The MG TA replaced the PB in 1936. It was an evolution of the previous car and was 3 inches (76 mm) wider in its track at 45 inches (1,100 mm) and 7 inches longer in its wheelbase at 94 inches. The previous advanced overhead-cam inline-four engine was now not in use by any other production car so it was replaced by a more typical MPJG OHV unit from the Wolseley 10 but with twin SU carburettors, modified camshaft and manifolding.
The engine displaced just 1292 cc, with a stroke of 102 mm and a bore of 63.5 mm and power output was 50 hp at 4,500 rpm. The four-speed manual gearbox now had synchromesh on the two top ratios.
Like the PB, most were two-seat open cars with a steel body on an ash frame, but it could also be had from 1938 as a Tickford drophead coupé with body by Salmsons of Newport Pagnell or closed "airline" coupé as fitted to the P type, but only one of these is thought to have been made. It was capable of reaching nearly 80 mph (130 km/h) in standard tune with a 0–60 mph time of 23.1 seconds. Unlike the PB, hydraulic brakes were fitted. Just over 3,000 were made.
Source: Wikipedia, 2011