well learned something new today, although I guess I should have know this. Got some head gaskets from Flatout with the combustion chamber and valve pocket area undersize so I could fit them to my block(flathead ford V8). I matched one up to a spare block, same bore, and then to my valve relief area on the heads I am going to run. Well, put the gasket on the motor in the car and the bores are off by .050 or more. Seems the bore spacing is just not the same. Passenger side is worse than the driver's side. I guess I would have to make the gaskets, block and heads a matched set from the start.