i need help with why 1 get 1.5 nmpg please

[arima]

hi everyone i own a 2005 2520 scdv and im wondering if you guys could help me get better mpg i have twin 150 yams!!!any help would be great come on big dogs help a newbe out i see you guys getting 2/2.4 how are you doing that???thanks everyone
mike

 

[captbone]

Wlecome aboard. More info is needed.

2 strokes with Carbs or EFI?
HPDI?
Four Strokes?

What size props?

 

[arima]

they are four strokes and im not sure what size props they are i will check tomorrow thanks for the come back..
mike

 

[John_Madison CT]

Yeah, something isn't right. I hear closer to 2mpg with that set up.

 

[zebpwgc]

I have a 2520XL with twin 200hpdis. i get about 1.5-1.6 NMPG offshore loaded up. Thats running about 24 knots @ 3500 rpm.

remember this is Nautical miles per gallon. Most perfromance specs will list MPG not NMPG. 1.5-1.6NMPG is equivalent to 1.73-1.84MPG.

 

[DaleH]

Yup, (nautical MPG x 1.15) is roughly statute MPG.

MPG is also higly dependent of tides, wind, sea state and trim tab use, which I have proved through testing, using a fuel computer, to add 10-20% effficency or remove 20% or more depending on angle of deployment.

Check your prop pitch. You want those Yummies spinning a wheel which puts them 200-300 RPMs off of max WOT with normal gear, 2 people, and 2/3rds to 3/4 full of fuel.

'Tis better to be under-pitched than over-pitched with these big girls we run.