I thought I had seen your bottom end specs, but when I went back to look I didn't see it.
Yep, your bottom end is fine.

Your combo with marine exhausts ought to fall short of 450hp.
I'm not real familiar with the weak links in a Volvo DP, but I would be leery of running it over 5,500 without upgrading the bearings to a higher precision spec AND a looser operating clearance (ABEC 5 and C3 probably).

Your cam USUALLY peaks in the 5300 range on a 800cfm 502 single plane with Gil exhausts. A 468 probably another 100 revs with the same carb.

I'm looking forward to following your progress.

cheers
MC

So you r using a garden hose to feed the sea pump ,,bet u r getting. Lil to much water ,,,but like what has been said it dont sound rite

The seawater pump is positive displacement within normal pressure ranges. If you run thru the pump, it will do a fairly good job of regulating the water flow. Obviously, you don't want to blast 110 psi into the impeller pump (some marinas around here have 120+ psi), but outside of that, the hose flow shouldn't be too harsh if run thru the impeller pump.

A bit of update. last bit welded up today. pressure test tonight, polish this weekend.

currently looking for pre-molded hose in the gates catalog