DragStuff

Which is smaller the 275 or 28 x 10.5 My nova has a 15 x 8 with a 5.5 backspacing and a spacer and the 28 x 10.5 are close to my fender wheel i had to roll the lip and i have about a half a inch clearence will i have more clearence with the drag radials? Also do drag radials grow like slicks ? thanks

The 10.5 is a little wider than the DR and no the DR does not grow but the 10.5 will. The 10.5 tire will be more foregiving than the DR and in my expereince is easer to tune to.
Before I built the car I have now (a DR tired car) I only ran 29.5x10.5's and had better results in tuning the car to them. The DR's are though tires to learn.

It kinda varies from tire maker to tire maker, but most 275/60/15 drag radials are a true 28" diameter, but the width can vary. I know the hoosiers are wider than the mickey t's, in both the section width(@1/2") and the tread width(@1"). I would think the 28x10.5 slick would be a little wider than both. As for tire growth, the slick will grow at least 1"+ in diameter, the radial has hardly any growth at all. If you want to go radial, I recommend the hoosier over the mickey, it recovers WAY better and is WAY more consistant and not as picky about track temp and prep. It acts more like a true slick instead of a typical drag radial. Some guys here have had good luck with the goodyear radials also, but the real fast guys are all on hoosiers.