318 rebuild/upgrade

The Magnums have a smaller chamber thaan the 302s IIRC, but not by much, and the '68 318 head has one smaller than both I think. So, I'd plan on using the MP thin head gaskets too. I would choose a better cam than one made by Edelbrock if it were up to me. And dont forget, with Magnums, you need AMC lifters, and drilled pushrods to keep the top end oiled. So if you can purcahse just the cam, and then lifters, you'll be better off.