Vauxhall introduced the very first Viva – a two-door saloon powered by a 1057cc four-cylinder engine – in 1963. Although the HA Viva’s box-like body wasn’t about to win any beauty contests, under the skin the car featured up-to-date features such as an all-synchro four-speed gearbox, rack-and-pinion steering and independent front suspension, while buyers could even option in front disc brakes. However, with only 33kW on tap the HA Viva, with a top speed of 128km/h, could hardly be considered a performance machine. The next generation Viva would, however, be the first signs of a change in Vauxhall’s traditional conservatism.

The HB Viva’s much trendier ‘coke-bottle’ styling debuted at the 1966 London Motor Show, the new car’s looks having been penned by Leo Pruneau, a Detroit-based GM stylist who reputedly sketched the HB Viva during a lunchtime break as ‘comment’ on a concept for the car drawn up by Vauxhall’s David Jones. With his design infinitely preferable to Jones’, Pruneau was promptly shipped out to Luton in the UK. Subsequently, he would also come up with the similarly styled Victor before being dispatched to Australia to tidy up the Torana – a car that started life as a HB Viva – and would subsequently be responsible for many iconic Holdens, including the original Monaro.

Work in progress – this MkI GT has been re-shelled many times and is currently being restored by Mike John

However, the first indication that Vauxhall were looking at a performance version of the Viva came with the introduction in 1967 of the Brabham Viva. Powered by a modified version of the SL90 Viva’s 1599cc engine, Brabham Viva added a second 150CD Stromberg carburettor, pancake air filters and a lower rear-axle ratio. The result was an increase in power to 51.5kW and a top speed of 143kph – all these modifications were on offer for £37 10s, while extra-cost items were also available. It is believed that around 250 Brabham Vivas were built.

This set the scene for the Pruneau-designed Viva GT, which finally appeared on the motoring scene in March 1968. Powered by the 1975cc four-banger previously seen in the Victor, fitted with twin Stromberg carburettors and mated to a close-ratio gearbox, the Viva GT was capable of beating the ‘imperial ton’ by a few mph.

On the cosmetic side, Vauxhall added in a matt-black bonnet with twin air-scoops, black front grille, GT badges and a sportier looking instrument binnacle.

Inevitably, top British tuners were soon getting stuck into the Viva GT, seeing in it a potential challenger to the contemporary Lotus Cortina. In Bill Blydenstein’s hands the Viva GT was transformed into a performance car easily capable of dealing to the Lotus-modified Ford.

The MkI GT's engine is a 2.3-litre unit decked out with a brace of Webers

From that point, Vauxhall took a few steps backwards to their traditionally more conservative way of thinking and the Mk II version of the GT dispensed with the matt-black items although the car’s overall appearance was smartened up with a set of Rostyle wheels. Although performance was unchanged, on the road the Mk II seems much less lively than the Mk I – the old boy-racer feel of the earlier model having been replaced with something a little more, well, adult.

All HB Vivas would be replaced in 1970 by the HC models, with the Magnum and Firenza leading to performance Vauxhalls such as the distinctive Firenza Droop Snoot, Chevette HS amongst many others.

The importance of the Viva GT cannot be overstated, and all the performance and GT models produced by Vauxhall over the last 50 years in one way or another owe their existence to this classic GT.

To mark the Viva GT’s 50th anniversary, we met up with representative GTs from each of the three years the model was in production – 1968–1970 – plus two racing GTs.

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