Quote Originally Posted by kevinp
ghosthunter, could you explain your point further? logic tells me that the volume of fuel that is injected into the combustion chamber per revolution of the engine will be the same if its running at 1000rpm or 6000rpm. afaik, the increase in power at higher revs is caused by the corresponding increase in revolutions of the crankshaft and its momentum.
in theory, 1000rpm & 6000rpm should only differ by comsuming six times more fuel for the same amount of time.

in reality, there are inefficiencies to consider. Like the volumetric efficiency of the fuel system and air-intake. Example, if the air-intake is sufficient at 1000 rpm, it might not be sufficient at 6000rpm and would cause the engine to run over-rich. The opposite would happen if the fuel system is not sufficent at 6000 rpm, the engine would run very lean and might lead to detonation.

Also as mentioned, fuel consumption under no-load and loaded conditions are different. Thats why there is such a thing as "brake-horsepower" rating. A free-reving engine (with no load) reving at its redline is not producing its maximum power, its just reving very fast.