BMW spec for non-sports suspension but with less toe-in.

Long version:
From Bentley manual: Slight negative front camber (-0.33 degrees regular, -0.71 deg sport), medium negative rear camber (-1.5 deg regular, -2.0 deg sport), and toe in, 0.23 degrees total front toe in, 0.26 degrees total rear toe in. Will will give you decent cornering, good straight line stability, and somewhat fast tire wear, especially in back.

To maximize cornering performance, more negative front camber more negative and less front toe-in. Example: I used -1.3 deg camber and -0.12 degrees total toe-in up front. That's almost double the front negative camber but half the recommended toe-in. (Now I have -2.6 degrees front camber, but that's not optimal for street driving--it's a compromise for AutoX and track.)

Reduced toe-in reduces tire wear. In theory you could go to zero front toe and have even longer tire life, but the car will be less stable on the freeway. The E46 rear needs some toe-in otherwise supposedly it gets loose and unsafe. I reduced total front toe-in from 0.23 degrees to 0.12 degrees and did something similar in the rear.

See attached Bentley and TIS sport alignment pages. Note that many angle measurements are in minutes (') and there are 60 minutes in each degree, so 60' = 1.0 degrees; 30' = 0.5 degrees, and 15' = 0.25 degrees.