It seems to me that the tires are a little small for the wheels on the car. Also they offer no curb protection as they do not extend past the edge of the rim.

Can larger sizes be used without altering the dynamics of the car in a negative way?

Will PSM function properly with different tire sizes on stock rims? I don't want to effect the front/rear diameter ratio which could effect the sensitivity of the PSM.

Also, on a similar note....can I bring the wheels out a bit with the 5 mm spacer kits that are available and will that have any detrimental effects on the handling and ride of the car or effect the longevity of the suspension/wheel bearings?

 

Would be interested in the answer to this as well.

 

I dont have any techincal answer for you but it could be the brand of tire you have might have less of a rim protector band than some other brands, a Pirelli P Zero has less of a band on the Turbo than the Pilot Sport does on the GT2, just different style tires and brands, the GT2 runs 315 30 18 in the rear but it is fitted on a 12" wide wheel and a 235 40 18 up front on a 8.5" wheel, I would say stay stock sizes but maybe go with a different brand that suits what you are looking for.

 

Well I slapped on some BFG DRs which are certainly wider than spec at 315/30 and 245/40. If you have stock suspension you will get some rubbing up front... 5mm spacers are a good idea. Kevin rolled my rears a lil' but I think we were ok anyways.