Show you the diff between the 6.1 and 6.4 bone stock my 6.1 on a AW DYNOJET put out 342 hp & 352 tq on 91 gas and 368 hp & 382 tq with cai and custom cmr dyno tune on 91 gas. Bone stock in 1/8 mile with 91 gas it ran 8.39 and with cai,tune and 98 gas it ran 7.95. Race wt on 07 6.1 was 5190 and race wt on MY 12 6.4 was 5492 lbs. LOOKS LIKE YOU GOT A GOOD MOTOR.They put the suspension in track mode and turned off the traction control on the dash. They said if it was left in auto mode they would expect to see slightly lower numbers.