Increase top speed?

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Colemanandrew

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I got a 97 yamaha 30 2 stroke on a 14 ft aluminum war eagle I can top off at about 35-36 but I know I can increase that a little bit. I know the motor can only handle so much any prop pitch increases and maybe how to lift the bow up some? I was thinking higher pitch prop and a whale tail or hydrofoil.
 

airshot

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The whale tails rarely increase speed, give some lift and faster on plane yes, on lighter boats, but increase in speed is something I have never saw in my 60 yrs of boating. As mentioned, wot motor rpm is needed for calculations to be made. Keep in mind, that a higher top speed usually means a longer time to getup on plane, especially when any weight is added. Once you reach max wot rpm on that motor....that is it, only a bigger motor will increase your speed.
 

flatheadsteve

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35mph is impressive from a 30hp on a boat like that. Others have already mentioned it but a rpm reading at wot would let you know if a prop change could do anything for you. Shedding weight wherever possible could gain a few mph but could affect handling if it messes up your weight distribution.
 

jethro

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Yeah, when I take off my hydrofoil from my 25hp the top speed of the boat goes up by about 4 mph. Of course it takes much longer to plane. More drag with the foil that's for sure.
 

Crazyboat

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A jack plate getting the engine up out of the water is the way to go, drop some weight if possible too. Knowing your RPM and adding a racing prop will add a bit too, but then you'll lose in other areas as a racing prop is built for that one purpose.
 

thill

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I would be really happy with 36 mph with a 30 HP engine, but you might also want to try waxing the bottom of the boat. You will probably pick up another couple MPH.
 

Weldorthemagnificent

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Either shave your head and don't wear a shirt or go downstream .😂 Sounds like you're hauling the mail already! Raising the motor on the transom sometimes yields a mph or 2. I used flatbar shims to dial the height in before drilling and bolting the clamp. I started with an inch but had to bring it down to a half to eliminate cavitation in the turns. I left the 2 shims in to share the load with the bolts. Rpm, like everyone says, will tell you where you're at. PXL_20231124_235730478.jpg
 
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