I am working on a project to control spark advance with a modified megasquirt unit that requires completely locking out the mechanical advance on the distributor. The goal is to customize the advance curve based on RPM and MAP values and maybe be able to do knock retard. Some folks who are much smarter than I am have done all of the hard work - I'm just trying to implement their recipe.

I've got a decent b18 distributor (009) half disassembled and I don't see an elegant (sturdy) way to lock out the mechanical advance on the thing. Only route I can think of is using /really/ strong springs on the mechanism but I'm not sure where to source them.I picked up a cheapo tuning kit for chevy distributors at the auto parts store but the stongest springs in the kit still allow the advance to operate to some extent. If anyone has any thoughts here I am totally receptive.