Strange 318 Block
The racing version of that casting number, the X-block had distinguishing features like the X cast in the block, the front cover area has more meat diagonally across and there is more meat in the main web casting. These are the areas you should check on the 318 block you have. I do not see the thicker main web indicating it is a stock 318 block in my opinion. See aftermarket X-block pictures below.
The racing version of that casting number, the X-block had distinguishing features like the X cast in the block, the front cover area has more meat diagonally across and there is more meat in the main web casting. These are the areas you should check on the 318 block you have. I do not see the thicker main web indicating it is a stock 318 block in my opinion. See aftermarket X-block pictures below.