Fuel economy on a 272 sr1 BB
 

Went out yesterday with a full tank (filled up next to haulover inlet) and run on the ocean for 1 hour exactly.Ocean was a bit rough so I was working on the throttles in between 2200 and 2500 rpm's at all times .60 minutes later I was idling next to pump waiting about 10 for my turn to the pump and it took 19.5 gal to fill it up again.

So is 20 gph at these rpm range ok for twin BB's

What is everybody getting with similar setups?


Regards everyone !!!,

The Formula 272 performance report says (with 7.4s and 25 mirages) 12gpm at 2500 and 19gpm at 3000. That is probably smooth water. When you are throttleing, dragging tabs, drives tucked in you are definately not running most efficient so those numbers don't really surprise me. You should try running for an hour in smoother water, no tabs, no throttleing and trimmed up a little and see what you burn. (Also I think you should try putting those 383's in but thats another thread haha)

Diego run it harder get some hull out of the water and fuel economy will increase. That boat did better at 3600 than it did at 3000

I totally agree with you conditions were not the best , do you think the brochure is accurate? will try another day, about the 383's they might be for sale soon... the 454's are running great and dont want to go crazy to gain 5 or 6 more mph hahahaha.

i will try that next time , might go to Bimini with some friends soon , do you want to come down ??? eheheheh.

That sounds amazing!!!! Let me know when you're thinking!

You must mean gph....not gpm!! LOL

Hey diego

Just curious what kind of speed are you getting at those rpm's? I'm still trying to kind of figure out my best cruising Speed/mileage to. I usually cruise at about 2800 rpm's, K planes at 3-4, Drives out 1 - 1 1/2 and doing 34-36 mph..... Last time i checked i went 35 mi.and used .....i think around 21-22 gal. Oh and i start out with a full tank and 3-4 people

Lugging these boats around barely keeping them on plane is hard on everything!!! Run the boat! Tabs up drives around 3, and 34-3600 rpm roughly. May need to adjust slightly from that but you need to get the boat up and out of the water.

Diego...as Red says...get it running out 3500 RPM, trim it watching the GPS. Where you want to be is just short of where you bring the secondaries in. That the beauty of mechanical secondaries...you control it, not some phantom vacuum signal opening an air valve.

I think you are focused in very well for your rig.

Here my Thing ...I go out to the sandbar 60% of the time to hang out (10 mi. round trip) i want to in joy some Cruising Time...

[QUOTE=sprink58;3976285]Diego...as Red says...get it running out 3500 RPM, trim it watching the GPS. Where you want to be is just short of where you bring the secondaries in. That the beauty of mechanical secondaries...you control it, not some phantom vacuum signal opening an air valve.

I think you are focused in very well for your rig.[/QUOT

yes I am trying to figure out the most efficient cruise speed , btw John , what do you think about Bimini? that should be fun ...

my sandbar is 1/2 mile round trip hahaha lucky , ask LIL RED he's been there with us. When I want to cruise I just go down to south beach thru the ICW or Ocean depending on conditions.
BTW at 2300 rpm I am doing around 30 mph.

I know it's a lot of expense to do it but I sure would like to see what the GPH on yours and mine (I'm 27 MPH at 2000 RPM!!!) with a Flow Scan would be running like that...got to be getting down near 10~12 GPH.

[QUOTE=Diego9040;3977146]I am almost ready...get my first oil change done, repair some lights, install VHF, etc. and I'll be ready. Maybe in a month~6 weeks.

You, Tom in his Baja, me, who else? JasonMD with the Top Gun might be up for a shake down with his. We really should take some pics of these old Formulas over there and send them to Grant Porter at the factory!!

I can see the caption: "Vintage Formulas Cross the Gulfstream...The Formula Legend Lives..."