26ft trojan What size props should be on my single engine 351 Windsor on a 26 foot Trojan day cruiser I only get 1214 miles an hour I think I should

Plantmoore

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Sep 18, 2022
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Have a 26 foot 1970 for Trojan J cruiser I’m only getting 14 miles an hour what size prop should I have on there for Lake of the Ozarks in Missouri I bought it from Lake Michigan I’m thinking they have some different size prop on because of water conditions
 

jlh3rd

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Jul 10, 2017
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you don't prop a boat for mph specifically. You prop it to operate the engine in its specified rpm range, ideally at max throttle showing max rpm. That means you start with knowing the engine is developing its normal power.
So, what is the rpm range of the engine and what is the rpm at max throttle...
 

jimmbo

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May 24, 2004
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Likely 3800-4200 is the WOT range for an Engine of that era
 

airshot

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Jul 22, 2008
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Yea, My vote would be a thorough tuneup and comp check, before worrying about a prop.
 

Plantmoore

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Next time out I will get those figures the boat runs fine and the motor is in perfect running condition I really don’t like putting my boat in full RPMs but I will and let you know the speed thank you
 

Plantmoore

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Sep 18, 2022
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I know when I look up what the boat supposed to do it should do 25 miles an hour it’s not getting anywhere near that and I think the prop is spending as much as it can round these old boats my whole life my old Chris Craft used to run 30 and it was 28 foot with a 283 do you think that they use different props because of water conditions at all it was a fishing charter boat pump in Chicago before I bought it
 

airshot

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Jul 22, 2008
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Next time out I will get those figures the boat runs fine and the motor is in perfect running condition I really don’t like putting my boat in full RPMs but I will and let you know the speed thank you
Getting her up to wot for a short period of time is good for it....however it is the wot RPM that will be the most important....do you moor the boat ?? I have saw growth cut a boats speed in half, a clean bottom can make a world of difference..
 

jlh3rd

Chief Petty Officer
Joined
Jul 10, 2017
Messages
413
I know when I look up what the boat supposed to do it should do 25 miles an hour it’s not getting anywhere near that and I think the prop is spending as much as it can round these old boats my whole life my old Chris Craft used to run 30 and it was 28 foot with a 283 do you think that they use different props because of water conditions at all it was a fishing charter boat pump in Chicago before I bought it

got it....but your asking a question on the internet so we have to answer based on our knowledge and what your numbers tell us....
 
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