Prop Question
 

86 38 Foot Flat Deck Cigarette
1200 Hp Twin 468 Tall Deck BBC's 600h.p. a piece Jomar racing built them.
Trs out drives 1.5 to one.
Bassett Headers.
5k in steering off back.
I had 25 pitch 3 blades it would only turn 4700 rpm and run around 55-60. I went to 23 pitch 3 blades I can get 5100 rpm maybe running 68 mph. I have to gps it.
I thought with 1200 hp I should be able to turn a 23 pitch prop at around 5600.
I have the drives trimmed out at about 3 on the gauge?
I dont want to go to 21 because Ill be in the 4k range crusing and eating gas.
Any Ideas????????

1200HP, and 23 pitch 3 blades at 5100??? Something is not right, my 250HP outboard can turn that same prop to 5400!!!!

Your boat doesn't weigh 15,000# either.

You can't have 2 600hp engines. I have a 1994 Cigarette TOP GUN. It weighs 11,500lbs empty weight. Then I add 200 gallons of fuel, Ice Check and 4 people and I am most likely over 13000lbs. I have 2 supercharged 600hp motors. I have 2 26 pitch lab finished 5 blade Maximus props and I am hitting my rev limiter at 5500rpm. With non labbed 4 blade 26 pitich clever style hydromotive props, I still hit my rev limiter at 5500rpm.

True, but he is talking RPM, those motors should slip the props like mad.

If it helps at all I have what I estimate to be about 575HP - Blown 502's and I spin 26-4 Blades north of 5100 rpms.

Granted this is on my Cafe, but hopefully it helps a little.

I would try a 21 pitch 5 blade labbed Hydomotive!
that will help your cruise speed and slip problem your having!

I was told today weather in michigan makes a difference and that in june, july and august the boat will run 200 less rpm because of water temp and air quailty. My boat weighs 9500 lbs I weight 220 and I have 200 gallons of gas at 8 lbs a gallon. I will keep a eye on the tach as the gas gets low haha

5 Blades on a TRS. NOT Only if your on flat water and the boat never gets any air under it and still 4 blade would be the max.

What speed are you seeing (loaded) with the 26 pitch and that setup on flat water? Are you on TRSs? What's cruise speed? Are those blades labbed, Bravo 1 blades?