318 build. what would you do?

Me and my son have 76 darts,I have a 360 and my son has a 318.we have about the same amount of money in our engines,just different combinations but close.The time difference in the quater mile is .004 of a sec.
I get 12.91 he gets 12.95 and he gets better 60 foot times,CI is not every thing.