I guess, high G's (I do drive it at M3 speed or faster), high body roll, and crapy cambernate328Ci said:
How can you roll over that far?
Mine don't roll off the tread at 40psi on 16" wheels :dunno:
I have 17 X 8 inch rims with 235/40 S-03's.
At the autoX both the front and rear roll over to the seam beyond the tread, but before the sidewall. I would think I need more PSI, but it seems to handle so well, also I would think 44 PSI should be more than enough (44F, 40R). I have another autoX Sunday (YEAH TWO IN ONE WEEKEND!!!), and for now I plan to go with it as is.
When I drive around town I can see that I never roll over this far, so it is only at the autoX.