Why are 318's low HP and torque?

Take .010" off the block and .010" off the open camber heads .021" gasket and those 1.741" pistons got yourself 9.1:1 CR and .010" off 302 get almost 9.5:1 CR that's ain't too bad of a mod. I'm gonna do that one to my 5th Ave and port the heads and step up to 268 cam.