I have been searching and what I found tells me that early Mercedes SL300-600 stock 16" x 8" rims with backspacing of 5.16" and a offset of 23mm will work for drag tires on the xfire. I want a set of rims/tires for the back when my son and I go drag racing. I dont mind spending the money, but if its for just a 1/4 mile at a time. Are there any rims from other cars that work and are lighter? Thanks for any input. Here is video of my son(SouthernBronco) taking a modded GTO off the line. The GTO got him by 1/4 car on the top end..it was close.