You don't want to run too big of a differential between the front and rear tire otherwise it will understeer like a pig.

I ran 255 fronts / 305s rears on Michelin Pilot Supersports and it was the perfect size & balance. Remember, Michelin Pilot Super Sports run about 10mm wide so in reality they were more like 265/315. More than enough rubber

 

New Wheels and Tires on. New Springs from Stuart at Velocity. Went with Michelin Pilot Supersports 245 fronts and 295 rears. Aggressive stance and no issues.