MG - MG 18/80
The MG 18/80 was the larger sportscar available from 1928, using the 2.5 litre Morris overhead camshaft six cylinder engine which stayed in production to midway through 1931. It was replaced by the 18/80 Mk2 which was first MG to have a chassis built for it, rather than using a Morris chassis, but performance suffered a little due to the extra weight, although handling improved, and production of the Mk2 lasted to 1933.
Tyre size for the MG 18/80 (Mk1 and Mk2) was 500x19. Blockley makes the perfect period correct high quality 500x19 with triple stud pattern as they were when new. See full details of this period perfect high quality 500x19 tyre below: