I have considered converting my B21A Engine's conventional Bosch JFU4 0 231 170 284 Distributor to a modified B21E JGFU4 0 237 002 017. I have a clean spare B21A Distributor and two recently acquired B21E Electronic Ignition "Systems". I removed the Centrifugal Flyweights, Springs, and Vacuum Advance, from the B21A Distributor and installed them into the B21E Distributor. Those things modify the Advance Curve. The Advance Curve is different between the B21A and the B21E engines. So, my thoughts are to make the B21E Distributor have the same Advance Curve as the B21A Distributor. Tomorrow, I will remove my conventional B21A Points/Condensor Distributor and install the modified one, using the B21E Coil, Ballast Resistor, and Control Module. I will likely set Timing at B21A recommended 10 degrees BTDC. I will start with the Bosch W7DC, because that is what I have installed.

Consulting with a couple Bosch Reps it was suggested I use Bosch W200 T30 or their equivalent Spark Plugs, recommended for the B21E and could gap them as much as 1.1mm. They suggested the engine would not falter, as with the old-fashioned Points/Condenser Distributor and would have a much better and consistent Spark under all conditions. I think that might equate to better fuel economy.

I will let you know how I go.