Talked to a guy at Indy Cylinder Heads at Carlisle. He recommended the "Indybrocks". Bare Edelbrock castings that they do their own thing on. They flow 280 cfm on the intake side out of the box, have aluminum roller rockers, I think he said 2.05 valves, 650 lift springs, offset push rod location like T/A's, push rods and head bolts also included. Told me with a 408 and my cam(solid roller 242/248@,050 and .570/.576 lift and a 10:1 compression I would be looking at 550-600 HP. What do you think??