Austin-Healey 100 BN1 (1953–1955) Price Guide

The BN1 is the original Austin-Healey; the car Donald Healey showed at Earls Court in 1952 and Leonard Lord bought on the spot. It is the lightest, purest, and most direct of all the Big Healeys, and the one that established the formula that Donald Healey would refine across the next decade and a half.

The Car

Production began at Longbridge in 1953 with bodies supplied by Jensen of West Bromwich. The 2,660cc four-cylinder engine was derived from the Austin A90, producing 90bhp at 4,000rpm with 150lb ft of torque at a relaxed 2,000rpm. The gearbox was a three-speed unit with overdrive on both second and third. This is an arrangement that seems odd until you drive it, whereupon the overdrive ratios prove well-chosen for relaxed long-distance cruising. Until July 1954, the BN1 used an aluminium bonnet, boot lid, and lighter rear axle, saving 80kg over later cars. The windscreen folds almost flat for open-air motoring at speed. The chassis is a hefty steel ladder frame with the floorpan and bulkhead welded in to create a semi-unitary structure. Front suspension uses coil springs with double wishbones; the rear uses a live axle located by leaf springs and a Panhard rod. Lever-arm dampers all round. 10,688 BN1s were built.

The 100M and 100S

The 100M conversion, available from Donald Healey’s own dealership as kit P280, transformed any BN1 with a new louvred bonnet, leather bonnet strap, revised pistons, camshaft, distributor, twin carburettors, and the famous cold air box, raising output to 110bhp. Around 500 P280 kits were sold for BN1 and BN2 cars combined. The 100S is a different proposition entirely: approximately 50 full competition cars built with alloy bodywork, Dunlop disc brakes all round, and 132bhp in a car 90kg lighter than standard, most finished in white over blue. Any car presented as a 100S demands rigorous expert authentication.

What Goes Wrong

Electrolysis between the aluminium body panels and the steel structure is the BN1-specific concern; check the shroud-to-wing joints carefully. Structural rust attacks the sills and floor in the usual places for a car of this age. The lever-arm dampers need periodic attention. The three-speed gearbox is robust but unusual; synchromesh is not present on all changes and the driver is expected to double-declutch. Brake drums on standard cars are adequate rather than powerful; many owners have fitted disc brake conversions.

Buying

The early aluminium-component BN1s built before July 1954 are the lightest and most sought-after. A car retaining its original aluminium panels commands a premium over later steel-panelled equivalents. The BN2 that followed introduced a more conventional four-speed gearbox and the famous two-tone paint options, more practical but fractionally heavier. The Austin-Healey Club and the dedicated specialist network centred on restorers such as Rawles Motorsport provide the best buying guidance. Join before purchasing anything.