Steering Wheel Center
 

I recently had my Miata aligned by a reputable shop and one that is really familiar with Miatas. However, when driving I am finding the steering wheel is offset from center nearly 3 degrees, which I understand is considered within spec.

The weird part is, they allowed me to sit in the car, and so, I held the steering wheel to "my" center for the duration of the alignment. I had marked the center with tape and pen marks prior, and so it was a simple to replicate the center I wanted.

Other than the steering wheel being off-center, there is no pull, tracking issue, or drifting (other than the expected road crown). The car tracks fairly straight.

Thoughts, not withstanding machine calibration error? Worn bushings perhaps? There does not seem to be any play with tie-rods or bushings when I try and twist the front wheels that are jacked up in the air.

2004 MSM
Stock suspension and wheels

Final Alignment Settings (printout):

Front Caster: 5.0 (both sides)
Front Camber: -1.4 (both sides)
Front Toe: 0.00

Rear Camber: -1.2 (both sides)
Rear Toe-In: 0.05 degrees (both sides)

SAI: 12.8/13.3
Included Ang: 11.4/11.8

Adjust the tie rods evenly, but opposite, directions. One flat at a time. If the wheel point left, left wheel in 1 flat, right wheel out 1 flat. Drive the care between adjustments until perfect.

Or just take it back and have them do it.

The toe adjustment won't effect any other setting. Let me take that back, the toe change will change with the ride height or you in the car, so if they reset it, the car should be in the same weighted condition as before. If you adjust them evenly, it won't matter.

Yes, I understand how to "fix" the centered-ness, but would that not mean the fronts won't be aligned to the thrust line angle?

In any case, my main curiosity is why steering wheel center might get offset even though the steering wheel was set correctly during alignment.

You aren't moving the tires, you're moving the steering wheel. All you're doing is moving the internals of the rack 1/4 turn to one side or the other, which rotates the steering wheel.

Because tires are rubber :)

Maybe you should have had a V8 before you went for the alignment.