Boat Gas Mileage
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The only direct comparison test I ever read was in SpeedBoat magazine. A 39 Outerlimits was tested with twin Illmore 625s vs twin Merc 600SCIs. The Mercs were 25+% more fuel efficient at similar cruise speeds, and then both engines burned about the same at WOT with similar top speeds. I believe that is because the twin screw supercharger is going to be more efficient at moderate loads.
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Data I've got from ilmor showed the following fuel burn for 710's in a 41 ft fountain p1 boat.
18.6 gph @ 4k
26.3@5k
47@ 6k
These are of course, per side
These were similar to what my 525's were at wot, and the ilmors are turning more rpm's. 6350 vs 5300
At 4200 rpm's in my 32 skater I'm going rt around 90 mph, which works out to about 2.25 mpg @ a 90 mph cruise. pretty good , I think!
18.6 gph @ 4k
26.3@5k
47@ 6k
These are of course, per side
These were similar to what my 525's were at wot, and the ilmors are turning more rpm's. 6350 vs 5300
At 4200 rpm's in my 32 skater I'm going rt around 90 mph, which works out to about 2.25 mpg @ a 90 mph cruise. pretty good , I think!
Last edited by stainless; 12-26-2010 at 12:35 AM.
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I just found another test that listed 525's at 60.15 gph Per side @ 5000 rpm's
Tested in a baja 40
(just google fuel consumption for mercury 525s @wot)
For the ilmor, that's 43.7% of the 525 consumption @5000 rpm's .
I know it's apples vs oranges comparing a 41' fountain p1 boat vs baja 40 pleasure, but you get the idea at least.
Tested in a baja 40
(just google fuel consumption for mercury 525s @wot)
For the ilmor, that's 43.7% of the 525 consumption @5000 rpm's .
I know it's apples vs oranges comparing a 41' fountain p1 boat vs baja 40 pleasure, but you get the idea at least.
Last edited by stainless; 12-26-2010 at 12:53 AM.
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i have yet to fuel scan my ls7 small blocks remember when i say small blocks there 450 cubic in but so far they are super fuel effeicent im mean i almost thought my fuel gauge was not working its that awsome i knew it was going to be good but i didnt think it was this awsome its unbelevable
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The only direct comparison test I ever read was in SpeedBoat magazine. A 39 Outerlimits was tested with twin Illmore 625s vs twin Merc 600SCIs. The Mercs were 25+% more fuel efficient at similar cruise speeds, and then both engines burned about the same at WOT with similar top speeds. I believe that is because the twin screw supercharger is going to be more efficient at moderate loads.
Allen
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i have yet to fuel scan my ls7 small blocks remember when i say small blocks there 450 cubic in but so far they are super fuel effeicent im mean i almost thought my fuel gauge was not working its that awsome i knew it was going to be good but i didnt think it was this awsome its unbelevable
Last edited by Smarty; 12-26-2010 at 12:43 PM.
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Another entertaining thread...
![Drink](/forums/images/smilies/drink.gif)
![Drink](/forums/images/smilies/drink.gif)
![Evil](/forums/images/smilies/evilB.gif)
Below is something that I posted last September in another thread:
I just filled up last night.....and did calculations that I probably shouldn't have.
I went 136 miles (95% of this was 3600-4000rpm's) in a 38 Cigarette with 800's
I burned 171 gallons
That is .8 mpg...or 1.25 gallons per mile
70 gallons of AvGas @ $4.70 per=$330
101 gallons of 93 octane @ $3.279 per= $330
So, that's $660 to go 136 miles for a grand total per mile of .....................$4.85 per mile.
Like everyone else has said, the gas isn't the expensive part.....breaking chit is and everything breaks eventually.........if you use it
![Big Grin](/forums/images/smilies/biggrin.gif)
![Drink](/forums/images/smilies/drink.gif)
![Evil](/forums/images/smilies/evilB.gif)
![Big Grin](/forums/images/smilies/biggrin.gif)
![Drink](/forums/images/smilies/drink.gif)
![Evil](/forums/images/smilies/evilB.gif)
Below is something that I posted last September in another thread:
I just filled up last night.....and did calculations that I probably shouldn't have.
I went 136 miles (95% of this was 3600-4000rpm's) in a 38 Cigarette with 800's
I burned 171 gallons
That is .8 mpg...or 1.25 gallons per mile
70 gallons of AvGas @ $4.70 per=$330
101 gallons of 93 octane @ $3.279 per= $330
So, that's $660 to go 136 miles for a grand total per mile of .....................$4.85 per mile.
Like everyone else has said, the gas isn't the expensive part.....breaking chit is and everything breaks eventually.........if you use it
![Big Grin](/forums/images/smilies/biggrin.gif)
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Happily retired and living in Heavens waiting room.