I just wore out my M/T 315/60/R15 drag radials. I am looking to get a new set of drag radials. I am not locked in on any one brand. What do you guys think is the best drag radial, out there right now? My engine is a 2008 Z06 LS7, in a 1932 pro street truck. It is stock except for headers. Do you think I am running to large a tire, or do I need a larger one? I can run up to a 15.50 x 29.5 tire if I need to. The truck has run 6.30s on motor. But lately has fallen off to 6.50s. I think its in the tires because, my 60s have fallen off also. Will a smaller tire hook as good and pick me up some? What do you guys think?