Healey 100M

We would be familiar with the marketing ploy of adding a badge, or perhaps an extra carburettor or a stripe, special paint and a slightly different level of interior trim. It’s the same car, but different and draws would-be customers on to the showroom floor to part with their shekels for something a little different from the ordinary model. A car that is special.

Performance and speed models have been with us for decades and the Austin-Healey marque was not immune from such activities. Now, sixty years or so later, these comparatively rare Austin-Healey models are highly sought after and command high purchase prices.

The Austin-Healey 100M, for example, is so popular that of the 640 known to have been constructed there would be at least 1,267 left.

In the Beginning

We have to go back to when the Healey 100 became the Austin-Healey 100 at the October 1952 Earl’s Court Motor Show. Part of the agreement for Austin to take on the manufacturing of the new car was that the Donald Healey Motor Company (DHMC) would be provided with a healthy budget to promote the new marque in competition events.

The first twenty Austin-Healeys were assembled entirely at the small DHMC factory at Warwick, England and of these three were taken aside and specially prepared for the 1953 Le Mans 24-Hour race: held over 13-14 June. Two cars actually ran in the race, crossing the line in 12th and 14th places overall.

Production of the Austin-Healey 100 commenced in May 1953, with the very first car leaving the Longbridge line on 20 June 1953 – a week after Le Mans.

The first model Austin-Healey 100, known as the BN1 of which 10,010 were made, was fitted with a four-speed gearbox from the Austin A90 Atlantic. However, in Austin-Healey guise the first gear was blanked off, resulting in three forward gears and a Laycock de Normanville electrically operated overdrive (for second and third gears) was fitted.

Recognizing that the weak link in the car was the gearbox, in August 1955 BMC released the BN2 model that included a number of changes and in particular a true four-speed gearbox (from the six-cylinder Austin A90 Westminster). There were also numerous other minor changes.

While highly sought after today, the BN2 was seen very much by BMC as a stop-gap measure until the first of the six-cylinder cars was released in May 1956. Between August and December 1955 a total of 4,604 BN2s were made.

Le Mans Kits

Following on from the success at Le Mans in 1953 the DHMC, in conjunction with Austin, developed a special tuning kit for the 100: what is now known as a Le Mans kit. To announce the kit a sixteen-page booklet was produced titled Austin-Healey 100 (Model BN1) – Special Equipment and Tuning Instructions.

On page 3 of the booklet were the words “This kit was fitted to the Austin-Healey cars that completed the Le Mans 24 hour race in 1953.” If fitted correctly the engine output of your Austin-Healey 100 rose from a standard 90 to a claimed 110bhp.

The kit included such components as valve springs, 1¾” SU carburettors, high lift camshaft, steel head gasket and leather bonnet strap. Other components mentioned specifically for racing included varied differential ratios, alternative ratio overdrives, harder shocks and springs, heavier anti-roll bars, Alfin brake drums, aero screens and larger fuel tanks.

The kits were available worldwide from any BMC agent that sold Austin-Healeys, where fitting could be arranged, or owners could purchase a kit and fit it themselves.

Of course, the kits were available at the DHMC, where many UK owners had them fitted to their cars either when they bought them new or at a later stage.

While these kits first appeared in 1954, they continued to be available right through until well after the four-cylinder cars were no longer in production. In fact, there is evidence that some BMC dealers still had kits on their shelves through to the mid-1960s.

Such engine modifications continue to be popular today, with a number of Austin-Healey specialists offering tuning parts for the 100, along with many others. However, to fit out an Austin-Healey 100 today would cost a few dollars more than in the mid-1950s, when the Australian cost of the kit was £132 + tax to buy and fit DIY.

Actually if you had an Austin-Healey in the UK, it was possible to have it modified by the DHMC themselves to those 1953 Le Mans specifications as early as the autumn of 1953.

The 100M

There is some confusion around the 100M moniker and what makes for a “genuine” car.

For the outlaying of a not unsubstantial sum, it was possible to acquire a genuine DHMC designed Le Mans kit from as early as 1954. Today, these cars are mistakenly known as an Austin-Healey 100 Le Mans, referring to both BN1 and BN2 models: a title that was never used in period.

These cars are not what we now know as the Austin-Healey 100M.

After the introduction of the BN2 model, in August 1955, a distinct new model was shown at the October 1955 London Motor Show. Known as the Austin-Healey 100M, not only was it fitted with the Le Mans kit, but also high compression pistons, stiffer roll-bar, louvered bonnet and leather strap. This car was raced soon afterwards at the Nassau Speed Week, in the Bahamas, before being driven across the US to California.

The big difference between the 100M and those cars fitted with the Le Mans kit, either when new or afterwards, was that the 100M actually came from the factory complete, albeit by following a rather tortuous build process.

If you would like to read the rest of this story, grab your copy of the magazine today from your local newsagent, buy a digital copy through our digital sales, or subscribe today.

The BMC Experience Issue 9. Apr-Jun 2014 Magazine


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