Russ, now think about that for a minute.

You’re targeting 630-640ft/lbs at 4800rpm.

How would you build this BB Mopar motor to achieve that power level at that rpm, and have that be the point of peak hp?

How high would the low end tq have to be, and how sharply would the curve have to be dropping for 4800rpm to be the point of peak hp?

Your targeting 640ft lbs/585hp@4800....... and that’s going to be the highest hp reading.

The cam I would use to reach the target 640ft/lbs@4800, I’d expect to make peak hp north of 6000 with the heads, induction, exhaust the OP’s build has.

But...... it’s irrelevant....... since it will only rev as high as the load of the pump allows.

The other way to look at it is........ if the pump load limits the rpm to 4800......then, with the motor in use in the boat...... that will be the max HP.