That's just what I was told by the previous owner of the car. He owned Mike's speed and auto in Washington NJ. The car was built by him, he said he bought the short block over the counter from GM. The heads were bought separate, which are 186 castings with big valves, they were machined for dual valve springs. I have the oil pan off and the crank number is correct, the block stamp number is ce9a24283.