Intek = Innovative Technology! The 6.5 I/C would be a better engine. The I/C (Industrial/Commercial) engines are more durable than the standard Intek engines. They have cast iron cylinder bores, ball bearing PTO crankshafts, better valves, etc. The 9.00 gross torque is the same horsepower rating, they just list the torque figures now instead of HP on their stickers.