hi Odie, I've just measured my spare Alpina 7x16 'E30' wheel. The hub-hole is ~57mm, & the offset is slightly more than 29mm. These guys fit the car "like a glove" and I've never had a rub. My suspension is rather stiff, and the tops of the wheel-arches are 24" (front) and 23-7/8" (rear) above the ground. Decent (heh!) amounts of 'negative camber' also help to keep the tops of the tires away from the wheel-arches, I've also tried to keep the f & r toe-in v. minimal, tho' this makes the car rather twitchy to road-conditions. It's been hard to find the best setup. But I've only ever used 205/45-R16 tires - my overall tire diameter is ~23-1/4". Your proposed 225/55-16 diameter will be ~25-3/4", so you'll need more clearance to the arch-heights, and perhaps a larger offset as well. IMO the 225/55-16 tire will be too wide & too tall for the car. Even w/ the 15" track-wheels, I only use a 205/50-R15 tire. The 225 width will give too much lateral grip, & the 55 sidewall will be too rubbery for precise turn-in. One prob I've had w/ both my +1 (track) & +2 (street) wheel/tire combinations is that the front is too grabby & the rear is too loose, when the tire-pressures are equal. So I generally run w/ 8psi (track) & 5psi (street) higher pressures in the front tires, which throws a bit more weight to the rear & makes the car much better-balanced. My point is, that making the change that you propose will *radically* change the handling abilities of your car. Having lots of grip, you'll be able to turn in at higher speeds, w/ much less 'push' than you're accustomed to. This'll be fine, so long as you keep the power on through the turn - but if you're ever (unexpectedly) req'd to lift throttle after a turn-in, you'll be traveling faster & will find the rear-end to be lots lighter than you're used to! This can be a prob in traffic, or in the rain.