What is this?? 318 stroker??

Well here are my findings. Got the camshaft out and ran the numbers on the back end. For the life of me I cannot find anything on the net telling me what the specs are, or even the maker! The number is 51035?? I also pulled one main cap off. I measured the main journal and it is 2.50 on the money. The number on the bearing is MB2283P and its marked STD. So I guess it really is a 318!! Lol. I'm really stumped by the cam numbers. Anybody know what this is?? Thanks for any help!