275//50 is what I'm running right now, and I can't get a lick of traction. Plus, the 60's will fill the wheel well up better. I'm hoping to improve on that. Numerous sources have told me the the 60's will get better grip, we'll see. I know that NOTHING is going to be great with this much power.
I believe the Nittos dont hook up as well as the MT's. You may get better traction from the MT's. I am happy with the MTs on mine, but I have @100 horses less