Don't over build a 318. Without more compresion the difference will be little. I put a bigger cam in a 9:1 motor and gained .1 at the strip. It would work OK on the street but bog at the sript with the extra bite.
This thread is about swapping cylinder heads. If I need more compression, i'll get it during the head swap.
please keep in mind this 318 isn't a junkyard special, it's fully balanced with a steel crank, H beams and forged pistons with dome tops and a zero deck.
Like I said, current compression ratio is 10.2:1 with the J heads.
I could easily get 12:1 with the eddies, but I don't think that will be necessary.