Well, there is 50 more HP to be had above 5k.... I will agree the 2.3 is holding it back but it is gaining power at a decent rate still. 5600 is where I want to run it. Seems like a good spot for this engine. Here is picture at reference. Rear entry top mount.
[ATTACH=CONFIG]562589[/ATTACH]

Dustin says 18k max rotor speed. Changing to the 3.125 upper with 8.75 lower the speed will be 15,680 at 5600. Overall I'm
Just curious on the increased intake duration and it's affect.

That motor needs at least 8* more duration on the intake. Don't focus on peak hp. Your boat doesn't care about horsepower. Torque is what moves the boat. Look at the dyno sheet and see where the torque starts nosing over. If you want the motor to perform past 5,000 rpm you need to move the torque up in the motor. To have a noticeable difference in the power curve you need atleast a difference of 8 numbers in duration. I think it could also benefit from a tighter LSA. With the tighter LSA you will Loose peak numbers however your horsepower and torque numbers will not run away from each other as fast. And that's what you want in a boat. When they run away from each other to quickly the motor is done.

You mean 8 degrees less duration on the intake? So turning it into a 525 cam?

8 more

8 more on intake? Reverse split like a turbo grind... 253/245... this is a new thought

If torque is all that mattered we would all be limiting our boats at 4600 rpm. And my duramax would pull those LOTO hills much better at its peak torque of 1600... which is not the case. Sorry, not buying what you are selling Baja.

I never said a reverse split. I said if you want to move the torque up in the motor you need a minimum of 8* more on the intake to see a noticeable difference. I never even mentioned the exhaust.

So you're saying you need 250's+ duration cam for good power up to 6k in a 502ci engine... I see :/

Bingo