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      01-23-2008, 10:47 PM   #7
T Bone
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Quote:
Originally Posted by lucid View Post
Rotational inertia is just another type of load the engine experiences. It is not any different than hauling a trailer, climbing a hill, or opposing drag in the sense that they are all loads the engine needs to balance, and overcome if it is to accelerate. An engine experiencing less "total" load will accelerate/rev faster.

Understood.....using the heavy vs. light crankshaft example below....we are talking about the rate of change in revs. At a steady RPM, the only thing the engine is fighting is internal engine friction (plus the load on the drivetrain). At a steady RPM, it is not dealing with the inertia of say heavier components.

When constantly changing RPMs, the air-fuel charge would be better used to accelerate rather than overcome inertia caused by heavier internal parts.

Not trying to argue, I would like to get a better understanding....
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