Kb190 Pistons And Eddy Heads
This may not help so much, but then again it might.
I was running zero deck KB-107's+.030 (Flat tops, 2 valve reliefs) with Edel. heads. The regular ones, not the 340 units. The gasket I used was .039 thick, a Fel-Pro. No issues with pistons slappin the heads.