Hi, I have recently purchased a '73 32 foot burnscraft with a volvo penta stern drive and a 350 chevy engine. I get about 1 mile to the gallon. What size prop should I Have? For me to run about 10 mph I am turning about 3000 rpm. I think my prop is 14 1/4 inches in dia. Everyone that I talk to tells me that I need a much bigger prop,is this true? I would like to be able to cruise at about 15 to 20 mph at about 2000 to 2500 rpm, is this possible? Can anyone help? Thanks!

You should prop to achieve 4000 to 4200 Rpm at wide open throttle, with that year engine. The prop you have is probably inadequate.

The ability to plane your boat will depend on how heavy you have it loaded.

You probably will not be able to do what you want, as you can run at hull speed (9- 10 mph), or get it up on plane 3400+ RPM with the right prop.

Keep us informed.
OLD HOUSEBOATER38780.5368634259

[QUOTE=OLD HOUSEBOATER]You should prop to achieve 4000 to
4200 Rpm at wide open throttle, with that year engine. The prop
you have is probably inadequate.

The ability to plane your boat will depend on how heavy you have it loaded.

You probably will not be able to do what you want, as you can run at
hull speed (9- 10 mph), or get it up on plane 3400+ RPM with the right
prop.

Keep us informed.
Hey Old Houseboater, Thanks for the
information. I am going to visit one my local boat dealers and see if I
can get a test prop. I don't want to try to go all that fast , I just
want to try to half way keep up with my buddys pontoon boats. I will
let you know how it goes. Thanks again.