I was wondering if anyone has used a 9 head gasket on a 8. i know the 9 is thicker and will raise compression. I read that 2 holes will need to be drilled for water passages. I'm just curious if anyone has actually drilled the holes and used the 9 head gasket on there 8

 

A thicker head gasket raises the head, increases cylinder volume, and therefore lowers compression. I had to run a 9 gasket on the 8 block / head of my old Buschur motor that had been machined so much the piston contacted the head at TDC. Drill out the two holes for the coolant passages, as you pointed out, and you're good to go.