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      05-04-2013, 06:53 AM   #44
CanAutM3
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Quote:
Originally Posted by mkoesel View Post
In all modern automobile combustion engines only one cylinder fires at a time. So I was assuming the same for my hypothetical engine examples.
It is true that only one cylinder spark plug "fires" at once. However the power stroke, the time positive cylinder pressure applies force on the piston, lasts about half a revolution. So for engines with more than four cylinders, power strokes will overlap.

Quote:
Originally Posted by mkoesel View Post
Agree. But like I said, peak torque is still ultimately bounded by torque at any given instant, which in turn is a function of the force at that instant.

It's just like my last example. Sure you can get a lot more finger taps in than hammer swings over a given period of time. But you still never make any significant dents in the sheet metal.
The sledgehammer example is not really representative because it refers to an impact. If you have 100 fingers pushing on a object with 1lb each, it will yield the same force as a person leaning with his shoulder on the object with 100lbs.

Since peak torque is measured for a given RPM, I still think torque of the engine pulses need to be averaged to properly reflect an engines abilities.

Last edited by CanAutM3; 05-04-2013 at 07:03 AM..
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