Old 08-20-2011, 05:36 AM
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Default RE: DX8 Throttle Curve and DLE 30ccCan't get it right....

You're speaking of "peak" Volumetric Efficiency. Yes it "generally" occurs right around torque peak. Remember torque peak is usually (not always) a fair amount lower than HP peak. Sometimes several thousand thousand rpm's less. In order to make that upper rpm number and the added HP to go with it more fuel and airflow through the engine are necessary. This probably ain't the right place for too much on this as I don't want to hijack the OP's thread but if we want to calculate the CFM (Cubic Feet per Minute) for a 4 cycle motor we can multiply the cubic inch displacement of the engine by the maximum rpm and divide the result by 3456. Then we multiply the results by the volumetric efficiency of the motor. I don't have the formula for a two stroke but this formula gives the information showing that rpm's are part of the airflow requirements of an engine.