Improved PerformanceBy 1955, some owners were demanding more performance from the Austin-Healey 100. Donald Healey had already created the limited-production 100S racing version of the car, with a four-port aluminum alloy cylinder head giving 140 bhp. But only 55 of these cars were built, and they really were thinly disguised racing cars. A more practical solution was the Austin-Healey 100M. Regular production cars were removed from the assembly line and hotted up with the M package, although dealers could also order the parts as a kit and do the treatment.
The package was based upon the modifications from the 1953 Le Mans race and included larger 1-3/4-in. SU carburetors on an enlarged manifold, the Le Mans camshaft, a distributor with a different advance curve and higher compression pistons. A cold-air box and ducting supplied the carburetors with fresh air. A larger diameter front anti-roll bar and stiffer shocks took care of the suspension, while the hood was given a series of louvers and was restrained with a leather strap, just like those on the Le Mans cars. All factory-modified 100M cars were given a two-tone paint scheme as standard. The engine cranked out about 110 bhp, and the car was capable of 0 to 60 mph in about 10.0 sec. and a top speed of 118 mph with the windshield lowered.
About 1,200 cars were modified to 100M level by the factory, and many were also modified by dealers or owners using the 100M kit.
Six CylindersSix-cylinder engines were first tried in the Austin-Healey in 1955, and it is the six-cylinder cars that most people think of today as the definitive big Healey. The 100 Six began production in September 1956 and through several iterations finally went out of production as the Austin-Healey 3000 BJ8 at the end of 1967. Available with two and four seats, and eventually with wind-up windows, a refined convertible top and a luxurious interior, the six-cylinder Austin-Healey models were comfortable and fast grand touring cars that could also be very effective competition machines.
The big Healey (called that to distinguish it from the diminutive Austin-Healey Sprite that was introduced in 1958) really found its form in international rallies. In its final competition form, it was a fearsome beast with upwards of 200 bhp and was driven by some of the best and bravest in the business. The six-cylinder road cars were much more refined, although perhaps less a sports car than the early four-cylinder Austin-Healey Hundred models. But to Americans who had been brought up on large sedans and lazy V8s, driving any Austin-Healey was an experience that was pure excitement. Before the car finally ended production in 1967, nearly 74,000 big Healeys had been built. Today the six-cylinder models are perfectly capable of keeping up with modern traffic and are more popular among collectors than the four-cylinder cars.
Driving TimeSo what's it like to drive an Austin-Healey 100? In a word, it's fantastic, especially if the car in question is a higher performance 100M. It's all very vintage feeling. The seats are low-back buckets, a large tachometer and speedometer dominate the metal dash, and the starter is engaged with a pushbutton on the dash. As the car idles, the flexible chassis shudders slightly, like a nervous racehorse ready to take to the track. The exhaust burbles a muted tone that is unique to four-cylinder Austin-Healeys. The view over that long curving hood is enticing, and it's easy to imagine the tree-lined back road is the Mulsanne straight at Le Mans. With so much displacement, the 2.6-liter four cylinder provides plenty of torque, and the car moves away effortlessly when the light-feeling clutch is disengaged. The gearbox, while not as precise as that in a modern car, has a wonderful, direct feel to it, and you are always aware that you are moving big metal gears through hot oil while you shift.