That's something I was thinking of doing, using case half(s) and crank. I would want to take the connecting rod off the crank. Add a multi grove v-belt pulley and a variable speed motor for variable RPMs. Make a degree wheel out of an old CD/DVD. This would aid in building an AC alternator, like the "mini gen" for testing and working out as many bugs as possible. I like to do as much as possible by myself using what I find to work with. I just don't have a junk engine to work with. Donations welcome. LoL. Anyone willing to donate a junk crank and case I will put it to good use.
I'm building a timing light circuit now on a bread board, if it works Ill make a pcb and a portable unit.