What's the best size prop

Poormansboating

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Got a 1989 85 hp on a 1991 17' Bayliner Capri. Right now I've got a 15" pitch 3 blade and I can get 25 mph maybe 30. It gets there real fast. What prop can I use to get some more top end.
 

Poormansboating

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Will do. Will a small aftermarket work like from AutoZone or any parts store. Or do I need a special one for boat
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Not sure AutoZone has any marine things.

Bring a buddy, have the cowl off and use a photo tach, or get a tinytach. You need to know the RPM the motor is getting to at WOT
 

jerryjerry05

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That boat comes with a 90hp. and a 17 or 19 aluminum.
Your 15p is it aluminum or stainless?
 

Poormansboating

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Factory with a 50hp force. I put the 85 on it. It does really well and gets on plane great now after adding the hydrofoil. Just trying to get a little more top end so I can keep up with friends on the water. The whole shot is amazing as only a few seconds and I'm at top speed.
 

jerryjerry05

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Try your local boat places, some have used props they loan out to make sure you get the right one.
Michigan Propeller has a prop finder service.
Contact them with the info and maybe they can recommend the right one?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Props are so expensive I just want to make sure I make the right call before buying one.
read this on props and the information needed.


you are missing 3 out of 6 bits of very important pieces of information for anyone to make a wild-a$$ guess as to which prop you need.

the most important bit of information is what RPM you are at.
 

Poormansboating

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1989 85hp force outboard, 1992 Bayliner Capri 17' bow rider three blade alluminum prop. 15" x 13 1/2 I believe has a stingray senior hydrofoil. Current speed is 25 to 30 mph. Weight and rpm is n/a yet coming soon. What I'm looking for is more top end speed so I can keep up with buddies a little better.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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what RPM? the RPM of your current setup is the single most important bit of information. keep asking your question, we can not answer it until you post what your RPM is.
 

jerryjerry05

Supreme Mariner
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Messages
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1989 85hp force outboard, 1992 Bayliner Capri 17' bow rider three blade alluminum prop. 15" x 13 1/2 I believe has a stingray senior hydrofoil. Current speed is 25 to 30 mph. Weight and rpm is n/a yet coming soon. What I'm looking for is more top end speed so I can keep up with buddies a little better.
Put a 17-19 on it and you'll go faster
 
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