Anyone ever used one of these? Back in the 60's they were considered hot stuff! I was thinking of getting one for nostalgia, but many years ago I once had an MSD capacitive discharge system, and to me, it really didn't seem to do anything! Other than the cool factor, does the Mark Ten really work?
We've had a couple of them come into the shop over the decades, both were getting long on the tooth and starting to have problems. As we do now, we sent the boxes to our ignition professional, whom swapped the internals for an HEI module, so they still look like a Mark 10, but have new electroncs inside them.
I had one of them I built from a radioshack kit same unit as delta mk10b
it had a switch were you could enable or disable the unit. the mine did have an effect - the idle rpm's would increase slightly when the unit was switched in never had burned points since they were just used to trigger the unit.
There used to be a forum where a guy documented some interesting mods that increased the performance of the units but I cant locate it at the moment if I find it ill update here. If you have a unit its probably best to replace any electrolytic capacitors inside as these things are over 30 years old
EDIT: here is the link to that document about modifications starts around page 48 note this document has some very detailed and technical information about ignition circuits and operations
Main takeaway is that these cdi units work better ( more energy deliver to the spark plug) with a transformer type coil the regular points style coils work but not as much energy because of the way the magnetic field isn't coupled north to south poles as well as a transformer type coils, the later hei both in cap and external coil types are transformer design coils I think.