Just looking for a definitive answer on the subject of this swap. I know I will need 77-84 non roller equipped 302 pushrods, I know i'll need to plug the thermactor holes. My questions are: What headgasket? And i read something about needing to drill "steam holes" Any link to this process? Thanks guys
Late model head gasket and drill the steam holes if you want. I drilled my mustang because I have .060 overbore and did not want any cooling issues. And they match up with the edelbrock heads. To drill the block first put the gasket on the head and mark which steam holes match. Then lay the gasket on the block and mark where you need to drill. Center punch and step drill to size, make sure to drill straight and you may want to check what you will be drilling into. Flashlight threw one of the other water hole to see.
so you are saying that it is optional to drill the steam holes? If thats the case and I decide not to do it. Should I use the early model headgasket, or stay with the late model one?
If I'm not mistaken all the head gaskets have steam holes. And even the late model blocks don't have them drilled already. I can probly get you a picture of a block out of a 91 mustang if you want to see it.
I just put E7's on a 74 block, and used the newer head gaskets, everything seemed to line up, I'll find out for sure in a month or two. I double checked all the holes and such, everything seemed to be correct.
Here is a pic of mine in the same orientation as the one you posted on the stand Thack I can see that the holes aren't the same. Will this be an issue?
Steam holes are inbetween the main water passages. Most heads have a hole there but the block does not. To utilize the steam holes you must drill the block, and these are relitivly small holes (1/4"). The purpose is to keep water flowing around the cylinders to stop boil off. This would/could create an air pocket which would create a hot spot.
