Seth437

Hello,
I just bought a 09 26 OL. So this has a bravo 1 x drive and came with a bravo 28p prop on the boat and also had a spare 28p sitting in the cuddly. had it out yesterday for the first time. It appears this is not propped correctly. Full tank of fuel and 4 adults on board.. Seems sluggish getting on plane. Once on plane and trimmed up it cruises pretty well. But at wot it will over rev. I was seeing 56-57 mph on gps at like 5200-5300 and I would get an alarm. I should be at around 5000 max correct? Why would someone want a prop like this. I would expect it to under rev with a prop this aggressive. Any help would be great. I believe I should be mid 60’s with a little lighter load than I had thanks in advance.

liberator221

Something doesn’t add up. Run your numbers through a slip calculator. Think it will be way high.
Turning a 28 pitch 5200 should be close to 70 with a 1.5 ratio drive.

Seth437

That’s what I was thinking. It doesn’t make sense at all. I did quick math and got about you got for speed. I think the prop has been messed with.

Seth437

It’s not a 1.50 drive it says 1.65 on it

87MirageIntruder

The rev limiter on a 496HO is set at 5150 from the factory FYI

Seth437

It was reving over that. I saw it hit 5300 and alarm came on and I backed out.

madflavors26

Seems way off. I'm spinning a 24P 4 blade to 5200 and getting 72 GPS. This is with 520HP

liberator221

Running your numbers in calculator with 1.65 drive I get 31% slip. Guess that is possible with real bad prop. What is the prop?( brand, diameter, blades)
Not being degrading in any way it are you trimmed out correctly?
WOT and bump drive up very slowly?

Seth437

Prop is a bravo ss 28p. don’t know diameter and don’t know if it has been messed with. No damage on prop. My winterizing guy said it had definitely been messed with. There is a cup at the end. Boat is out being winterized so I can’t give diameter. I will once I have the boat back. As far as trim I am trimmed up nearly all the way. Like trim gauge is reading between 1/2 and 3/4 up.

Griff

Tachs are often off by 100+rpms.
Did this boat come from somewhere with high elevation??? That is usually the only time 1.65's get used.