Cooper builds his prototype

Cooper builds his prototype

The original Mini-Cooper prototype. (Picture: Ian Nicholls)

John Cooper then set about building a fast Mini, probably YOK 250. The work was overseen by long-time Cooper employee Ginger Devlin and featured many components from the FJ engine and allegedly had three times the power of the standard Mini 850 engine, which would be around 100bhp. By 1961 the FJ engine was a 994cc unit developed by Eddie Maher of Morris engines in Coventry.

John Cooper approached his friend and Mini designer Alec Issigonis with his idea for a hot Mini. Issigonis intially rejected the idea, seeing his baby as a people's car. Undeterred, Cooper took his idea to BMC's managing director George Harriman, who drove Cooper's prototype and then gave the go ahead for production of 1000 cars for homologation purposes. Homologation is the key word. Right from its introduction the Mini 850 had been used in competition, and a Cooper Car Co-entered Mini 850 won the 1960 British saloon car championship. George Harriman offered John Cooper a ฃ2 royalty on each car, to be sold as an Austin or Morris Mini Cooper, and BMC took on the development of the production car under the codename ADO50.

The 1961 Formula Junior MK2 protototype pictured alongside YOK 250. Presumably YOK 250 is also the car Aurelio Lampredi took for his long excursion at Monza in 1959? (Picture: Ian Nicholls)

Former BMC and Ford competition manager Stuart Turner has since commented that if John Cooper had not come up with the idea of a hot Mini, then someone else would have. The Mini was already a successful competition car in the sub-1-litre category and an MG-badged variant would have been on the cards. As it was, the ADO50 was badged Mini Cooper after the reigning Formula 1 world champions. In 1960 the Cooper Car Co dominated Grand Prix racing leaving the likes of Ferrari and BRM trailing in their wake, so the decision was entirely logical.

And so BMC set about developing the production Mini Cooper, using a Mini registered as KEL 236 as development car.The standard 850's 34bhp gave it a top speed of 73mph using a final drive of 3.765 to 1. Morris Engines calculated that to propel a Mini to 85mph would need 55bhp, so company head Eddie Maher developed a 997cc engine with a longer stroke than the existing 848cc unit, yet bizarrely a smaller bore. Quite why BMC didn't use the existing 948cc block as found in other BMC small cars is unknown, but over the next five years BMC were to develop a bewildering range of different capacity A-series engines. To stop the car Lockheed provided 7-inch disc brakes, which as it turned out were not that good!

Since this article was originally written, Simon Wheatcroft of the Mini Cooper Register has provided an alternative view as to the identity of the prototype Mini Cooper. According to Simon, "The development car was not registered as and only bore the registration KEL 236 in the photographic sequence at Goodwood and was actually 126 LWL. 126 LWL was registered on 20th April 1961 as a Morris despite never being seen with a Morris badge, the car was Farina Grey with a Black roof.

"126 LWL was present at the Mini Cooper launch (badged as an Austin) and was subsequently tested by Sports Car Graphic magazine complete with all its non standard parts such as Morris Minor style 100 mph speedometer and unique interior trim."

The Mini Cooper was launched in September 1961 and was acclaimed by the motoring press. The car had a maximum speed of around 85mph and a 0-60mph time of 17 to 18 seconds, not fast today but impressive back in 1961. Most of the hike in engine power came from the camshaft, part number C-AEG567, which was the hottest cam fitted to a production A-series until the arrival of the MG Metro in 1982. Other gains in power were realised with a cylinder head with larger inlet valves and twin 1¼ SU carburettors. Tuning guru David Vizard later tested the BMC twin-carburettor inlet manifold on a flowbench and found it to be an appallingly inefficient design...

What this writer finds interesting about the 997cc Mini Cooper is that it previewed two components that were to be found on the ADO16 Morris 1100 launched eleven months later: the remote gearchange which replaced the 850's magic wand and the 12G202 cylinder head which was standard equipment on the 1098cc engine found in Austin/Morris 1100s. John Cooper's desire for a hot Mini was somewhat compromised by the need to productionise the concept and use standard BMC components. However help was soon at hand in deepest Wiltshire.