Another 273 cam question.

The compression is pretty simple . Measure how far in the cylinder your piston is when it is at tdc . then calculate the volume of the recesses in the top of the piston, then have the head cc's then put all the inf into the calculator below and see what it is.

Compression Ratio Calculator - Wallace Racing

if you are interested in how much compression it currently has, simply do a compression test n 2 cylinders . if it is less than around 140, increasing the compression will be helpful.
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