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Discussion Starter · #1 ·
I'm thinking about having the toe-in adjusted on my car the next time it's in for service.

So far, I've read that increasing the toe-in reduces tramlining, and makes the steering less "nervous" at speed. True??

So my questions are:

1) How much toe-in should I do?
2) How long does it take at the dealer? Does this involve a full alignment, or just work on the front end?
3) How much were you charged?
4) Any adverse effects? (ie, increased tire wear, etc)

Also, I've noticed on windy days, cross winds seem to really affect my car on the highway. Will increasing the toe-in help correct this?

Thanks!
 

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King of Rear Clunks
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Although toe-in in front will help a bit with tramlining and wandering, don't expect miracles. Those two factors are more dependent on overall suspension geometry, with a good deal of that going to caster angle, which on most cars is not adjustable.

An extremely crude example is a shopping cart. The swiveling wheel wants to be behind the line of the pivot. Move the cart in the other direction, and the wheel will swivel to the other side.

I don't know what the caster angle is on a E46, but I'm willing to bet its enough that toe-in will not kill off tramlinging/wandering completely.

The car should come with some toe-in (I know mine did), so I don't know how much more I'd add. You'll start affecting other characteristics like tire wear and handling if you go too far.

And because this is an alignment task, you'll want the whole thing re-aligned if you do this.
 

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Discussion Starter · #3 ·
Kaz said:
Although toe-in in front will help a bit with tramlining and wandering, don't expect miracles. Those two factors are more dependent on overall suspension geometry, with a good deal of that going to caster angle, which on most cars is not adjustable.

An extremely crude example is a shopping cart. The swiveling wheel wants to be behind the line of the pivot. Move the cart in the other direction, and the wheel will swivel to the other side.

I don't know what the caster angle is on a E46, but I'm willing to bet its enough that toe-in will not kill off tramlinging/wandering completely.

The car should come with some toe-in (I know mine did), so I don't know how much more I'd add. You'll start affecting other characteristics like tire wear and handling if you go too far.

And because this is an alignment task, you'll want the whole thing re-aligned if you do this.
Alright, great feedback. I guess I'll just leave it alone then. Not that it's bad the way it is. I was more curious if increasing toe-in would have some kind of significant effect.
 

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My saga...

Kaz, Geomax-

You'd think that the toe-in question would be a simple one. After doing lots of research, I've come to the conclusion that its anything but. My car (325 w/ sp) had the steering retrofit done. The dealer told me they set the toe-in to the max allowable setting which they said was .4 total. That sounded high to me, and when I asked another dealer they said .25 total. If you look in the Bentley's manual it says .07 +/ - .09 total toe is the range for all E46 body types and suspensions (camber and caster ranges are different for the 3 types of suspensions-- xi, sp, and regular). I told my dealer to dial back the toe-in-- they claimed they did but "forgot" to give me the printout proving that-- or the roginal printout for that matter. So I have no idea what toe-in i'm running- but my steering has too much "slop" in the center that I attribute to the toe being too great. The car tramlines fairly often too- so I guess max toe-in isn't the magic bullet to solve that problem. The strange thing is that I don't recall my old steering / factory alignment doing that or having the slop.

So, like you I just want to find the "optimum" toe settings that will provide a balance between straight line stability and fast turn-in. I'm inclined to go w/ the factory settings. The only problem is that no one seems to know what these are. Since the Bentley's is the most concrete source I have, I'm inclined to believe that all cars come set to the "middle" of that spec which would be .07 total toe-in. I'm assuming the range is there to allow for different driving preferences. .07 toe would cause you to have slightly different left and right toe-in settings- I think this is what the factory does based on something i read a whilie ago--its supposed to help compensate for the road crown-- so ii think the right wheel gets more toe than the left. Of course, I've also read a bunch of stuff that says if the left and right toe aren't equal the steering will be off center. So who knows? I've also seen differing points of view as to whether to adjust the toe based on changes to camber or even tire pressure. And, whether the car needs to be in its "normally loaded poistion (150 lbs each front seat, 150lbs in back seat, full fuel tank)" to correctly set the toe. I somehow doubt that any dealer actually does that anyway. The bentley's only gives one range for all the suspensions (which have different cambers and casters), so its hard to know what the optimum toe is for each setting is or even if it matters.

From what i've read, the real goal of setting the car to toe-in is to achieve a toe neutral setting at speed. As the car's speed increases the wheels are pulled out (on a RWD) car. If you don't have enough toe-in, the car will toe out under speed and make it excessively darty. Too much toe in causes the car to remain 'toed-in' at speed which causes accelerated tire wear (as does toe-out), and vague steering, as wells as understeer in corners. This is the collective wisdom that i've culled together after reading about alignments in books and on the internet-- but each of these sources shed varying degress of light on the subject and often contradict each other.

Needless to say, all of this info has confused me to the point of indecision. I don't want to pay my dealer $100 a pop to try different alignment settings (along w/ the hassle of giving them the car for the whole day just to make this change each time). I've searched the web for home laser alignmetn gauges and "toe gauges", but the laser ones are atleast $700 and the manual ones seem a little inexact unless you're extremely anal. Ideally, I want to try the .07' given in the Bentleys for a week and see if I like it. I've been trying to locate a "good independent alignemtn shop" in my area but this seems to an elusive beast. I've asked the president of my BMWCCA chapter for one and recently received a possible choice. I'm going to contact this shop tomorrow and try to end this alignment odyssey. I'm also trying to figure out a way to find out what sp equpped cars come set at from the factory. Any ideas? Anyway, alignment is one of those subjects that the more you learn the less you know- and the less you trust some semi-skilled 20 year old "technician" to do it right. I'll keep the board posted if I find a "good" setting and am going to make sure to get the printout next time!
 

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Gosh - good thread. Just about when I was getting to really appreciate the retrosteer (got used to slow speed bumpsteer, i.e.) my steering seems to have loosend up in an imitation of my early April 01 SA rack. I did run over a parking curb lengthwise and I've been lurking whenever anybody posts about steering, etc. Is this like when you read a medical text and imagine that you have that disease. I wonder. How come I never noticed any of this during the test drive? I know. It was because I was not smart enough to insist on a freeway test. I think I might get another alignment when I get my first service in about 2 K. BTW, my car came from the factory misaligned somewhat. So we bugged BMW until they caved and gave a mere 325i a rebuilt rack with more feel and now we are still saying the steering is loose. This must drive them crazy. Not one day has gone by that I regretted getting a new $29000 325i. Except I do kinda like that Lexus SC470 or whatever it is. Scratch that - it most assuredly has no soul.
Michael Murphy and Blue Thunder
 
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