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Old 02-07-2014, 07:52 PM   #95
strat61caster
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Originally Posted by chrisl View Post
Most of that energy is recovered on the expansion stroke though - the air in each cylinder is basically acting as an air spring during the compression and expansion strokes when the engine is running this way.
You're right, I neglected that. That would be an interesting exercise but I've done enough math on this forum

Generally higher compression engines mean more work is done on the fluid which is why I figured engine braking is largely a function of the compression stroke over other factors, it generally doesn't cost nearly as much energy on the intake and exhaust strokes. In any case, I still think it's erroneous to attribute engine braking mostly to the intake stroke.
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Originally Posted by Guff View Post
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