RPM Loss

[propless]

I am going to attempt to ask a question and not wind up in such a battle as my question on a valve to regulate water (the gate valve issue) - although very informative, what a debate!!
I have a 27' Sleekcraft, 454 Indmar with a 12JC pump, 800 holley double pumper & logs. HEI electronics, and a hydrualic place diverter unit. Out of water the motor revs well past 6000 rpm. In the water, I get a maximum of 4100 rpm. Not sure what impeller I am running, however it is aluminum for whatever that is worth and I feel this is my limiter. Boat does get up real quick and plains sweet with the diverter.
Strong motor no problems or issues, but wish to get more more speed (doing about 50mph now), to get more speed I need more rpm's at the nozzle end (I presume).
Oh great jet God's, what shall I do??
As always - your responses are appreciated!

[DOHARA]

PROPLESS, the reason the motor will rev to 6000 rpm out of the water and not in the water is cause the motor doesn't have any load on it. When the pump is in the water it puts a load on engine and won't rev as high or as quick. If you want more mph and rpm's you need more horse power from some engine upgrades and also some pump work like cutting impeller down from an "A" to maybe a "A/B" or a straight "B". I would start with some good perfomance exhaust, a cam and intake manifold, some mild head work and see what performance gains you see. Do a little at a time till you get what your looking for.
GOOD LUCK
DANO

[77charger]

With a boat of that size i would stick to an a an a-b or b would not get out of the hole.Try a cam intake exhaust mods first.Not really a good thing to rev up out of water.When you are in the water thepump has a load working against it kinda like a car when in neutral it revs easily now put in top gear and try again.get it.

[AGGRESSOR JETS]

Your hull is big, you need your A if you cut to a "B" I think you will be sorry. If you want more RPM's Motor time. Dave

[propless]

Appreciate the comments! Thanks