300 HP YAMAHA OUTBOARD

[SharkFighter]

Does anyone know the optimum RPMs for a Yamaha 300 HP HD. The 2004 engine has about 140 hrs on it. I have been running between 4200 and 4700 RPMs. At 4700 RPMs I am running at about 30 knots (35 mph).

I just don't know what the max RPMs I should be running at.

Boat is a 1987 Mako walkaround.

Thanks

Rob
www.sharkfighter.com

[Proheat]

Motor Specs
Manufacturer: Yamaha
Model: "300 V-Max 3.3L HPDI"
Year: 2004
Horsepower: 300.0
Cylinders: 6
Type: 2 stroke
Gear Ratio: 1.75:1
Min WOT RPM: 4500
Max WOT RPM: 5500
Spline Count: 15
Drive Type: Outboard

[SharkFighter]

Thanks That will help.

[WildLines]

when we had 300 HPDI's we found the key to getting the better fuel #'s was to not lug the motors. We had our boat propped to turn 5500 RPM trimmed out with a fishing load in flat water, it would turn 56-5700 light. We also found mounting the motors higher than the factory helped, these items increased ouf Fuel #'s by 10% accross the boad.

Enjoy.