Twin 350 Fuel consumption

[randerson]

I am purchasing a 1988 SeaRay 270 Sundancer, 10 foot beam with Twin 260's. Final paperwork will be completed when the Marine Survey, mechanical inspection and sea trial are complete and satisfactory.

I'm curious about optimum fuel consumption. I assume somewhere around 3,000rpm (at cruising speed) or very low rpm. I know river current etc play a part in this but I am looking for an average. If anyone has experience in this area, I'd greatly appreciate your feedback. Thanks!

 

[Kevin Smith]

I am no expert about this but here is my experiences and hope they are helpful-

The F 32 Trojans burn around 17-22 gph while cruising at about 20 knots in fairly calm seas with no major current from tides or rivers. Of course this is a much heavier boat and there is always the issue of prop pitch, alum vs SS props, etc.. This is general information heard from several owners.

While performing a survey and sea trial on a 27' Phoenix Offshore Tournament with twin 350 (300hp) fuel injected engines, it would run at almost 40 knots and consume 52 gph & at 3,000 rpms about 25 knots it would consume 26 ghp. These results are based first hand readings from 2 fuel management systems on board during the sea trial. This boat probably weighs a lot more than the Sea Ray.

Both of the models mentioned above have straight shafts, heavy boats and yours probably has outdrives? But a fuel management system would be very beneficial and likely pay for it's self. It would be very interesting to know how your model does?

Kevin Smith, Richmond VA
1991 250/270 Weekender, 454 CI, 330 HP, Bravo II

 

[randerson]

Thanks for your input. Yes, mine does have outdrives and they are older motors, but I was thinking that it would be somewhere between 1 and 1.5 mpg at cruising speed. I really appreciate your input . . . I see you respond to many inquiries on this forum. That's just great! Keep it up!