voretch said the shm headers WILL fit as long as they just go out and not up, which is what they do. so the shaft clearence should be a non-issue. as far as 1/4 times, looking at some plots from other s/c contours (not with all the same mods) i would say you should run low to mid 14's i doubt you will ever see 13's because you just don't have any torque where you would need it to dip into the 13 second mark. granted, on a faster track you might see 13's, but that would be the same track a stock svt would dip into the 14's... so i would say on average he shaved a little over a second off his 1/4 time
