1954 Austin-Healey 100-4 BN1

Donald Healey won the Monte Carlo Rally in 1931 driving an Invicta but failed to finish in 1935 after an accident involving a train while driving one of the three Triumph Dolomite straight-eights.

After World War II, Healey began building sports cars using Riley running gear and bodies that included coupes, roadsters, and dropheads. The biggest drawback was the base price which was more than $4,000. In order to compete with other British marques, Mr. Healey realized that cars needed to be built in larger numbers and sold at a lower price. To accomplish this goal, Healey sourced components from the parts bin of the newly-formed BMC (a merger of the Austin and Nuffield/Morris companies), resulting in a prototype which was called the 'Healey Hundred' which he displaced at the 1952 London Motor Show. It used the Austin A90 Atlantic mechanical components and a sleek body designed by Gerry Coker and built by Tickford. The 'Healey Hundred' prototype, finished in Ice Blue, impressed Leonard Lord, the head of BMW, resulting in a deal to build the car in volume at Longbridge.

It was given the designation, the Austin-Healey '100' due to its top-speed capability. It used a frame comprised of three-inch square box-section steel rails that ran the length of the chassis about 17 inches apart, passing below the front low wishbones and beneath the live rear axle. Brackets extending outward from the main rails supported the alloy and steel body. Mounted in the front was the old Austin 90 long-stroke four-cylinder engine displacing 2,660cc, developing 90 bhp at 4,000 RPM, and 144 foot-pounds of torque at 2,000 RPM. The engine was backed by a three-speed gearbox with floor shift controls, with a Laycock de Normanville overdrive on second and third gears. 11-inch drum brakes were placed at all four corners. Damping was by Girling lever arm units all round and the steering was by cam and lever. The graceful, sleek and flowing bodywork was complimented by an adjustable lay-down windscreen.

The first 25 cars were constructed at Healey's own premises in Warwick, the UK before production of the bodyshells was turned over to Jensen. The completed shells were then sent to Longbridge, where the Healeys were assembled alongside the A90.

The early examples, known as the BN1, were powered by the same 2660cc, 90 horsepower engine, and four-speed transmission as the A90, but Austin modified the gearbox so it operated as a three-speed unit with overdrive on the top two ratios. Top speed was achieved at around 106 mph and zero-to-sixty took 11.2 seconds. This was very impressive, especially considering it cost less than $3,000 in the United States.

Between January 1953 and 1955, a total of 10,688 BN1s were built with most being sent overseas. The BN1s were superseded by the BN2.

The 100M derivative was introduced in 1955 and based on that of the 1953 Works Le Mans cars that finished the 24 Hours race in 12th and 14th overall. The 100M models received a larger carburetor fed by a cold air box for increased airflow, 8.1:1 compression pistons, and high-lift camshafts, increasing horsepower to 110bhp at 4500 rpm. The suspension was modified and stiffened and the bonnet received a leather belt, plus louvers for improved cooling. Total factory production of the 100Ms reached 640 units, all of which were based on the BN2 series cars. The components for the 100M were available in kit form for retrofit to either BN1 or BN2 models and could be ordered direct from BMC, allowing cars to be modified by Austin dealers and private owners alike.

by Daniel Vaughan | May 2020