Any body know if the early oil pans were interchangeable threw the years I have a French block from Sacramento speed I have the pan that has a back part that houses the flywheel and starter i think it's a latter one cause it has the smaller oil drain plug and would the difference be the bolt pattern or other things please advise if you can
Your pan fits from about 35 through the 48 flatheads, US production. I think it will fit the French block too. There are a ton of variations over those years, but the main flange where it bolts to the block should fit fine. Only thing that might cause trouble is if you are trying to fit it into an early ch***is with a stock wishbone and a low stance. Also, if using the later oil pump you will need to cut the windage baffle out.