MGC Background and Specification

Background to the MGC

The MGC was firmly based on the MGB, and was intended as a replacement for the Austin-Healey 3000 which, by the time the MGC was announced in 1967, had had its day. It was powered by an in-line, six-cylinder, pushrod, OHV engine of 2912cc capacity that was capable of developing 150bhp. The bodyshell was essentially a basic MGB unit.

Both roadster and GT versions of the MGC were available, but the car was not received well by the press, despite the fact that it had a top speed approaching 120mph. They complained that its handling and acceleration were poor, and that it looked too much like the MGB. It was, however, a very good, long-legged touring car.

The MGC should have been one of the best-selling sports cars of all time, because in concept it offered a much improved performance over the MGB on which it was based, at a similarly low price. But sadly the MGC was to be very short lived, for in 1969 it was dropped from the MG range. No doubt that its poor reception by the press had affected sales, and by then MG had come within the British Leyland group, where Triumph products were looked upon with favour - and the MGC could have made life difficult for the Triumph TR6.

Engine and Suspension Differences

By the time the MGC was introduced, Abingdon had lost control of engine design to other sectors of the vast empire which was British Leyland. The MGC's new six-cylinder in-line engine turned out to be around 25kg too heavy, and the precious balance of the car - the foundation of every MG's fine handling characteristics - was destroyed. The car meant to replace the Austin-Healey 3000 had lost the Abingdon touch, but its other qualities have ensured that it is still much sought after today.

MG did it's best with the weighty problem of fitting the C-series engine into the MGB bodyshell. The main problem was that they were unable to place the engine as far back in the car as they would have liked to maintain the weight balance of the car, as it had to be able to accommodate the relatively bulky automatic transmission for the American market. Hence, the engine had to sit well forward in the engine space, which made the MGC very nose-heavy.

To accommodate the engine, some changes had to be made to the bodyshell and mechanics of the MGB. From the outside, the most obvious changes were the bulge in the bonnet and the 15 inch road wheels. The bonnet bulge was essential to clear the top of the long tall engine, and the larger radiator which it required.

It was also found necessary that the front crossmember, upon which the suspension and engine were mounted in the MGB, had to be removed to clear the bottom of the engine, in particular the oil sump. This meant revising the front suspension from the original coil spring set-up of the MGB to one which used torsion bars as the springing medium. These ran back longitudinally, to a mounting point below the floor, to transfer the suspension stresses back to the centre of the reinforced bodyshell. The rear suspension was essentially the same as the MGB, but a much stronger rear axle had to be fitted to accommodate the increase in power, and also the spring rates had to be increased both front and rear to accommodate the extra power and weight. There was also a new stronger, all synchromesh transmission for the same reason, and as with the B an optional automatic transmission.

The Demise of the MGC

When the first road test reports on the MGC appeared, MG engineers could not believe that the press had been driving the same cars which they had! The general handling of the car was panned by the press, it was said to suffer from terminal understeer, and to be an unworthy successor to the Austin-Healey, which had by now been discontinued. The press did not like the fact that it was so very similar to the MGB, and felt that it should have been a little more modern in its interior appointments.

However, there are few MGC's which would actually fail to get round a corner - the understeer is not "terminal". Looking at the weight balance of the car (53 : 47), will show that there is obviously a preponderance of weight at the front of the car, but this is less than most saloon cars of that period, and of most pseudo-sports cars.
It is likely that two factors contributed to the contemporary feeling that the car was nose-heavy. Firstly, the car looked like an MGB, and it was expected that everything else would be like the smaller car. Secondly, it is likely that the press were lulled into a false sense of security by the quiet and smooth running of the car, which was at a far better level than any other sports car to that date. These two points combined, and drivers found that they were travelling faster than they thought they were, with the result that the next corner would not have been "on" in any car!

The poor reception the press gave the MGC undoubtedly shortened its production life. Its introduction was soon followed by the formation of the British Leyland group, and the fact that the MGC and Triumph TR6 were competing for the same sector of the sports car market. There was considerable feeling against anything emanating from the old BMC part of the group at the time, and it took only a month or so for the board to make a decision on the future of the model. The MGC was dropped from the range in 1969, while the TR6 continued until 1976.

The  MGC Today

Many fine examples of the GT and roadster versions are now owned by enthusiasts in Australia. These have been imported over the years from the UK or the USA and converted to right hand drive.

Today they are a much sought after model in either roadster or GT versions for those that are looking for a good touring car or as the base for a competition car.

Many of the initial criticisms of the car have been sorted out over the years with the application of modern technology. The fitting of modern wider (at least 185/65 15) tyres run at the correct pressures and 5lb higher pressure in the front tyres has improved the original handling concerns. Some sympathetic attention to the suspension will further enhance the handling and there are a number of MG specialists that can help further develop the engine's performance and handling if required.

MGC Production Specifications

Production Period


Fuel consumption and Speed

0-60 10 secs
Overal fuel consumption 19.3 mpg
Top Speed 118-120mph (~193kph)


Unit Construction body, welded steel constuction, all suspension mounts frame.

Wheelbase: 7ft 7in
Track Front: 4ft 1.00in
Rear: 4 ft 1.25in


Cam Gears rack & pinion system.

Turning circle: 34ft
Grade of oil: SAE 90


Disc front, drum rear.

Disk size front: 11.06in
Drum size rear: 10in
Method of operation: Hydraulic, vacuum servo assisted as standard. Dual system for USA. Girling manufacture. Cable operated parking brake.


Either steel disc bolt-on, or Rudge type wire spoked.

Rim size: 5J * 15
Tyre Size: 165 * 15
Tyre pressure: 21psi front, 24 psi rear


6 cylinder in line, pushrod ohv.

Bore: 83.36mm
Stroke: 78.90mm
Cubic capacity: 2912cc
Power output: 150bhp @ 5250rpm
Oil pressure: Approx. 60psi. 20psi at idle
Grade of oil: SAE 20/50
Sump Capacity: 7 quarts (without filter), 8 with.

Ignition Timing

20 deg @ 1000rpm

Distributor points gap: 0.015in
Sparking plugs: N9YC
Gap: 0.025in

Carburetter Type

Twin SU HS6

Jet size, main: 0.100
Needle recommendation: ST. (Spring loaded type: BAD)


Borg & Beck Single dry plate

Material: Ferodo
Number of springs: Single Diaphragm


Four speed manual, synchromesh on all gears. Overdrive optional extra. Borg Warner 35 automatic gearbox was also available.

Ratios: Manual, Overdrive, B-W Auto

Overdrive (where fitted): 0.820
Top: 1.000, 1.000, 1.00-2.2
Third o/d (where fitted): 1.072
Third: 1.307, 1.307
Second: 2.058, 2.058, 1.45-3.1
First: 2.98, 2.98, 2.39-5.5
Reverse: 2.679, 2.679, 2.09-4.598

Grade of oil: XL 20/50
Capacity: 5.25 pints or 6 pints with overdrive, automatic gearbox capacity including oil cooler is 14.5 pints which includes 5 pints in the torque converter

Propellor Shaft

Open shaft, needle roller u/j at each end.

Final Drive

Live axle, hypoid bevel gears.

Ratio: Manual 3.07, o/d & auto 3.307
Later cars: Man 3.307, o/d 3.70
MPH/1000rpm: Manual Top: 24, o/d: 27
Later cars: Top: 22.1, o/d: 24, Auto: 22
Grade of oil: SAE 90EP
Capacity: 1.5 pints

Cooling System

Pressurised, thermostatic control, pump assisted.

Fuel Tank Capacity

Approx. 12 gallons. Tank located at rear of car under boot floor.

Body Styles

Tourer, GT

Numbers built:

Year Roadsters GTs
1966 9 4
1967 182 38
1968 2596 2491
1969 1757 1925
Total 4544 4458


Date Roadster GT Notes
Nov 66 101 110 Pre-production, only 13 cars built in 1966
Oct 67 115 116 Pilot production
Nov 67 138 - Start of roadster series production
Dec 67 - 638 Start of GT series production
Dec 67 580 754 Highest numbers issued in 19671
Jan 68 146 640 Lowest numbers issued in 19681
Oct 68 4266 - Start of 1969 model roadster
Nov 68 - 4236 Start of 1969 model GT
Dec 68 6032 5884 Highest numbers issued in 1968 1
Jan 69 4793 4467 Lowest numbers issued in 1969 1
Aug 69 9099 9102 End of production

1 Because of the overlap in car numbers it is not possible to say whether cars 146 to 754 were built in 1967 or 1968. Similarly, cars 4467 to 6032 might have been built in either 1968 or 1969.