Fuel consumption

jddens · Post by **jddens** » Wed Aug 22, 2007 5:43 pm

I have a general gph question. My 30 foot Sea Raider seems to have 2 sweet spots for cruise speed. 3100rpm at about 18knots and 8 knots at about 2100rpm. Pwr is Vortec throttle bottle fuel injected 350's.

All things being equal, which speed should be most fuel efficent?

Thanks!

rossjo · Post by **rossjo** » Thu Aug 23, 2007 2:03 pm

8 @ 2100 is < hull speed = efficient

thelast322 · Post by **thelast322** » Mon Aug 27, 2007 9:33 pm

Efficiency can be measured by how much distance you can travel on a specific amount of fuel. Simply Miles per gallon. For example if you choose to cruise @ 2100 rpm and speed is 8kts you have to figure what your burn rate is. Say 350"s burn around 4gph a engine @ 2100 rpm then your average nmpg is 1 nautical mile a gallon.
Look at boating magazines test boats fuel comsuption Charts and you could get a better idea.

I have 350 crusaders in a f32 and find the boat to be the most efficent @ 3000k will push me @ 20-21.5 knots " no wind or current" on a burn rate of 8.5-9 gph per engine. The floscan intergrated with the Gps indicate a NMPG of 1.10-1.23. This drops off once the wind or current kicks up.

Will hopefully this helps you out!

jddens · Post by **jddens** » Tue Aug 28, 2007 10:45 am

Thanks for the input......sounds like a flowscan would be a good thing to have. Thanks again............