21p to 23p high 5?

[Chuckles88]

I tried a 4 blade 14.5”x 20p and a high 5 21p. The 4 blade was running about 5200rpms on a 5.0 gxi and the high 5 was at 5000-5100. The high 5 did wonders and felt smooth. I am a little high for the wot rpms at 5000 being the max. Should I try to find a high 5 23p or call it goood? Thanks

 

[Sea Rider]

What's the max wot rpm range factory stated for that motor ? How loaded was the combo when achieved 5000-5100 wot rpm with the high 5 prop ?

Happy Boating

 

[jimmbo]

Going to the 23 would probably drop your rpm down to 4700 which would place you in the lower end of your engine's WOT range(4600 - 5000). If you were lightly loaded when you ran this test, but are usually more heavily loaded when boating, the 21 might be perfect, especially if you want to do any water sports.
Getting rid of any unneeded weight/ballast(Wife, Kids, Mother-in-Law) from the boat might help if you go with the 23. Is the hull clean? Load properly distributed? Are you using the trim to best advantage?
Does Merc offer the High 5 in one inch Increments?

 

[Chuckles88]

I ran it with just me in the boat with a full tank. I do have two batteries on starboard side as well. That was the best run with trim. I tested it again with the wife and two smaller kids and the necessities for a day on the water and it was close to 5000 rpm. We are mostly using it for the water sports.

 

[Scott Danforth]

I would leave it, simply carry more beer when you are boating without the kids, or back the throttle off a bit.

 

[jimmbo]

I ran it with just me in the boat with a full tank. I do have two batteries on starboard side as well. That was the best run with trim. I tested it again with the wife and two smaller kids and the necessities for a day on the water and it was close to 5000 rpm. We are mostly using it for the water sports.

Yeah I agree with Scott, just leave as it is. It is not a serious over rev, and any load will bring it down

 

[Chuckles88]

Thanks! Sounds like a better problem to have than most others.

 

[QBhoy]

I tried a 4 blade 14.5”x 20p and a high 5 21p. The 4 blade was running about 5200rpms on a 5.0 gxi and the high 5 was at 5000-5100. The high 5 did wonders and felt smooth. I am a little high for the wot rpms at 5000 being the max. Should I try to find a high 5 23p or call it goood? Thanks

Hi
depending on what you want from the boat really.
If you are water sports daft...then stick with the high 5 and you could even go to the higher pitch easy.
If you want general good performance or even blistering performance and good cruising. Go for a 3 blade like an enertia or tempest. The high 5 is only good at one thing. The issue you might have if this is the case, is that you have no good reference point if only from a 4 blade and a 5 blade. These will always react different to a 3 blade and usually see better acceleration but worse top end.
If I was being fussy...your engine should limit at exactly 5150 rpm. Small detail though.

 

[Chuckles88]

I started with a 3 blade 19p stainless and couldn’t find wot. It would hit 5100 with a quarter throttle left. I had a friend let me use the high 5 21p and purchased a 4 blade 20p. The high 5 had the best holeshot and acceleration and had a top speed of 6 mph more than the 3 blade.

 

[QBhoy]

I started with a 3 blade 19p stainless and couldn’t find wot. It would hit 5100 with a quarter throttle left. I had a friend let me use the high 5 21p and purchased a 4 blade 20p. The high 5 had the best holeshot and acceleration and had a top speed of 6 mph more than the 3 blade.

Ok. But if it’s top speed to be compared. I’m 99% certain a good 3 blade of the same pitch as a hi 5 would completely destroy the 5 blade any given time.

 

[Chuckles88]

I agree,but at the 19p 3 blade I was under propped. It was terrible from 0-25 mph. The high 5 got me up in seconds. I was just wondering if i could get away with going to a high 5 23p as my rpms on the 21 were a little high.

 

[QBhoy]

Yeah. The 19” 3 blade would be. But if you tried a fairly decent 21” 3 blade you might be surprised at the result.