Ever since I had my wheels/tires installed I've had slight vibrations (steering wheel and seat) at certain speeds (70-80mph). I've taken it back to the shop once and I believe they performed a static balance only (maybe dynamic) but it got better. However, I still have a little bit of vibration at those speeds. My wheel and tire spec's are posted below and I have approx. 39psi in each tire.

For those that have modified wheels and tires, how is your ride? Also, has anyone ever had a dynamic and force load balance? If you're in the SF Bay Area, let me know what shps you've been to. FYI, Motorsport Techniques is the only shop that has worked on my car. I plan on taking it back today (if possible).

 

I have 22's on my gs300 and it rides ok but I also have that vibration and my alignment is off a bit to. I have never had an alignment after changing just the wheels and tires but I guess that I need one.