Multiple props

[Fiberform]

I am just curious about have different props for different purposes. Currently I have a 1982 Sea Sprite with a 120 OMC I/O and I think a 19 pitch prop. It runs in the recommended rpm range at about 4500rpm with 32mph showing on the speedo. I am considering buying a Raker 24 pitch stainless steel prop for top end speed and cruising power. I would also like to have a prop for low end for pulling tubers and skiiers with consistent power at lower speeds. My question is will the Raker prop give me more speed, can I get a low end power prop, and is this all worth it or should I just try to stay with the middle of the road prop? Thanks for any information.

 

[Speedwagon]

Re: Multiple props

Well, I just recently got a boat myself. And it came with a 19p prop on it. With a 19p, I could over rev the crap out of the engine while I was the only one in the boat, and I couldn't get it up to top speed. So I went up to a 23p prop, and now I can get the speed up nicely, and it won't overrev(unless I play with the pitch). So I'm keeping both the 19 and 23. One for the speed, and the other for the power(like a loaded down boat, pulling a tuber or something).<br /><br />I am certainly happy with my 23p, but I haven't really done anything to warrant the use of the 19p yet. But like I said, just got the boat, and it's my first one. And it was recommended by people here to keep the 19 as a spare, and for power when needed.

 

[tommays]

Re: Multiple props

you allready have the correct prop with the 19 in for normal use <br /><br />a 24 in would cause engine dammage because the motor will not be able to reach the recomended rpm range<br /><br />it usally takes a nice size V-8 motor to use a 24 in prop and you would be doing aroung 65 mph <br /><br />if your haveing trouble with water sports than the 17in would help get the boat on plane quicker but you have to carefull not to go over ther 4500 WOT<br /><br />tommays

 

[TilliamWe]

Re: Multiple props

Propping is a study in compromise. It's like having a direct drive in your car, one gear only. You usually won;t get awesome out of the hole acceleration and blistering top end. And especially not with 120hp.<br />If your 19 turns the recommended WOT rpm, I'll bet you a dollar that it can't turn that 24 pitch past about 3700 rpm, or wherever your peak torque is. Sounds to me like the prop pitch you have now is about right. Your only things left to play with are, stainless in the same size and maybe 4 or 5 blade props. The 24 will not be a good prop for that boat, if the info you supplied is accurate.