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Old 08-04-2012, 08:06 PM
454C10 454C10 is offline
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FYI, more overlap doesn't "bleed off a little cr". The engine isn't even trying to make cylinder pressure on that part of the 4 stroke cycle. The intake valve closing point is what effects the "bleed off", as this is the only part of the 4 stroke cycle that the engine is trying to make compression. And long duration cams will have a later intake valve closing point. In fact, the intake valve will be open long after the piston is on the rise to make compression, thus reducing the effective compression stoke which reduces cyclinder pressure.