Reply to "Build Your Own 91 octane, 500 HP, 377CID CLEVELAND?"

I think Mark is on his way towards building a nice motor. I love the Strip Dommy intake for the way it takes maximum advantage of the 4V cylinder head's high rpm capabilities. The lower rpm performance of the manifold is not the best, but it seems to do alright in the Pantera.

The 351 Cleveland can make 500 bhp with a cam having lobe lift in the 0.600" range, at 6500 to 7000 rpm. Mark's 377 stroker should be able to hit 500 bhp at a bit lower rpm, perhaps as low as 6200 rpm.

Head work needed on the intake side is minimal: Bowl clean-up and a multi-angle valve job. The exhaust needs more work, in the port roof, the short side radius, and some unshrouding in the combustion chamber; but nothing too radical to achieve a goal of 500 bhp.

Recessed valves are a killer on any motor, if the heads have any valves that are sunk into the seats (recessed) you want to repair them. Install seats or grind the chambers and get all the valves sitting on top of the seats, not sunken into them.

Finally there's the exhaust system as Doug so rightly mentions, you want the back pressure low enough to achieve your goal of 500 bhp, and to allow the engine to rev as high as you expect. But it also has to meet your noise expectations. High output verses moderate exhaust volume is definitely a juggling act with the Pantera.