If i were you, i would just throw the Y8 head on the CRX A6 block and the y8 tranny. It'll bump your compression up to around 10.5:1 instead of the sorry dead slow stock vtec with 9.3:1. A6 pistons are flat top i believe and the y8's are little slope .

Better yet goto a junkyard and snag a set of p29 pistons off of a 88-89 integra 1.6 dohc + y8 head= 13.1:1