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What size prop do i need

ktmjunkie

Contributing Member
"Hi guys, being new to boats a

"Hi guys, being new to boats and outboards i am not sure what prop i need. I have a 14 ft Fletcher Arrowflight with a 50hp 4cyl 2 stroke Mercury it has a 45p prop on. I have been told that pitch one way gives you better acceleration and pitch the other gives you better top end speed. the prop on there is ally, so is this the right one for my set up or can i improve top end a bit by changing to a different pitch. also what are those wing things that you bolt to the leg and what do they do.?? thanks guys.
regards gordon"
 
"Lets start with the wing thin

"Lets start with the wing things/hydrofoils, they will help put the nose of the boat on the water, they add drag and put more force on the transom and engine mounts. Junk.

Your prop might be a 15p, a 45p would be for the QueenMary2. You can change props for better performance either faster hole shot or higher speed. But you must know the max rpm of the engine, to much load and that 50hp becomes a boat anchor. Same for too many rpms. You can also increase the size of the prop, many combos. I suggest you work out the problems you already have and save your money for beer."
 
"JB thanks for your fast reply

"JB thanks for your fast reply mate all you say has been taken onboard, so hydrofoils are a definate no no then ?? as for the prop, just been outside to check, again you are right mate its a 14p I dont want to load the engine anymore i just thought that by changing the pitch would give me a bit more top end speed.
regards gordon P.S. off to buy some beer.
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"
 
"your boat is heavy enough so

"your boat is heavy enough so the front end settles down on its own. The foils might work on a light jon boat with a large aft load. But extra drag in the water means less speed. For the best performanse put a tach on the boat and then we can get the right prop. You can also change the pin location on the motor to raise/lower the nose. This can also increase the top speed, depending on the load of the boat"
 
"Gordon, going to a higher pit

"Gordon, going to a higher pitch will give you more top end speed. The same as being in 4th gear will let you go faster than being in 3rd gear. However if you want longer engine life stay with a smaller pitch. Imagine how hard your car engine would work starting off in 4th gear all the time. 2 strokes don't like being lugged down..the wrist pins, rods and crankshaft are not that beefy. My prefernce is to have a prop that will tach out slightly above the manufacturers red line...I JUST NEVER TAKE IT OVER THE RED LINE!(important) Set up this way the strain on vital engine compenets is lessened. You loose a couple miles an hour but pass everyone in the lineup at the bank getting loans to replace their worn out outboards."
 
"thanks guys for the replies,

"thanks guys for the replies, question is, where can i buy a tacho for this engine then and would you say that the prop i have is the right one for this set up then.
regards gordon"
 
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