Application: Autocross, local events only.
Tires: 275/40/17 Kumho Victoracers, two heat cycles and are shaved to 4/32's.
Rims: 17" OEM Ford non-bullitts, the $195 option polished rims.
Pros? Cons?

 

Is that rim a 17x8 or a 17x8.5? Pinching 275's onto an 8" wide rim is really pushing it, and some shops won't do it.

That said, 275's on a 17x8 or 8.5 rim is going to feel pretty squishy. You will lose all crispness during turn-in, but you will gain in overall grip. For strict stock classing, though, it seems like going with the widest tire you can pinch on the rim does actually give the quickest times.

For a road course (if this falls into your "local events"), this isn't at all recommended...

Try and sell the stockers and pick up some 17x9 rims. You can get some of the Saleen 5-spoke replicas for a little more than $100 each.