Water pressure and rpm's - 1995 2 stroker

[gomester]

What water pressure and rpm's should I be running? 1995 Yamaha Pro-v 150 hp 2-stroke with 25p 3 blade SS prop. Running 17-20psi at around 5200 - 5400 rpm. Water pressure drops to about 17 at about 5400 rpm but 5200 and below at 20 psi or better.
What rpm's and water pressure should be keeping it at for maximum performance. Or am I already there?

 

[ondarvr]

It depends on several things, so most of the time you check the pressure with a new impeller and then when it drops off or changes you know there's an issue.

 

[bruceb58]

The spec for water pressure will be in the service manual. For the Merc outboard in my sig(Yamaha power head), the spec is 2-7 PSI @ 750 RPM...6-20 PSI @ 5500.