Why are 318's low HP and torque?

monkey said

I am a new member to the site and I've read this thread over a few times. I have one question but first let me give you a little back ground info. I have a 73 swinger stock 318, with headers, MSD ignition, Edelbrock intake, Edlebrock 600cfm carb, and 3.55 gears, I would like to install a 262 cam, would the 302 heads be a good addition ? I have a chance to pick up a set cheap.

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302 heads flow about the same as every other 273/318 heads but will bump your .5CR which might give you 5-10hp on a 300hp engine, with a thin gasket and a little milling to get 9:1CR which might get you 10-20hp but more important would allow you to go with larger cams. Not saying its not worth upgrading to 302 but not a must upgrade 262 cam, $ for $ not the most cost effective upgrade unless moving up to larger cam.