Mass air flow sensors fail most often in cars but a $20 air filter replacement every 12,000 miles prevents the $250-400 repair bills most drivers face.

Since the inception of GMHTP's LS1 project car, we've cut a full second off its ET (13.36 to 12.36), added 6 mph (103 to 109) to the trap speed, and added 55 horses and 48-foot pounds to the wheels.