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Old 12-21-2006, 09:43 PM
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downunder
 
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Default RE: 18000rpm on a 11x7 prop

ORIGINAL: DarZeelon
If a two-stroke engine in 'base' form is running at a VE of 80% and some kind of 'super duper' pipe increases the VE to 120%, the increase is 50%, as is approximately the increase in torque.

But this engine will now be running at a VE of 120%; not 150%,
I'll give you one thing Dar, you're a master at discombobulation .
You pluck a figure out of the air for a base VE then manipulate the figures so the end result will appear to match what you say. So what if the piped VE is 120%? What matters is how much it increases it from the best the engine can do as open faced (which means it's running 100% the best it can ever do). Taking your 80% base figure at face value, then a final figure of 120% does mean it's made the engine 50% more efficient. This 50% is in regard to its bmep (torque) and not HP. The HP increase is far more than the torque increase. Actually, as I mentioned earlier, the real increase in torque with the Bolly pipe was 57.3% and the HP increase was 227.5%.