I want to buy new wheels and tires for my 2001 Mustang. Currently the car has 17" wheels with 275/40ZR-17 Falken tires. The wheels are 17x8 in the front and 17x9 in back.

I want wider tires in the back. Preferrably Nitto NT555 315/35s. I want Nitto NT555 275/40s on the front (I think).

I want American Racing Torq Thrust M wheels, but I don't know if I have the clearance for 18" wheels/tires. The car was lowered before I bought it. There is about 3"+ clearance from the top of the tire to the fender lip on the front and a little more in the back. Is this enough clearance for 18" wheels/tires? Or do you think I should stick with 17" wheels/tires?

Thanks!