[Steve C.]

Here is some insight regarding a reasonably good example of a camshaft selection for the projected 650 horsepower goal.

This build was 463 cid using a 4.210" stroke and 6.625" rods.

It used a Custom solid roller cam with 265/270 @.050" / 0.691" lift / 110 LSA. The cylinder heads were similar in that they both were rated 340 cfm at 0.700" lift.
With a 2.190" intake valve. Spring pressure was 230 lbs on the seat. The compression was 11.4:1 in conjunction with 'heart shaped' combustion chambers.

Quite a bit of difference than the 254/262 duration @ .050 mentioned here. And note the valve lift was up near where the heads were rated at.

It too had a carb / intake combination that was cobbled together, but this with a 1050 Dominator carb using an adapter to mount it on a 4150 Victor intake.
Headers were a small 1.750".

The result was 650.4 hp at 6300 rpm (0.437 bsfc) and 596.5 ft.lbs. torque at 4900 rpm.

As typical this post does not represent any endorsement of the combination here, and offered for general interest only.
The engine was dyno tested, but noting the obvious in that the results with different types of engine dynos, test cells and operators can vary all over the map.
Also noting the stroke and rod length difference will alter things a bit.



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