90 over 318 Head Gasket info needed !!

Good point on the Mopar cast cranks as well. I once had a gouged out 400 B crank that I used as a "hammer' to reduce other pieces of bad or unwanted cast iron from the Ford and GM foundries to make it easier to load for scrap. That crank never did break, no matter how hard or high it was dropped from, but the stuff it was hitting sure did!
Direct Connection book has foot notes saying cast casts were used in Competition etc.