Originally fitted with a 20x5.00 (500-20) crossply tyre.
The Firefly and Firefly 12 saloons, roadsters and touring cars effectively replaced the 12/50, and fitted into the popular 1.5 Litre category of the time. The Firebird was a developed and restyled version that continued Alvis's reputation for well-built chassies clothed to a customer's requirements by quality coachbuilders.