prop pitch + RPM

[brodie123]

Hi all;

I have a mercruiser MCM 165 IO 1983 - rebuilt with some upgrades

rated WOT is 3900-4300

I am running at 4500 RPM with a 13.5 19" pitch prop

Should I go to 21? how many RPM change per pitch (rule of thumb) again?

thx

 

[brodie123]

Re: prop pitch + RPM

Is that 1 degree = 200 RPM or 19" to 21" = 200 RPM ???

 

[Don S]

Re: prop pitch + RPM

One inch of pitch (not degrees) will get you 100 to 200 rpm in the real world. Usually closer to 150 or less.

 

[brodie123]

Re: prop pitch + RPM

My rated WOT is 3900-4300

With my 19" (inch not degree thx) I'm getting 4500.

Should I go 21"?

I have good hole shot currently - just looking for best peformance.