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Old 03-17-2013, 08:01 AM
454C10 454C10 is offline
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If you install 2 cams, both with 230 degrees of duration on the intake and exhaust but one has a 108 degrees Lobe Separation Angle LSA and the other has 114 LSA.

The cam with the 108 LSA will have more overlap and an intake valve that closes sooner. So the cam with more overlap will have lower vacuum at idle and higher cylinder pressure.

So a cam with more overlap doesn't always mean it will have lower cylinder pressure.

It is also important to look at the actual intake closing point (not at 0.050"). Stock cams tend to have long lazy ramps which also lowers pressure due to shutting the valve at the same point of a much bigger high performance cam with fast ramps.

Last edited by 454C10; 03-17-2013 at 08:07 AM.
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