1957 Austin-Healey 100-6

The Austin-Healey 100-6 two-seat roadster was produced by the British Motor Corporation, initially at Longbridge and later at Abingdon, and remained in production until 1959 when it was replaced by the 3000. It was introduced in 1956 as a replacement for the four-cylinder Austin-Healey 100 (later known as the 100-4). In comparison to its predecessor, the 100-6 had a 2-inch longer wheelbase, a more streamlined body, a smaller and wider radiator grille, a fixed windscreen, an air scoop on the bonnet, two occasional seats (which later were optional), and a straight-six engine. The BMC-C series 2,639cc engine had been previously installed in the Austin Westimeter, and initially developed 102 horsepower with the help of a twin carburetor setup. With the addition of a revised manifold and cylinder head in 1957, horsepower rose to 117 bhp. A four-speed manual gearbox was standard, with overdrive optional. The front suspension was comprised of coil springs and anti-roll bars while the rear used a rigid axle with semi-elliptic springs and an anti-sway bar. Girling hydraulic drum brakes provided the stopping power.

The weatherproofing features of the 100-6 were superior to its 100-4 sibling with the addition of the aforementioned fixed windshield along with the use of rubber channels in the pillars that worked in conjunction with rubber flanges on the side curtains. Doors now had locking outside handles and the folding top had a larger plastic back window. The interior featured an armrest between the two front seats, a padded dashboard, and an adjustable steering column. Although it had a fairly large trunk, most of the space was occupied by the car's battery and the spare tire. A little extra room was achieved by relocating the gas filler nozzle from inside to the trunk, to the rear deck.

Special competition versions were built and dispatched to the Bonneville Salt Flats during the summer of 1956 in hopes of generating publicity for the upcoming launch. Donald Healey and American driver Carroll Shelby performed the driving duties and at the conclusion of the numerous speed runs, the six-cylinder Healeys broke 28 International and American records.

The 1957 Austin-Healey 100-6 (BN4) Sports Roadster 2+2
The four-cylinder 100 (BN2) rested on a 90-inch wheelbase, and the 100-6 used a 92-inch platform. In the United States, the Austin-Healey 2+2 Sport Roadster had a price tag of approximately $3,200; the four-cylinder BN2 listed at $3,000, and the high-performance 100M (BN2) at $3,275.

The BN2 was equipped with an overhead-valve four-cylinder engine with a 162.2 cubic-inch displacement, two SU H4 carburetors, solid valve lifters, three main bearings, a 7.5:1 compression ratio, and delivered 90 horsepower at 4,00 RPM and 150 lb-ft of torque at 2,000 RPM. The higher compression 100M version delivered 110 hp. The 100-6 (BN4) was powered by an inline 6-cylinder engine with a 161 cubic-inch displacement, two SU H4 carburetors, solid valve lifters, four main bearings, a cast iron block and head, and delivered 102 horsepower at 4,600 RPM and 142 lb-ft of torque at 2,400 RPM.

The transmission was a four-speed manual with floor shift controls; an overdrive was optional. The steering was via a cam and lever, and stopping power was delivered by Girling hydraulic drum brakes. The front suspension employed coil springs and an anti-roll bar, while the rear had a rigid axle, anti-sway bar, and semi-elliptic leaf springs.

The battery and spare tire were mounted in the trunk. The fuel filler nozzle, previously residing in the trunk, was now positioned on the rear deck. The steering column was adjustable, the dash was padded, an armrest resided between the two front seats, and the doors had locking outside handles. The folding top had a large plastic rear window.

Later in production, the four-port engine was joined by a six-port version which boosted output to 117 horsepower. This engine had a new cast-aluminum intake manifold, larger valves and carburetor throats, and the new cylinder head had six individual ports for intake and exhaust. The four-port version used two SU H1 carburetors and the six-port version received two SU H4 carburetors.

The roadster body was joined by a two-seater (BN6) version in 1958. The standard trim level included disc wheels and could be optioned with a tonneau cover or heater. The Deluxe trim level added wire wheels, a telescopic steering column, an overdrive, a tonneau cover, and turn signals.

Production of the Austin-Healey 100-6 lasted from 1956 to 1959, with 14,436 examples built. Next came the Austin-Healey 3000, named for its '3000cc' (3-liter) engine.

by Daniel Vaughan | Aug 2020