Every car we've ever taken slicks off of and put drag radials on has gone faster! Be it s 67 mustang w/ 521 big block that picked up .1 or a 91 Hatchback w/ a stock bottom end motor and novi2000 picking up .2, they have all gone faster. It has everything to do w/ the side wall of the tire being more stiff and the stability at the top end. Your mph will also pick up on a radial. I've seed stock
suspension cars, and when I say stock I mean factory original
suspension parts on cars w/ radials in the 1.5 sixty foot range. Not to mention, who wants to change there tires at the track, or try to drive on the highway w/ slicks? All of our cars are driven to the track!