Mercury 150 Fuel Mileage - 1971 20' SF

[Blue_Heron]

Originally Posted by Bigshrimpin

150 XRi is a 2.5L. You need to prop the boat so that the motors turns 5800 WOT with average load. I suspect you can improve your performance quite a bit by raising the motor a few holes and finding the right prop. 5100rpm with a 19P is lugging the motor down too much and you'll get crappy fuel economy and performance. I could crack 40mph on my 20 MA with a 150xr2 and that's a 2.0L motor. The super long 150 tuner limits the top end on that motor a bit, but you should be low to mid 40's with a 2.5L 150.

What Tim said x 2.

The anti-ventilation plate should be at least an inch above the keel. Mirage is a good prop for that boat, but 19P is too much prop. Try a 17P if you can find a loaner.

Dave