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Old 05-26-2007, 12:51 AM
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Sport_Pilot
 
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Default RE: os 70 surpass vs os 61 fx - fuel consumption

ORIGINAL: hungryandbroke

So I am assumimg that if I compare a .61 2 stroke to a .91 4 stroke the fuel comsumption would be about even for the amount of run time?

Also, what size engine compares to a .91 4-stroke? A .61 or more like a .75?

I'd like to know.

thank you,

charlie


No actually the rule of thumb is getting a bit antiquated. Four stoke engines have become more powerull since this was done so the .91 may use a bit more fuel but even more power. Still I think it is close enough to use. The old rule of thumb is that a four stroke must be 1.5 times the displacement for the same power, but It is a bit below that now. So I think the .91 four stroke is now closer to the .75 than the .60, but still fairly fuel efficient so the fuel used is between that of the .60 and .75.

charlie