Career
He entered the motor industry through his company Speedex Castings and Accessories Limited., based in Luton, that manufactured and sold tuning parts for Austin Sevens, based on Marsh"s successful Speedex750 racing special. Founded in 1959, the company was continued by Jem"s son Chris Marsh, until it was taken over by Canadian Tony Stellinga, and continued to produce automobiles until 2008 when it ceased production.
