318 build up
I have built some real nasty 302's. It takes high copression, big cams, and tons of RPM's. The 302 SOUND nastier because of the short stroke too.
The 318 will make the same power a few hundred RPM lower. The 318 heads breath better, I think, common to common, mostly, to get apples to apples, you woul dhave to put a 318 in one mustang, and a 302 in the other. Whats a little 5.0 mustang weigh? 200 pounds? LOL When you put a 302 say, in a truck, you see nothing but 318 tailights.
As far as the small bore, one mans hold back, is another mans treasure. I like small bores, they run cleaner, get better MPG's, carbon up less, and are less prone to detonation.