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I was reading a magazine article about an engine combo and the cam was installed by getting the highest cylinder pressure. I mean it was advanced and or retarded until the highest pressure was obtained and that was the determining factor in deciding the amount of advance that was used. How was that done and is that a good idea on a street/strip engine? The cam was a custom grind with about 245 degree duration at .050, but low lift of .510.
 

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Mike is right. Advancing the cam closes the intake valve sooner on the compression stroke and causes the cylinder to build more pressure even though the engine may make more power and torque with the cam not advanced. The problem is that compression tests are done at 200 RPM and the results have little bearing on what may work the best for volumetric efficiency when RPM induced factors such as high port velocity, air flow inertia, and resonance tuning are factored in to an engine spinning anywhere between 3000 and 9000 RPM.
 
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