[rotorwrench]

There is not really any way to put load control on a mag unless the whole mag rotates or at least the magnet rotates along with the points. Centrifugal impulse couplings are not for anything other than starting aids. They retard the spark until the engine starts and then the centrifugal weights cut the starting aid out of the system. Mags have to maintain proper internal timing to keep E-gap at the point opening or they won't run. You move the points plate and the internal timing is off.

The old Motorcycles that had load control moved the whole mag to change the advance for load control. The old S2R Lucas mag on my 58 Indian Enfield just has a little impulse coupling for starting and then runs full advance all the time. Aircraft mags work the same way. They will run OK but their is no load control. It's just full advance all the time.

Perhaps they have a model that moves the magnets along with the points but most of the old Vertex mags are the Locked type. The Lucas K2R Cycle mag was set up for adjustable advance but it was manual and worked by having the coil built into the rotor with fixed magnets. That way they could move the magnets and the breaker points a little bit. P-Mags are starting to show up on aircraft now days and they are electronically controlled mags much like an electronic ignition. They have a programmable advance curve but they are basically a little alternator with an electronic ignition. They are not a true magneto that runs off the building magnetic field in the coil which inducts as the breaker points open at E-gap when the magnetic field reverses due to rotation of the magnet.