Prop Question

[Starman]

I have a 80 HP Mercury running a 13X21P prop. *Boat runs 36 MPH, 4,500 RPM at WOT.

My questions are:

1. Could I get more speed going with a 19P running higher RPM.

2. Would my gas mileage be less running higher RPM.

 

[Spivy30]

Re: Prop Question

I have a 80 HP Mercury running a 13X21P prop. *Boat runs 36 MPH, 4,500 RPM at WOT.

My questions are:

1. Could I get more speed going with a 19P running higher RPM.

2. Would my gas mileage be less running higher RPM.

Starman,

You're not gonna get any more speed you will actually go a little slower but you will have faster holeshot and more power to pull water skiiers and tubers, and yes you will burn more fuel. If you want more speed you're going to need a higher pitch prop like a 23p but that will only help you if your motor has enough power to get you between 4500-5500 rpms

my guess is no if you're only getting 4500rpms with a 21p you will get less with a 23p

For more speed try changing your plugs and running some decarb through the motor, try a product like quicksilver power tune it will clean your motor of any carbon build up which is the killer of outboards.