Most of the ones I've seen run 15s and 14s, with a few just a little faster. Bolt-on Mustang GTs were owning the crap out of the N/A and FI Honda (just one Civic w/ turbo) crew last time at the track. There are some fast ones out there, but I think typically even with mods they aren't that fast. Just fast enough to give a stock or lightly modded WRX a nice run.
Still my favorites are the H22 swaps...those move.