Quote: Retarding the cam will improve top end HP but you will lose bottom end torque due to the reduced cranking pressure.
But since he has more cylinder pressure than he can *use* at low RPM, its not really going to be a problem IMO. When people lose enough low-end to be annoyed, its generally because they're trying to take a stock engine and stuff a much bigger cam in it to get a power gain. Stock compression ratios are usually lower than "advertised" anyway, so you wind up with an engine that has an effective 5:1 ratio at low speed, and life is bad. That's not going to happen here with a true static CR of over 10:1.
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Lou, I think I read your post wrong? Did you suggest that the intake lobes should be bigger? I have always heard the other way around. Is this the latest cam theory, that the intakes should be bigger? One of the reasons I didn't buy a Comp cam for my 360 is that most of their cams were symetrical profiles for some reason.
I think its more of a slant-6 specific thing. I live (mostly) in the Mopar B/RB engine world, and there you have exhaust and intake ports that flow somewhat comparably. In stock and mild build applications, the limiting factor tends to be exhaust manifolding, so for example the Magnum/TNT/Super Commando engines of the 60s got dual-pattern cams with more lift AND duration on the exhaust side. But when you go to headers and big exhaust, the Mopar Performance cams like the "484" and the "509" (which also date back pretty far, at least to the 'Direct Connection' era) become single-pattern. And modern cams like Comp and Hughes for those engines are still either single-pattern or have more duration on the exhaust side, depending on the applicaiton. But the slant is a different beast, and as I understand it the intake side actually starts limiting things first, and its at the head port level not the manifold level.
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I believe Sandy is on the right track. 