MGB roadster and GT (1962 to 1980)

Why people buy one

• Parts supply is close to complete, from mechanical parts and trim to every body panel and complete new bodyshells.
• Simple, robust B-series engine and conventional rear-drive running gear that most classic mechanics know well.
• Strong club support, with a dedicated MGB Register within the MG Car Club and a large MG Owners' Club.
• The GT adds a usable hatchback and a little rear space, making it a practical everyday classic.
• Later black-bumper cars, revised from 1976 for the 1977 model year, gained a rear anti-roll bar, a thicker front bar and a revised dashboard, and unmodified late cars are becoming scarce.

What to weigh up

• Rust is the main enemy, and Classic & Sports Car warns that repairs are often poorly done. A car can look solid while hiding corrosion underneath.
• Black-bumper cars sit higher to meet US rules and lean more in corners, especially early ones built before the 1976 suspension revisions.
• Many black-bumper cars have been converted to chrome-bumper appearance, and many standard cars have been lowered or modified, so check what the V5C describes.
• Reshelled cars are common. Classic & Sports Car notes early Heritage shells were as rust-prone as the originals, and shells have been galvanised only since the early 1990s.
• The factory GT V8 (about 2,591 built) was never offered as a roadster, so any open V8 is a conversion, and V8 badges on their own prove nothing.
• The MGC is a separate six-cylinder car and is not covered here.

Where they rust

• Outer sills, inner sills and the castle rail beneath them; bubbling where the wings meet the sill suggests the inner sill is poor.
• The ledge at the top rear of the front wheelarch, which traps mud and rots the front wing behind the wheel.
• Front and rear wing top seams.
• The "trumpet" sections at the top of the inner front wings.
• Floorpans and footwells, including the joint with the toe board.
• Door bottoms.
• Rear wheelarches and the joint between the rear arch and wing.
• Rear spring hangers.
• On the GT, the bottom of the windscreen frame, where no repair sections are made.

Mechanical weak spots

• The B-series engine is tough; worn ones show blue smoke on start-up or under acceleration, oil leaks, knocks and low oil pressure (Classic & Sports Car suggests about 15psi at hot idle and 50 to 60psi at speed).
• Some tappet noise is normal; a silent top end may mean over-tight tappets, which can damage the cam followers and camshaft.
• The early three-synchro gearbox can have a weak second gear; the all-synchromesh box from 1967 is tougher. A noise that stops when the clutch is pressed in neutral is the first motion shaft bearing and is common.
• Overdrive is usually reliable; faults are normally in the solenoid or switch wiring, and later cars with the switch on the gear lever can suffer broken wires.
• Kingpins wear early unless greased every 3,000 miles, and the lever-arm dampers can leak or wear; also check the suspension bushes.
• On the GT V8, the gearbox input gears are the known weak point, so listen for gear noise if the car is run; neglected oil changes harm the hydraulic tappets.

At a Mathewsons viewing

• Check the chassis number plate under the bonnet and the engine number against the V5C, and ask whether the car has a British Motor Industry Heritage Trust certificate, which covers MGB production.
• On a reshelled car, ask for paperwork for the new shell; on a claimed GT V8, ask the MG Car Club V8 Register to confirm the chassis number before bidding.
• Get down with a torch and look at the sills, castle rails and rear spring hangers, and feel up inside the front wheelarch for the mud ledge behind the wheel.
• Lift the carpets and press the floors and footwells for damp, soft metal or fresh underseal, and look for filler at the bottom of the front wings and doors.
• Open the bonnet and check the inner wings and trumpet sections, and if staff start the car, watch for smoke and listen for knocks; do not assume it will be started.

Parts, specialists and clubs

Seen on Bangers & Cash

• MGB GT (Bangers & Cash series 6, episode 13, First shown November 2022)
• MGB GT (Bangers & Cash series 8, episode 6, First shown September 2023)
• MGB Roadster (Bangers & Cash series 9, episode 8, First shown April 2024)
• Orange MGB GT (Bangers & Cash series 11, episode 5, First shown February 2025)
• MGB (Restoring Classics series 1, episode 5, First shown August 2022 on Yesterday)

Sources

• Buying guide: MGB roadster and GT 1962 to 1980 (Hagerty UK), 22 January 2021
• Buyer's guide: MGB roadster (Classic & Sports Car), 3 February 2023
• MGB roadster rubber bumper buyer's guide (Classics World), 25 September 2017
• Visit British Motor Heritage (MG Car Club), September 2020
• Rubber-Bumper MGB: A Sensible Choice (Moss Motoring), 5 April 2009
• Classic Choice: MGB GT V8 (Thoroughbred and Classic Cars, via British V8), December 1982 (republished July 2009)
• MG B Register (MG Car Club Sydney), accessed 14 October 2026
• Heritage Certificates from the British Motor Industry Heritage Trust (FBHVC), 9 August 2022