I seem to recall that one of the Tiger Club's Turbs was modified with a different ignition system, might have been 'PNZ.
Ah, 'JCP, 'PBZ and 'PKZ also had the bulge early on - early Rollason Turbs had a 1200cc VW engine but later on the Ardem modified 1600cc. PNZ lost the bulge later and has the Ardem engine, so I would imagine the bigger engine had a different installation.
Last edited by treadigraph; 16th Apr 2021 at 11:12.