_Static_ compression selection is dictated by available fuel octane and
camshaft selection. _Dynamic_ compression is affected by valve timing and
overlap. So, select the cam then work towards static CR. There are some
calculators
for this floating around, I'll see if I can find a link.
A long duration cam does not build much pressure at low speeds, if the static
compression isn't raised the motor will be very saggy.
If a stock ( short ) duration cam is installed in a high CR motor, high
octane fuel will be required but the power level won't be much different than
stock
CR.
Harold
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