Think about it;
there is nothing a performance 318 can do, build for build, that a 360 can't do better. Build for build, and gear for gear, a 318 can edge out a 360 in hiway economy; mostly because of internal friction , in dragging slightly bigger diameter rings, slightly further up and down the bores. And maybe you can find one or two other legitimate reasons but those will be small contributors.
But then, build for build and gear for gear, that same 360 will kill the 318 in performance.
