its gunna be fine im tellin you i ran b16(pr3) pistons in the old setup witha shaved head it jumped 7 teeth in the wreck and no valve-piston contact look at my avatar thats some dome son 12.5:1 pistons shaved head i know mine will be ok you have nothing to worry about... i dont think you comp ratio is going to be 12:1 im thinkin like nothing over 11:5 maybe a lil lower mine will prob be like 12.8:1 and my pistons come to a point.

ps> run the arp rod bolts its worth it they are cheap too if you wanna rev a little higher

how much was ur head shaved?