Porting Question

72 c +or- 2cc's unmilled.

I want to
Know gear ratio tire size and if your running a stock converter. Dependent of these factors would sway me in what head I would use and how to work it or not.

Truth be told, a decent gear ratio and wide tires with the stock head will get you low 15's.
A bo blending and the 360's valves in the 318 head is a real nice upgrade and out power the J head as cast. The problem with the J head is it is a compression dropper. Not that the cam needs much to begin with.

How many cc's in the slug?