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Old 10-09-2012, 11:44 PM
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Quote:
Originally Posted by vinniekq2 View Post
A small cam is not rocket science.I like cams with lower intake centrelines for stock compression engines.keep the duration short,220 or less and lift moderate.Yes ported heads work better.The heads you have would work better ported.dont expect huge gains in power just changing 1 item,,,
You cannot intelligently choose a camshaft for a motor until you know the static compression ratio. You might just as well write the candidates on little pieces of paper, tape them to the wall, stand back and throw a dart.

From Crane Cams....
"Why is it necessary to know the Compression Ratio of an engine in order to choose the correct cam?
The compression ratio of the engine is one of three key factors in determining the engine's cylinder pressure. The other two are the duration of the camshaft (at .050" lifter rise) and the position of the cam in the engine (advanced or retarded). The result of how these three factors interact with one another is the amount of cylinder pressure the engine will generate. (This is usually expressed as the "cranking pressure" that can be measured with a gauge installed in the spark plug hole.)
It is important to be sure that the engine's compression ratio matches the recommended ratio for the cam you are selecting. Too little compression ratio (or too much duration) will cause the cylinder pressure to drop. This will lower the power output of the engine.
With too much compression ratio (or too little duration) the cylinder pressure will be too high, causing pre-ignition and detonation. This condition could severely damage engine components."
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