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Unread 08-05-2011, 07:29 PM
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phatdaddy phatdaddy is offline
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Join Date: Mar 2003
Location: south of I-10
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and old rule of thumb for carbed outboards is 10% of hp per hour & back off 20 % rpm and cut fuel comsumption 15%, so,

150 hp = 15 gph @ 5500 rpm & at 4200 rpm 12.5 gph.

i have a 94 150 merc and i avg 2.5 mpg,so if figure with a 60 gallon tank a 120 mile range. i have no fuel guage, so i set my trip log on my gps and fill up when i get close to 100 miles and usually i can tell you within 3 gallons how much it will take.
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