overdrivegear
Member
Hello everyone,
I have an 84 Bayliner Capri with the little aq125a that runs like a champ. Right now, I'm running a Piranha 14x19 cupped prop getting 4100 RPM at WOT and about 32 MPH. It works great, awesome fuel economy, smooth etc, but the RPM is a little low according to the manufacturer. I know I should be more in the 4400 range for WOT. I also have an aluminum (non-cupped) 15x17 that I put on to pull tubes and skiiers. That prop gets me up to 4500 PRM no prob.
What effect will there be going from a 14x19 cupped Piranha to a 15x19 cupped Piranha? I understand how pitch and slip works, but I don't quite understand how pitch and speed is related to diameter. Would going to a larger diameter with the same pitch bring my RPM down even more?
I'm just trying to squeeze another couple MPH out of my boat.
I have an 84 Bayliner Capri with the little aq125a that runs like a champ. Right now, I'm running a Piranha 14x19 cupped prop getting 4100 RPM at WOT and about 32 MPH. It works great, awesome fuel economy, smooth etc, but the RPM is a little low according to the manufacturer. I know I should be more in the 4400 range for WOT. I also have an aluminum (non-cupped) 15x17 that I put on to pull tubes and skiiers. That prop gets me up to 4500 PRM no prob.
What effect will there be going from a 14x19 cupped Piranha to a 15x19 cupped Piranha? I understand how pitch and slip works, but I don't quite understand how pitch and speed is related to diameter. Would going to a larger diameter with the same pitch bring my RPM down even more?
I'm just trying to squeeze another couple MPH out of my boat.