Please check my alignment settings - pulling slightly left (I think)

[Brian0473]

Just lowered the car on Eibach springs and drive it about 50 miles to settle it in before a 4 wheel alignment.

Here is the after report which appears normal to my amateur eyes.

The car feels like it might be pulling very slightly to the left. Does anyone see anything in the alignment that might cause this?

Thanks in advance for any help.

[SenorFunkyPants]

did they check the corner weights?

[Malek@MRF]

If it hasn't been noticed already, its because you have more negative camber on the driver side in comparison to the passenger side and that is why your car pulls.

One other reason could be is that the steering wheel is not truly centered and the Ackermann geometry is rearing its ugly head and causing the pull.

But I will strongly correct the front camber differential, cross camber on the front should be as close to one another as possible.

[Brian0473]

Originally Posted by SenorFunkyPants

did they check the corner weights?

We never discussed this so I assume they didn't. I guess I always thought that was reserved for a "performance" or race alignment...

[Brian0473]

Originally Posted by Malek@MRF

If it hasn't been noticed already, its because you have more negative camber on the driver side in comparison to the passenger side and that is why your car pulls.

One other reason could be is that the steering wheel is not truly centered and the Ackermann geometry is rearing its ugly head and causing the pull.

But I will strongly correct the front camber differential, cross camber on the front should be as close to one another as possible.

Only because you mention it I wonder if the installation of my new Performance steering wheel could be contributing. Although I installed it a couple of weeks ago and didn't notice any pulling until now. It also has a notch that I felt like made the install pretty much fool proof. Is there any cause to pull it off and reseat it?

[Malek@MRF]

Originally Posted by Brian0473

Only because you mention it I wonder if the installation of my new Performance steering wheel could be contributing. Although I installed it a couple of weeks ago and didn't notice any pulling until now. It also has a notch that I felt like made the install pretty much fool proof. Is there any cause to pull it off and reseat it?

Steering wheel install is completely unrelated to what is going on here.

[Brian0473]

Originally Posted by Malek@MRF

Steering wheel install is completely unrelated to what is going on here.

Thought so...thanks for the quick reply!

[SenorFunkyPants]

Originally Posted by Brian0473

We never discussed this so I assume they didn't. I guess I always thought that was reserved for a "performance" or race alignment...

Twice I have had issues with cars (not M3s) "pulling" even after an alignment check.
One was due to incorrect corner weighting and the other was due to the power steering rack not being centered when the alignment was done.
I can't see why a little cross camber difference would make it pull but what do I know.

[kenwelch]

If you look at the lower page Secondary Readings your SAI side to side difference maybe causing the problem. The Alignment technician should have noticed this and let you know.

This is a link to an earlier post about damage and SAI readings (watch the video):
http://www.m3post.com/forums/showpos...43&postcount=6

There is always the chance that SAI was not measured correctly.

I will see if I can locate a specification, but the left to right split seems too large.
Found the specs here:
http://www.m3post.com/forums/showthread.php?t=192175

You will notice that your camber difference is not beyond the factory allowable of 30' (or .5 degrees) side to side.
The spec sheet does not provide a SAI specification, but looking at other forum members readings in the link will confirm that you have a problem with SAI if the technician did the measurement correctly.

[kenwelch]

I found a good diagnostic article that you might also find helpful:
http://www.m3post.com/forums/showpos...5&postcount=10

Your problem is that the Left to right SAI and Included Angles are incorrect. You could also use the chart in the article for the diagnosis of your problem. Use the chart on page 6 under the MacPherson Strut Suspension.

[Brian0473]

thanks kenwelch! I'll take a look and share with my tuner to see what he says.

[Brian0473]

So the issue ended up being that somehow one corner of the alignment machine was tilted by 1/16" which caused false readings.

Thanks again to all who tried to help! I actually learned a lot about alignment!

[kenwelch]

Originally Posted by Brian0473

So the issue ended up being that somehow one corner of the alignment machine was tilted by 1/16" which caused false readings.

Thanks again to all who tried to help! I actually learned a lot about alignment!

Thanks for the follow-up of the problem.
Is the slight pull now gone?
Is there a chance that you could post the final reading with the alignment lift level correction?
I am interested to see how much 1/16" turn -plate height difference changes the SAI and Included Angle readings.

[Brian0473]

Originally Posted by kenwelch

Thanks for the follow-up of the problem.
Is the slight pull now gone?
Is there a chance that you could post the final reading with the alignment lift level correction?
I am interested to see how much 1/16" turn -plate height difference changes the SAI and Included Angle readings.

I'll post a follow-up next week. My tuner is having his alignment machine corrected before we try again.