This guide has been written to assist people who are looking to purchase an original Mini 1275GT, or are restoring an original 1275GT, and wish to know the original factory specifications of the car. The 1275GT represented a sports offering of the clubman square front Mini, and was sold alongside the higher performing cooper S of of the time. The car is believed to be essentially a replacement of the Mini Cooper. A large number of 1275GT's were built, however, very few survived due to rust issues, and they are considered a very rare car today. The 1275GT was sold in the UK, Europe and New Zealand. Today, cars can be found in most markets due to aftermarket imports.

Of course, the information in this guide can always be added to, and we would sincerely appreciate it if any enthusiasts had further information on these cars, and encourage you to contact us with that information. We hope this guide is helpful to people looking to purchase or restore the cars. If you have found this useful, please show your support by liking our Facebook page (see the button at the top of the website!).

Production Numbers: 110,673 (worldwide)

Period of manufacture: October 1969 – August 1980

This page is only intended to be a guide, and you should always seek advice from professionals when purchasing vehicles which are represented as original or genuine models.

1. Exterior Features - Austin Mini 1275GT

Various differences and unique features are outlined below, which make a good starting point for the identification of a genuine / original car.

  • Decals / stripes came in one of two forms. British cars had a 3 stripe pattern running along the lower sides of the car (see images). New Zealand cars had larger / thicker stripes higher on the sides of the car, which on the rear quarter panel stated 1275GT (see images).
  • Pre July 1974 cars came with 10 inch Rostyle wheels and were fitted with Cooper S 7.5" disc brakes. From July 1974, the 1275GT was fitted with 12 inch wheels and 8.4” disc brakes. There were two choices of 12" wheels from 1974, either the Dunlop Denovo run flats, or the standard steel wheels with Mini 25th Anniversary / 1275LS type hubcaps.
  • "GT" badge LHS front grille, and "Mini 1275GT" badge above numberplate light on rear bootlid.
  • Front bumper under-riders
  • By 1976, the shell had lost the drip rails under the gutters around the roof. All other models prior to 1976 had these extra drip rails (see images).
  • Post 1976 cars had tinted windows as an option.
  • All 1275GT's had the square clubman style front, on what is otherwise a MK2 body (having internal door hinges, larger glass). The 1275GT received a facelift in 1974 with the introduction of the XE2D2 chassis code, incorporating some body minor changes which cannot be externally seen.




2. Interior Features - Austin Mini 1275GT

The following interior features are standard on an original Austin Mini 1275GT. The paint code and interior code section below gives further details on the available interior trim colours and fabrics, however, the images provide a small sample of the most common interior trim.

  • British cars had a 3 spoke steering wheel with “1275 GT” badge in the central cap. New Zealand cars had a 2 spoke / flat spoke wheel
  • Triple instrument guage (redline at 6,000rpm).
  • 1970/71 GT’s had a hole in the middle of the back seat. This was consistent to all early mini clubman’s of these years. Later models did not have this hole, and it provides one extra way of determining a car's age.
  • The GT also had boot board supports similar to the Cooper S, which were spot welded in. See  image we have showing both these (only the GT has the boot board support brackets, which are not present on the standard Mini).
  • Pre 1974 cars have rear companion boxes covered with vinyl which matched the seat fabric. This was not usually the case on post 1974 cars.
3. Original Paint Colours / Codes - Austin Mini 1275GT

The Austin Mini 1275GT was available in a very large number of colour combinations in terms of both paint colours and interior trim types. The attached colour charts and tables show the colours available forom the factory.

The table provides a full list of all available colours, including the interior trim provided / matched with that particular colour. A small sample of cars showing original colours have also been included in the images.

The large majority of later built GT's appear to be fitted with the "deckchair" style cloth seat fabric, as shown in the images, formally known as "Beige Stripe".


The correct chassis number for a 1275GT will depend on the year of the car. The chassis number prefixes are divided into two year ranges, as outlined below. The correct associated "Commission Number" is also provided.

The chassis number on a 1275GT will appear in two locations. Firstly, it is printed on the aluminium ID tag, and secondly, it is stamped into a rectangular piece of sheet metal, welded to the front bonnet slam/crossmember panel. Images of both locations have been provided.


1. 1969 - 1974 1275GT Chassis Number = X-AD2-XXX-A


  • X = Non significant / just a filler and has no meaning
  • A = Engine type (A = A Series)
  • D = Body type 2 door saloon (D is for cooper S and 1275GT only)
  • 2 = Clubman
  • XXX = The induividual sequential build number of the car
  • A = Longbridge plant where the car was manufactured.


1969 - 1974 1275GT Commission Number = S20D XXX.

Note, "XXX" is the commission number position which will be different on each car. This is a Sequential number starting at 101 for each car type.





2. 1974 – 1981 1275GT Chassis Number = X-E2D2-XXXXXX-A

  • X = Non significant / just a filler and has no meaning
  • E = Engine type (E = 1275)
  • 2D = 1275 GT
  • 2 = Clubman
  • XXXXXX =  The induividual sequential build number of the car.
  • A = Longbridge plant where the car was manufactured.


Commission Number for a 1974 – 1981 1275GT = S20D 19416A

Note, 19416A represents the starting number for the GT. This is a Sequential number starting at 19416A for the GT, and will be different on each car.






5. Engine Number – Austin Mini 1275GT

The 1275GT came with a variety of engine prefixes, listed below:

  • 12H379 = 1275GT with dynamo, negative earth, electric fuel pump and remote type gearbox
  • 12H380 = 1275GT with alternator, negative earth, electric fuel pump and remote type gearbox
  • 12H389 = 1275GT with dynamo, negative earth, mechanical fuel pump and remote type gearbox
  • 12H390 = 1275GT with alternator, negative earth, mechanical fuel pump and remote gearbox
  • 12H706 = 1275GT with alternator, negative earth, mechanical fuel pump and rod

The engine number is located at the front top of the engine block, just above the alternator, or just below the number 1 spark plug. The number is stamped onto a small rivited aluminium ID tag. See images for further clarification.

If you have one of these numbers as the prefix, then its likely correct. The only way you would know for sure that it is the original engine number is by the log books. Note, a 1979 - 1981 1275GT may in fact have the later model A+ engine block which they started using in the Metro in 1982. Austin started producing the A+ block in 1979 so it managed to slip into a few GT’s according to our research.

6. Mechanical Features - Austin Mini 1275GT

The following items are mechanical characteristics of the 1275GT, with several differences explained for the earlier and later models where relevant:

  • The rod change gearbox mechanism changed to the new one (from the solid cast housing to the exposed rod type) from around January 1973 (See images).
  • The floorpan for a 71/72 shell should be shaped to suit the remote gearbox (the central tunnel had a squarer profile for the rod gear change). In early 73 they changed to the rod change box, and the floorpan for this is slightly different.
  • Early GT’s had the smaller 6.5 gallon petrol tank. From 1974, the larger fuel tank (7.5 gallon) was installed.
  • Pre 1971 1275GT's have hydrolastic suspension. From 1971 onward, the 1275GT changes to dry cone suspension.
  • Very early 1275GT's (1969/70) had the bonnet stay mounted on the left side like MK1 cars. This was changed to the drivers side on later models.
  •  the GT motor was a solid chest block with 9 studs for the cylinder head, as opposed to the Cooper S motor which had removable pushrod covers on the rear of the block and 11 stud head and twin carbs, amongst other differences.
  • The early cars of 1969/70 suffered with a problem when cruising at motorway speeds due to a final drive ratio of 3.65:1, this made the cars very noisy and stressful to drive for long periods at 70mph and 1971 model cars changed to the 3.44:1 ratio. This cured the problem abut came with a slight loss of acceleration.
  • The early GT cars were on 10inch Rostyle wheels and were fitted with Cooper S 7.5" disc brakes. From 1974, the 1275GT was fitted with 12” wheels and 8.4” disc brakes.
  • Single 1.5" SU carburetter.