Spitfire 1500 : The Spitfire 1500 engine.

Two years before the end of MkIV production, Triumph had already introduced the 1,493cc engine in MkIV's for the US market, albeit with a single Zenith Stromberg carburettor. Changing the design to conform with US emission regulations had robbed so much of the old engine's power that an increase in swept volume was badly needed.

In December 1974, the 1,493cc engine was also introduced on other markets, in a mildly reworked model called the 'Spitfire 1500'. The engine, which was basically a stroked version of the old 1300cc engine, produced 71bhp and mated to a simpler 'Marina' gearbox, turned the Spitfire into a genuine 100Mph (161km/h) car for the first time. Fuel consumption was no higher than before but the car was much more flexible to drive, thanks to improved torque.

'Houndstooth cloth' upholstery, introduced in 1977. Throughout its production life, many detail changes were made to the 1500. The main visual upgrade happened in 1976, when - in keeping with the fashion of the time - the bright stainless steel windscreen wipers, chromed door handles and door mirrors were replaced with matte black items. In 1977 the old steering column switchgear, which still stemmed from the days of the Triumph Herald, was upgraded to more modern TR7 column stalks. A few months later, the all-vinyl seats were replaced with cloth-vinyl seats.
Apart from minor changes, British Leyland did not invest in the Spitfire. BL originally planned to keep the Spitfire in production until 1982, but in 1980 it was quickly discovered that the old Triumph 1,500cc engine could not possibly meet new Californian emissions regulations. Since around half of Spitfire sales at that time took place in California, this meant that production halved and became uneconomical. Besides, the car was an old design after 18 years in production and could no longer compete with more modern offerings like Fiat's X-1/9 and BL's own TR7.
The last Spitfire 1500, an Inca Yellow specimen with hardtop and overdrive, rolled off the assembly line at Canley in August 1980, bearing commission number TFADW5AT009898. It was never sold and is still in the British Motor Heritage museum at Gaydon today.