BMW 1800 Ti/SA 'homologation specials' were campaigned successfully by the works team in the mid-1960s, most notably by Hubert Hahne and Rauno Aaltonen.

The 'TISA' was based on the 1800TI (Turismo Internationale) whose immediate ancestor had been the 1500 saloon.

Introduced in 1961, the 1500 was powered by a four-cylinder, overhead-camshaft engine with cast iron block and alloy cylinder head, which would evolve into one of the foremost competition units of its era.

In its ultimate, turbo-charged, Formula 1 incarnation this extremely versatile little engine produced up to 1,500bhp in qualifying trim, powering Nelson Picquet's Brabham to the Drivers' World Championship in 1983.

Built to meet the then current touring car race regulations, the limited edition 1800Ti/SA (Sonderausführung – special edition) came with a 130bhp engine (20bhp more powerful than that of the stock 1800TI) incorporating a counter-weighted crankshaft, larger valves, 10.5:1 compression ratio, competition camshaf...