prop size for 88 force 85hp?

[north40]

My son just purchased a 1988 85hp force without a prop. Could anyone give info on what diameter and pitch would be needed. He is putting on a 15 ft. fiberglass procraft bass boat which will weigh about 1100 lbs.

 

[rbruce63]

Re: prop size for 88 force 85hp?

For a 1982 85 HP Chrysler with 2:1 gear ratio the standard propeller was 13" diameter X 19" pitch. With this propeller the boat should get into plane and with standard load it should reach 5,500 RPM'S.<br /><br />Be sure to check with the dealer who sold the motor for other propeller choices. Most of the dealers or marine products distributors should take a propeller back if these numbers are not reached and advise you on proper propping.

 

[-Kaos-]

Re: prop size for 88 force 85hp?

I have this same year and the prop size is 13 1/2" with 15 pitch and 15 splines

 

[Frank Acampora]

Re: prop size for 88 force 85hp?

I agree with Bruce 63. A 13 X 19 pitch is probably the one to start with. However, It has been my experience that these engines do not usually perform as well with a cupped prop. The cupping adds the equivalent of about 2 pitches. So, for example: if you elect to buy a cupped Michigan stainless prop, start with a 17 pitch. I run a regular 19 pitch on my 15 foot Glastron deep vee with a 90 chrysler. I use a 17 pitch when water skiing or wakeboarding. Pops out the skier faster.