Oh boy! I did know a thing or two about the Cubs! The 200cc Tiger Cub was first built in 1953. That type of block, a single piece casting, was built until 1959 or so. After that, the vlocks were split down the center to make a two piece crankcase. The first series of engine would be legal. The rulebook says something along the lines of 'like parts' that make the '56-'59ish parts legal since they are the same part with the same casting number. I have alot of money into the books, parts list, manuals, etc that I have no need for if your interested.
