Best prop for my boat?

Evanrm105

Cadet
Joined
Jul 8, 2020
Messages
6
So I just recently bought a 19’ Sea Pro with a 1989 90 horsepower Evinrude V4 two stroke on it. It only
tops out at 27 and with more than 2 people, it will hardly reach 24. I’ve gotten similar speeds on a pontoon, with more people and the same horsepower, so I think it’s my prop. I cleaned my carbs, as one of the jets seemed clogged, but I’m not sure that will help, I’ll test tomorrow.

So long story short, it struggles to go fast, especially with people and it currently has a 13X19 prop on it. My boss recommended a 13X17, what do you guys think?
 

WesNewell

Chief Petty Officer
Joined
Jan 3, 2018
Messages
497
I think if you gave us the weight of your boat, the weight of people and gear, the gear ratio of you engine, and your tach reading at wot, I could give you a pretty good answer.
 

Evanrm105

Cadet
Joined
Jul 8, 2020
Messages
6
My boat weighs about 1750 with no engine or gear, about 700 pounds of people and gear, and my engine weighs about 320 pounds.
gear ratio is 2.00 I believe
 

WesNewell

Chief Petty Officer
Joined
Jan 3, 2018
Messages
497
Although not your engine, this should be pretty close to what you want if it's a 2.0 gr.
[h=3]Your setup[/h]
  • Boat type: Runabout - Cuddy
  • Usage: Overall good performance/0 ft
  • Engine Manufacturer:
    Evinrude
  • Engine Type: Outboard
  • Engine Year: 2001
  • Number of Engines: One
  • Engine Family: V4 DFI 2-Stroke
  • Engine: 90 Ficht
  • Drive / Gear Case: Evinrude 75-130 hp 2-Stroke 2.0 Ratio
[h=3]Details[/h]
  • Calculated Pitch: 16.33
  • Calculated Weight with engine(s): 2,890.40 lbs
  • Calculated Engine RPM: 5,500
  • Calculated Boat Speed: 38.24 mph
 

Alissas

Recruit
Joined
Aug 10, 2020
Messages
2
If the RPM is higher, switch to a propeller with higher pitched blades. Each inch of pitch size will change the RPM by 150-200 RPM. Aim for the midpoint or higher of the recommended operating range.
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,721
Considering my past boats, at least one similar and higher powered and all, just off the cuff, 17P sounds like a good number. If your engine was the next size up the 19 would be Ok. (opinion). 38 MPH may be a few MPH high for the estimate but it should at least get you the mid 30's with that load.....my similar boat with a 125 (115 today's prop rating), 19P kissed 39 with just me.
 

Alissas

Recruit
Joined
Aug 10, 2020
Messages
2
A lower pitched propeller will create more power due to more engine RPMs, but the boat will move slower. A higher pitched prop allows the boat to move faster by travelling a farther distance with each rotation visit myprepaidcenter
 
Top