my truck is a 99 dodge 4x4 hts auto, edge juice w/attitude, AFE cold air intake, 4in straight pipe w/6in tip, ats manifold, holly blue fuel pump w/big lines 4. 10 gears and ive been runnin 3rd down the track/315/75R16 tires. ive been runnin with the suspension blocked up but allowing 1 inch of travel and deflating my tires to about 35 psi my last pull but havent really done anything different.