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

318s suck, I would never advise anyone to waste money trying to wring any amount of power out of one, it's not worth the expense. It's like the loony Slant 6 guys, these types have a Napoleon complex. Get over it, buy a 360, stroke it to 422 and be happy. Life is too short to waste money trying to prove a point that no one cares about. If guys want to prove they can do it then go for it, make us all believers but stop making weird arguments trying to convince people otherwise.
If you don't think a 318 can run, then you may be the one stuck in the 80's. There are some seriously fast small cube motors now, welcome to 2021. Not being rude or controversy. There was a guy right here on FABO that offered to races those 422 for $$$ with his 318. We are away from the discussion, just say'n....