BMW
With a background in aircraft engines and motorcycles, car production started in 1928 with the BMW-Dixi, an Austin 7 built under licence, which evolved into the BMW 3 / 15. BMW then continually expanded the range with their own 315, 319, 327 and the well known 328 with a alloy overhead valve cylinder head fitted on their existing block, in a state of tune that needed minimum 80 octane fuel. The war ended up with the Munich factory destroyed by allied bombing while the eastern factory was now under communist control producing prewar copies of the BMW 327 branded EMW, as the factory had ended up in the new East Germany. The British ended up with all the relevant type 327 and six cylinder drawings which led to the post war Bristol (and Frazer Nash) being up and running so quickly.
BMW built their six cylinder 501 model in 1951, and then came out with their own new all alloy V8 engine for the 502 and 503 models, initially 2.6 litre which was later enlarged and modified to 3.2 litre, which led to the Goertz penned 503 and 507 models that were in direct competition with Mercedes road cars, with the BMW having a higher list price. The final V8 in this line was the 3200CS. The BMW engine design was sold to the USA to become the V8 Buick, which later came back as the Rover V8. The new range of BMWs ran from 1962 to 1972, first 1500 then 1600 and then the 2000C and 2000CS, which were in turn enlarged with 6 cylinder engines in 1969 with the E9 2800CS , and 3 years later with the larger E12 "5 series".