Alvis designed and manufactured the 4-cylinder 1842 cc pushrod overhead valve engine which was similar to the engine of the Alvis Firebird but was, in fact, a new design. Alvis also designed and made the 4-speed gearbox which had synchromesh on the top 3 speeds.
Many of the other components were outsourced to other suppliers in a bid to cut costs.
A total of 741 cars was manufactured, and in 1945 the 12/70 was replaced by the Alvis TA 14 but much of the 12/70 lived on in this post war model.
| Classic production cars
| Classic racecars
| Classic concept cars