Prop ideas

I have a 1995 crestliner 1950 sportfish with a 4.3 Volvo penta sx drive, seems to reach proper wot but only runs about 35 mph, I think its a 14×15 on it now, whats others running for top end and prop size?

What’s the rpms getting to?

about 4500 alone in boat . its a 15 1/4 x 15 prop now

From what I can gather 44-4800 is top RPM. You could drop a pitch to squeeze out a bit more.

Is your motor new to you? Are you happy with planing out and handling now?

Has the motor been tuned up lately? Obviously something you don’t want to spend money on if it’s running good but I just squeezed out 5mph out my outboard by going over it well and a de-carbon.

I’m not an expert, just asking some ?’s

Just had it gone through last year, ive had it for awhile, just seems like it should be faster but it is a big beast.

Looking up weights your boat & motor looks to be at 2500#, my ’94 186 Phantom SST with a 120 together is about 1800#, if I get 44mph with a much faster hull(foot skinnier), and your 4.3 puts out about 190hp with the added weight it seems to be about right.

http://www.nadaguides.com/Boats/1995/Crestliner-Inc

Prop expert needed here.

Looked again at #’s and your boat with an outboard would only weigh 40# more than mine(1440). Suprised stern drives add that much.

Good luck man!

get a 17…. BOOM ! Not an expert BTW.

A friend had a 96 1850 sportfish w/4.3 190hp Penta sx. He sold it this spring with original aluminum prop. He had a mercury tempest 2 on it. It is, I think a 14.25×21. He said that performed well. He was turning about the same rpm 4600 and 44 mph. I have the prop and I’m fairly sure he still has the Volvo hub if you want to test it. I live in the north suburbs of twin cities.

That’s a pretty close comparison, Its hard to get the right prop since you buy it you own it, thinking if going the 14 x19

And I might take you up on that, I would sure pay you for your trouble

If it works well you can buy it. He wants $325 for it. If it doesn’t work well you’re closer to figuring out what you need.

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Call the experts

http://www.propmd.com/

These guys are awesome. You give them your RPM and speed, they send you a prop. You try it and give them the RPM and speed again. They do this until you have the perfect prop. You only buy the one you decide on. Great company!!

I’ve purchased a few SS props from them and have been very happy. Price was great too! Around $300-350. Cheaper than the used ones on craigslist.