ORIGINAL: Antique
Don't know...If the ignition has a good groound there's no reason the cap would have anything to do with it...Seems like there would be less carbon tracing in bakelite VS silicone...The bakelite cap has a metal piece that clips on to the top of the plug....
Seems like Bosch used to make some very good bakelite caps....I agree with Antique. He has forgot more than other people ever will know.