Enertia Propeller RPM change per pitch

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mpilot
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Re: Enertia Propeller RPM change per pitch

#16 Post by mpilot » Wed May 10, 2017 8:16 pm

I'm still wondering what gains you are looking to make. If its like my boat they ran a ton of props when testing and the one on it is the best all around. I think virtually all tritoons I've seen are running the 15x15. Some have run the 15.3x14 and the bigger diameter and lower pitch gives a ton of low end punch but is slower at a higher rpm at wot which translates into a good bit more fuel burn. I don't mean this next statement condescending at all, so please don't take it that way. A lot of people aren't aware of what the pitch actually means so they are playing around with something they don't fully understand. The pitch number is the inches the propeller travels in one rotation thus lowering the pitch one inch means one less inch of travel and even going through a gear house it adds up to thousands of inches a minute then multiple miles per hour.

The stuff I've read said running the 150s in the bottom half of the recommended range is beneficial for the engine as its working less.

If you are interested in gaining top end you can also drop diameter which should result in a little more top end and more rpm. In the vhull world it's a little easier to predict. In a toon you can lose top end because it can cause your slip numbers to go up going to the smaller prop and you will lose some power out of the hole.

For example, I ran a 14x20 most days on my vhull and could out perform the original specs for top end but with more than 3 people on the boat or towing a skier it was miserable and would struggle to plane, so I'd jump up to a 15x17 or 18, lose a ton of top end but gain a heck of a hole shot to get on plane or pull people.

DWRAT
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Re: Enertia Propeller RPM change per pitch

#17 Post by DWRAT » Wed May 10, 2017 9:14 pm

mpilot,
I need a high elevation prop for when I go to Lake Powell.
My current setup is great, I can't ask for more.
2012 SouthBay 722CRO 115hp Merc 4-stroke. Edit, make that a 150hp Merc 4-stroke now.

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mpilot
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Re: Enertia Propeller RPM change per pitch

#18 Post by mpilot » Wed May 10, 2017 9:52 pm

[quote="DWRAT"]mpilot,
I need a high elevation prop for when I go to Lake Powell.
My current setup is great, I can't ask for more.[/quote]

That makes more sense now. I'd try it as it is and see what happens. According to the manual the motor compensates some and by the math you will lose about 15% horsepower but it doesn't say anything about rpm dropping. Only says to change pitch to compensate for power loss. I'd drop down to the 14 but wouldn't go much lower than that. You could always carry a cheap aluminium prop and hub kit the next time you go. It won't be apples to apples but you may not need it, and could return it if you don't use it.

Edit to add: No that's a good setup as is and very low slip. I'm lucky to hit 38 with mine on a good day.

DWRAT
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Re: Enertia Propeller RPM change per pitch

#19 Post by DWRAT » Thu May 11, 2017 6:27 am

[quote="mpilot"]
Edit to add: No that's a good setup as is and very low slip. I'm lucky to hit 38 with mine on a good day.[/quote]

38 mph will probably be my top speed in a open lake.
Remember, I was in the Colorado river and had a good tail wind.
2012 SouthBay 722CRO 115hp Merc 4-stroke. Edit, make that a 150hp Merc 4-stroke now.

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zoom650
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Re: Enertia Propeller RPM change per pitch

#20 Post by zoom650 » Thu May 11, 2017 11:21 am

mpilot wrote: "I think he is running the standard 150 like mine and not the Verado, but I may be wrong. The 150 4 stroke's WOT range is 5000-5800 so the OP is well within that range. The Verado's have a much higher max rpm than the standard 4 stroke so OP wouldn't be within range on a Verado but is there with the current setup."

I commented since I had the 14P Enertia prop.
Michael and Laura
'12 Ford F150 Lariat SuperCrew Ecoboost
'14 Harris Solstice 220, P3 tritoon, Mercury Verado 150, Enertia 14p.
prior boat: '02 Century 2600CC, twin Yamaha EFI 200's, full instruments.

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mpilot
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Re: Enertia Propeller RPM change per pitch

#21 Post by mpilot » Thu May 11, 2017 11:53 am

[quote="zoom650"]mpilot wrote: "I think he is running the standard 150 like mine and not the Verado, but I may be wrong. The 150 4 stroke's WOT range is 5000-5800 so the OP is well within that range. The Verado's have a much higher max rpm than the standard 4 stroke so OP wouldn't be within range on a Verado but is there with the current setup."

I commented since I had the 14P Enertia prop.[/quote]

Gotcha, I just wanted to make sure everyone is clear that is a totally different animal. Much higher gear ratio and RPM range. For future comparison some of the differences are below. If he had a Verado 150 he would have no choice but to go down at that RPM as he would be below the specifications on the engine.

150 Four Stroke:
Max RPM Range - 5000-5800
Gear Ratio - 1.92
Cylinders - Straight 4
Cam - SOHC
Displacement - 3.0L
Aspiration - Natural

150 Verado
Max RPM Range - 5800-6400
Gear Ratio - 2.08
Cylinders - Straight 4
Cam - DOHC
Displacement - 1.7 L
Aspiration - Supercharged

DWRAT
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Re: Enertia Propeller RPM change per pitch

#22 Post by DWRAT » Thu May 11, 2017 3:25 pm

The 150 Verado is 1.7L ?
Wow, I wonder how long that motor will last?
2012 SouthBay 722CRO 115hp Merc 4-stroke. Edit, make that a 150hp Merc 4-stroke now.

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mpilot
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Re: Enertia Propeller RPM change per pitch

#23 Post by mpilot » Thu May 11, 2017 6:47 pm

[quote="DWRAT"]The 150 Verado is 1.7L ?
Wow, I wonder how long that motor will last?[/quote]

They actually hold up pretty well unless modified from what I've seen. The 250 & 300 are only a 2.6 L. That supercharger helps them get a lot of power. It is s heavy motor though. The 150 weighs in at 455lbs which is closer to a 2 stroke weight which is why it's a popular choice.

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