spandit:
MegaJolt (and MegaSquirt) need a trigger wheel on the crank.
They're very flexible, and can be driven off points just as well - but I wouldn't recommend it because the resolution would be relatively poor and it would be subject to all the mechanical inaccuracies of the existing system. You would definitely need a trigger wheel if you went for an EDIS based coil driver, and there would be considerable advantages to doing that. But if you're going for mapped ignition in the first place, it really makes sense to get the additional resolution of a trigger wheel. (If it's not worth the effort of doing that, is it really worth the effort of implementing mapped ignition at all?)