What props on flat bottom Gun??
#1
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Joined: Aug 2009
Posts: 140
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From: LOTO, MO
I have a 1988 Top Gun with Twin 850 HP blower motors #5 drives on boxes prop shaft 1" below hull. We will be able to change blower pulleys and get about 1000 HP out of them. Do I need two sets of props or can I find a happy medium? boat is in the process of being totally re-done and were ready to find some props! We are currently running 17" diameter 28 pitch 4 blades, have not had the boat in the water but im sure thats not near enough prop? I've also been told to go to a 5 blade to help the boat plane. ( it use to take almost the rev limiter before it would plane) Any input would be greatly appreciated!
Thanks! Mike MWC
Thanks! Mike MWC
#3
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Joined: Dec 2009
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From: Grain Valley,Mo
You might lose some speed with 5 blade but it should get on plane better. Get in touch with Brett from BBlades they have a prop test program I have never talked to him but alot of members use him and he is highly recommened really nows his stuff
#4
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Joined: Oct 2009
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From: Splendora, TX
I have 5 blade maximus props on my flat bottom 1994 Gun. 605hp and my max speed is 73mph. From what others are telling me, I should be doing 80+mph. I would stay with 4 blades. 5 blades gives you too much stern lift. If you want to increase your cruise speed, 5 blades are the way to go. Top End Su?ks.
#6
I may have some test props that you might decide to try. You can rent the propellers without buying them.
Call us if you wish to discuss this.
Thanks,
Brett
Call us if you wish to discuss this.
Thanks,
Brett
__________________
Brett Anderson / BBLADES Professional Propellers
920-295-4435 http://www.bblades.com/
[email protected]
Brett Anderson / BBLADES Professional Propellers
920-295-4435 http://www.bblades.com/
[email protected]
#7
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Joined: Apr 2007
Posts: 595
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From: Ontario
I have the exact same setup as you, i am running 17.5x29 4 blades and prop shaft is level with the bottom. You are right, It is a chore to get on plane and takes some time. I just added 2" spacers and didn't make much of a difference that i can see. i've hit 97mph with this setup but seems to like to run 94 everyday. i've tried spinning in and out, "in" carries the bow quite a bit more than "out". I wouldn't be concerned about getting on plane, just put your drives in and tabs down...it will bite!....try what you have and see how it runs....when will your boat be ready to hit the water?
#9
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From: LOTO, MO
Boat should be kicking roost by the 4th! I have merc boxes so I put them on the lowest setting, they were in the middle. I have the drives turning in now, they were out. What were your results with the 34s on? Im thinking of going to a 32x18?? Ill probably just contact Bblades and do some testing when the time comes.
#10
What ratio are your drives?
I'm running 1.61 wet-sump #6's on my '88 with 800 per side. 16.5 4blade 30P Mercs. My drives are turning out and the boat planes like a Bravo boat. The bullets of the drives are almost 1" above the bottom surface. 6100 WOT in the low to mid 80's.
Craig
I'm running 1.61 wet-sump #6's on my '88 with 800 per side. 16.5 4blade 30P Mercs. My drives are turning out and the boat planes like a Bravo boat. The bullets of the drives are almost 1" above the bottom surface. 6100 WOT in the low to mid 80's.
Craig



