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[LiM3y]

I recently hit a pot-hole hard enough to require a wheel alignment for my 08 M3 Sedan. The BMW shop used generic specs for a 3 series to complete the alignment (attached). If there is an expert out there who can comment on whether this is appropriate, or if different "M3" specs should be used, I would appreciate the help. I have read conflicting comments on-line. (the handwritten notes on the left). The car is essentially for street use, so specific track specs are not necessary.

Thanks in advance for your help.

[achenator]

I would think that M's would have a special alignment due to all of the neg. camber.

[SenorFunkyPants]

Wheel_Alignment_US.pdf
This is the USA spec for the E46 M3....probably not much use except for giving an idea of the general alignment for this type of sport suspension.

[smmmurf]

Looks like the specs that you got are pretty good; little toe, even caster, even camber. Should be great for street driving... you have a touch of negative camber in the front (good) and a little more than that in the rear (also good). If you start adding extreme negative camber, you can wear your tires out faster and have suboptimal grip under braking.

[SenorFunkyPants]

Instead I would suggest that the car a little needs more front negative camber....I'm betting that the proper specs for his car would show something similar to the E46 M3 spec...gives better turn in and better grip under heavy cornering load at the front with no downside under braking once the tyres have worn in to the new alignment.

[smmmurf]

Originally Posted by SenorFunkyPants

Instead I would suggest that the car a little needs more front negative camber....I'm betting that the proper specs for his car would show something similar to the E46 M3 spec...gives better turn in and better grip under heavy cornering load at the front with no downside under braking once the tyres have worn in to the new alignment.

True. However, the difference between -.7º and -1.0º or even -1.2º static camber is negligible on the street and probably also pretty hard to detect at a casual track day. It's certainly not worth another trip back to the alignment shop in my opinion. I think the most important thing is that the car is aligns evenly and well within spec after hitting that pothole.

[SenorFunkyPants]

Originally Posted by smmmurf

True. However, the difference between -.7º and -1.0º or even -1.2º static camber is negligible on the street and probably also pretty hard to detect at a casual track day.

I think for this particular car thats fair comment, but there are cars that do react noticibly to quite small changes in front camber and toe. Nevertheless its still worth having the correct alignment specs rather than the specs from a different car even if the differences may not noticible in the short term.

Originally Posted by smmmurf

It's certainly not worth another trip back to the alignment shop in my opinion. I think the most important thing is that the car is aligns evenly and well within spec after hitting that pothole.

I guess so...myself I would make the trip back once the dealer has the correct M3 alignment spec if it varied significantly from the generic 3 series spec they used.