Prop diameter ??

[Jrjbass]

I've got a Yamaha 2016 sho 225 horse. I'm running a 24 pitch T1 with a 15 1/8 diam. Would a 14 1/2 work out as well? Oh I'm in a 2011 z520 w a hydro jack

[BlazerVA]

You’ll gain rpm by dropping diameter. It’s about 150 rpm per 1/4”. Just like changing pitch.

[lpugh]

Depend on the boat and load

[21XDC]

You’ll gain rpm by dropping diameter. It’s about 150 rpm per 1/4”. Just like changing pitch.

I have never found this to be true.... Too many variables to say that. Larger diameter props can generally run higher on the jackplate and gain rpms and speed... But not always. There is no "Rule of thumb" on this subject.