Today, dollar for dollar, is the 318 faster than the 340 ???

Well first off it doesn't cost $1200 for a roller cam setup in a magnum or a 340. You can easily build a good bottom end for around $1200. Nothing cheating out here it is what it is. Then get some magnum heads get a touch up on the valves. And pick a cam around $300. Nothing el'cheapo about it that's what it costs. So guess I'm trying to figure out why you think it cost $5000 to build a worthy engine?

Heck go get a reman magnum short block and throw a cam in it