The +/- 1" diameter rule stands afik (which helps those of us with staggered diameters). You also get +/- 6mm on offset, you'll find a lot of "prepped" "street" cars running 5mm spacers to add a bit of track width and stay legal.

 

I did write to the SEB and they responded that indeed, a Grand Touring in '07 and '08 had 18x9F and 19x10R and regardless of if the car has the Rays v.2 rims, I could go with aftermarket rims in those sizes and be legal for Street.

 

06-08 GT's got the V2's. But to run the GT size wheels you have to have a GT trim or convert another model to GT spec completely.

 

Exactly, but the '07 and '08 have the HR, so a few more HP.

 

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