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Austin-Healey 100, 100-Six and 3000 (1953 to 1967)

By Jon Cosson · Last checked 14 October 2026

The Austin-Healey 100, 100-Six and 3000 (1953 to 1967), known as the Big Healeys, are powerful, handsome British sports cars. Chassis and body rust, left-hand drive cars converted to right-hand drive and faked 100M or works cars mean careful checks.

At a glance

Years: 1953 to 1967 (100 BN1 from May 1953, BN2 from August 1955 with factory 100M; 100S built 1955; 100-Six BN4 from 1956 and BN6 from 1958; 3000 Mk I BN7 and BT7 from 1959, Mk II 1961, Mk II convertible BJ7 1962, Mk III BJ8 1964; production ended late 1967)
Body styles: two-seat roadster (BN1, BN2, BN6, BN7); 2+2 roadster (BN4, BT7); 2+2 convertible with wind-up windows and fold-up hood (BJ7, BJ8)
Engines: Austin 2660cc four-cylinder (100); BMC C-series six-cylinder, 2639cc (100-Six) and 2912cc (3000)
Built in: Body and chassis units by Jensen at West Bromwich, England; assembled at Longbridge, Birmingham, until late 1957, then at Abingdon (then in Berkshire, now Oxfordshire); 100S hand-built by the Healey company at Warwick

Why people buy one

Strong, torquey engines, particularly the six-cylinder 3000, and a famous competition record in racing and rallying.
A wide choice, from the open four-cylinder 100 to the more civilised BJ8 with wind-up windows, a wooden dashboard and servo brakes.
Overdrive was widely fitted, making the cars relaxed at motorway speeds.
Mechanical parts and body panels are widely reproduced, and the cars are well understood by specialists.
Strong club support in the UK and abroad, including registers for specific models.

What to weigh up

Rust in the chassis and the steel body is common, and the body tub is welded to the top of the chassis, so structural repairs are complex.
Classics World notes that the vast majority of British sports cars of the era were exported, mostly to the US. Many UK cars are repatriated left-hand drive cars, often converted to right-hand drive, so check what the V5C and history say.
Only 640 100Ms were built at the factory, according to the 100M Registry, but about 500 "Le Mans" kits were also sold and many more cars have been converted since, so a claimed factory 100M needs its chassis number checked.
A claimed works or competition history needs documents, not just period-style details.
Low ground clearance and a low-slung exhaust, a hot cabin and limited rear space in the 2+2s.
The Sprite is a different, much smaller car and has its own profile.

Where they rust

Chassis main rails and their joints with the outriggers.
Outriggers running from the chassis rails out to the sills; weak ones cause sagging and uneven door gaps.
Outer and inner sills under the doors.
Floorpans and footwells.
A-posts and B-posts, including the door hinge mountings.
Front and rear chassis crossmembers, often damaged by trolley jacks.
Bottoms of the steel doors and wings, especially the inside of the lower few inches.
The aluminium bonnet and boot shrouds do not rust, but can suffer electrolytic corrosion where they meet steel.

Mechanical weak spots

Engine: Classics World suggests roughly 50 to 60psi warm at 3,000rpm and 20 to 25psi at idle; under 40psi on the move is a concern, though gauges can be inaccurate. All the engines tend to leak oil, and blue smoke means worn bores or valve stems.
Carburettors: the triple SU setup of the 1961 to 1962 3000 Mk II (BN7 and BT7) is hard to keep in tune; the Mk I, the BJ7 and the Mk III use two SUs.
Gearbox: the BN1 has a three-speed gearbox with overdrive on second and top, while later cars have four speeds. First gear has no synchromesh, and overdrive should engage and disengage with no more than a gentle bump.
Steering is worm and peg, and Classics World considers 1 to 2cm of play at the rim acceptable.
Wire wheels: clunks on and off the throttle suggest worn hub splines.
Brakes: drums on early cars and front discs on the 3000 from 1959; servo assistance was optional and later standard. Retrofitted discs and servos are common, so check what the car actually has.
Suspension: check the ride height is even and the rear does not sit unusually high or low, which suggests tired or new springs.

At a Mathewsons viewing

Find the chassis number plate on the front bulkhead and check it, and the engine number, against the V5C; the body number is on a separate plate nearby and the two are sometimes confused. Ask for a British Motor Industry Heritage Trust certificate confirming the original specification and market (these cover Longbridge and Abingdon-built cars, not the 100S).
Ask whether the car was originally left-hand drive and has been converted, and ask for the conversion and import paperwork.
On a claimed 100M, 100S or ex-works car, ask the relevant register or club to confirm the chassis number before you bid.
With a torch, look underneath at the chassis rails, outriggers, crossmembers and sills for rot, fresh welding or thick underseal, and compare the door gaps on both sides.
Lift the carpets and check the floors and footwells, and if staff start the car, watch the oil pressure gauge and look for smoke; do not assume it will be started.

Parts, specialists and clubs

Mechanical parts, chassis sections, body panels and trim are widely reproduced, so even a poor car can be restored, though bodywork on these cars is skilled and expensive work. Original or correct parts for early 100s and the 100S are harder to find. The Austin-Healey Club in the UK has model registers and technical advice, and the 100M Registry tracks factory 100M chassis numbers.

Seen on Bangers & Cash

No appearances found in our car finder.

Sources

'Big Healey' buyer's guide (Classics World), 17 September 2024
Austin-Healey 3000 buyers guide: Big Healey, big decisions (Classic Car Hub), 13 June 2026
Austin-Healey 3000: Buy one now? (Classic Motorsports), July 2024 (posted online 21 September 2026)
1961 Austin-Healey 3000 originally delivered to Texas (Classics World), 19 July 2023
History (100M Registry), accessed 14 October 2026
Austin-Healey 100 (Wikipedia), accessed 14 October 2026
Austin-Healey 100-6 (Wikipedia), accessed 14 October 2026

An independent guide from Thornton-le-Dale. Not connected with Mathewsons or the programme.