Another subject I've been reading up on and wouldn't mind some input from the jet side.

Glasscutter i thaught  dual planes make help more torqur

Well I haven't got mine on the water yet so I don't run lol but I see your point so if I made 470 horse what manifold would squeeze more out a 460

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3-4k isn't really "low end" when it takes 3k to stay on plane and 4800-5000 is your red line.  When you drive a jet it is generally going from zero to 35-50 mph before letting off.  No one drives a car like a boat.

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Cars and boats = Apples and oranges

Nothing you read about what works for cars applies to boats.  Well almost nothing.  You are pretty limited to working with a powerband between 3000 and 5000 rpm.  Nothing above 5,500 rpm matters.  The dyno in your ass is never going to notice whether you low end torque has changed a few foot pounds under 3,000 rpm.

Here is a good read if you really want to start understanding intake manifold science.