What have you done today with your Austin Seven

[Bob Culver]

The consequent very high volts hugely stress the coil and probably condenser. Although I have done it many times over the decades (and i can recall my father demonstrating when I was very young) operating with large spark gaps can be destructive.
(A Jowett club Javelin with a very, very  low mileage engine out of a boat, recently melted a  hole in a piston. The only evidence of possible cause was a carbon track between successive cyls on the distributor cap. We think a disconnected lead had caused early firing on an adjacent cylinder)