Cheap 318 performance mods.

cheapest, easiest and best bang for your buck is to recurve the distributor. :)
I run early 318 heads with small valves 208/214 delta cam, and 9:1 in a w100 @ 4700 ft. 800 Rochester on a stock spread-bore. Save your money. Pulls from the bottom and hold 85on the freeway with ease 29” tire 3:55. 302 heads aren’t magic.