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For a company that built such a wide range of cars in such volumes, Triumph always had an individual streak.
But while both firms made the very best use of in-house components that were shared with more humble machinery, Triumph – to a fault, you could say – always went about it in a slightly different way.
In terms of the Spitfire and GT6 bloodline, much of that was due to the layout of the Herald saloon, which had been launched in 1959.
Its use of a separate chassis was old-hat even then, and its swing-axle rear end not ideally suited to the sports cars that were to follow.
Even so, unsung engineer Harry Webster was convinced that a two-seater based on that platform would be an effective rival to the likes of the Austin-Healey Sprite and forthcoming Midget, and he had Giovanni Michelotti create a prototype, which was codenamed ‘Bomb’.
Sadly, the project took a back seat as Triumph plunged into one of its periodic financial crises, only to be bailed out by Leyland in 1961.
The Bomb was then turned into the Spitfire in double-quick time for a ’62 launch, Webster’s fertile mind already looking ahead and hoping to increase its appeal by developing a coupé variant.
Having raised the idea at board level in August 1963, Webster went back to Michelotti and asked him to come up with something that shared as many panels as possible with the Spitfire.
What the Italian produced was stylish, beautifully proportioned and, thanks to its hatchback rear, surprisingly practical.
The original intention had been to simply carry over the four-cylinder engine to create the ‘Spitfire GT’, but the 1147cc unit wasn’t man enough to cope with the coupé’s extra weight.
The obvious answer was to drop in the Vitesse’s 1596cc straight-six but, although this started the process by which the new model was distanced from the Spitfire, it also failed to produce the required levels of performance.
The firm’s history with six-cylinder engines went all the way back to the 1931 Scorpion and its attempts to move upmarket.
Thirty years later, and despite the fact that it could trace its origins to the 803cc ‘four’ that had been designed for the 1953 Standard Eight, it was the adoption of this engine that would serve to give the GT6 much of its undoubted character.
The public would be given a sneak preview of the coupé via the appearance in 1964 of a squadron of hardtop Spitfires at Le Mans.
Contrary to long-held belief – no doubt fostered by Triumph’s own period GT6 adverts: ‘Bred at Le Mans to put you safely ahead!’ – the shape of the racers was derived from the nascent road car, not vice versa.
In fact, their roofs were constructed using a mould that had been taken from Michelotti’s GT6 prototype.
There were other similarities. In ’64, those competition Spitfires used the 3.98:1 final-drive ratio that the non-overdrive GT6 would later adopt, plus the same all-synchromesh gearbox.
Only one of the three cars finished that year (ADU 2B, in 21st position); two out of four did so in ’65, but Triumph cancelled plans to run a Spitfire with a heavily modified GT6 engine at the following year’s 24 Hours.
The new coupé made its debut at the 1966 Earls Court Motor Show.
As dictated by manufacturing practicalities, the floorpans, bulkhead and doors were the same as those on the Spitfire, even if the layout of the luggage area meant that the fuel tank had to be redesigned and moved to the nearside rear wing.
Triumph had done a good job of giving the model a more sophisticated mini-Grand Tourer image, rather than the spartan sports car brief fulfilled by the Spitfire.
Inside, for example, it was positively luxurious, with a full-width walnut dashboard, carpeting throughout and more comfortable seats.
The dials, meanwhile, were arranged ahead of the driver rather than grouped in the centre of the fascia.
The ‘six’ produced 95bhp – exactly the same as the MGB GT, which was perhaps the car’s most natural rival and which had been launched the previous year.
And yet, as a small, affordable, six-cylinder two-seater coupé, the Triumph occupied a niche pretty much all of its own, giving those who couldn’t stretch to a Jaguar E-type a tantalising glimpse into that rarefied world.
Or, as one road-tester put it: ‘A businessman’s express for the less-affluent businessman.’
The motoring press gave the new car a warm welcome. Despite Triumph’s best efforts to distance it from its four-cylinder sibling, there were the inevitable references to the Spitfire – Autocar rather damning that model’s status by stating that the GT6 was ‘essentially a Spitfire sports car’.
Almost everyone recognised its good looks, performance and value for money, but there was the occasional word of warning over the Herald-derived swing-axle rear end.
After its appearance on the saloon – as well as the Spitfire and Vitesse – that was hardly news to the Coventry engineers, and was addressed on the 1968 Mk2.
In an attempt to calm the lift-off oversteer of the earlier car, the updated version used a lower-wishbone set-up with Rotoflex couplings between the halfshafts and the hubs.
The wishbones themselves were reversed, with the double pivot outboard and the single mounting point inboard.
Beneath the bonnet, meanwhile, the ‘six’ gained a redesigned cylinder head and the TR250’s inlet manifold, which added up to a 9bhp increase in power.
Inside, ventilation was improved so that occupants weren’t slowly baked by the heat from the engine, and there was even the option of a spectacularly useless rear ‘seat’.
‘The new GT6 Mk2,’ proclaimed the advertising copywriters. ‘More sting in the engine, more cling in the tail’.
Certainly it was deemed to be much improved but, in the vital American market at least, sales began to slip after reaching their peak in 1968.
Sadly, the Triumph didn’t live up to its own press as ‘The car that sells itself’.
Canley nonetheless gave the model one last hurrah with the Mk3, which was facelifted along similar lines to the Spitfire MkIV and launched alongside it at the 1970 Turin Salon.
There had been a design proposal kicking around that would have given this latest incarnation a completely new nose with pop-up headlamps, but in the end the biggest changes were at the rear.
Stag-style tail-lights gave the car a very different look, while inside there were flush rocker switches in place of the earlier toggles, and the overdrive switch was relocated from the steering column to the gearknob.
It wasn’t enough to save the model; production stopped in ’73 after a final round of revisions that included dropping the Rotoflex rear end – by then, the GT6 was the only model using it – in favour of the Spitfire MkIV’s swing-spring layout.
The combined effect of BL’s bean counters and US emissions regulations meant that the ‘six’ was slowly strangled over its final couple of years – Federal-spec cars were down to 79bhp for 1972 – but Triumph countered by throwing more and more standard kit at its little coupé, including Sundym glass and a brake servo.
For the most part, the GT6 was saved the ignominious end that befell so many of its BL stablemates. Its looks, for example, were still mostly intact as production wound down.
The whole point of the GT6 was that it brought the glamorous world of six-cylinder GTs within reach of the man on the street, offering an ‘edge’ that its mainstream rivals struggled to match.
The styling certainly helped. Compact at the time – and tiny by modern standards – it ticks all of the right boxes: long, curvaceous bonnet, fastback rear, perfect proportions.
Combined with that sonorous engine, it really does make you feel as though you’re in something worth at least five times as much.
The low driving position is suitably rakish, and you get a great view of the front wings and central ‘power bulge’ – necessary to clear the longer engine.
The offset pedals are typical of many of Triumph’s cars, though.
The featured Mk1 and Mk2 both have the standard powerplant, which is smooth, remarkably subdued from within the cabin and, having plenty of torque, responds instantly and eagerly to throttle inputs.
The gearbox feels pleasingly mechanical and the steering is nicely weighted.
A wet, tree-lined road is not the ideal place in which to explore the in extremis handling differences between the two, but Neil Fletcher – the owner of the Mk1 – explains that he’s taken part in track days and covered countless road miles without being dispatched into the scenery.
As with many cars that have a similarly lairy reputation, it would appear that much depends on how careless the driver is.
At everyday speeds, at least, the first incarnation turns in well and doesn’t feel as if it’s going to swap ends.
‘Our’ Mk3 is a slightly different proposition.
In period, the GT6 was ripe for modification, with SAH TriumphTune, for example, offering five stages that could give anything from 120bhp (hot camshaft, reworked head, six-branch manifold, upgraded carbs) upwards. You could even fit Tecalemit fuel injection or triple Webers.
The trend continues today, the fitment of Triumph’s 2.5-litre engine being a very popular conversion.
Andy Carr has done just that, and the transformation is remarkable. Whereas the standard cars are smooth and relatively discreet, this Mk3 is gruff and forceful.
It has loads of grunt, as you would expect, and feels beautifully sorted.
You do wonder whether Canley missed a trick by never giving the car this unit but, as Carr points out, not doing so kept the GT6 away from the TR range in performance terms.
Also, the various other mods required to prevent the increased power overcoming the chassis’ shortcomings would no doubt have made it financially unviable on such a low-volume model.
And besides, the standard car is plenty good enough to inspire a loyal following 50 years after it was first introduced.
It’s easy to live with, the spares market being strong enough that you could almost build a brand-new one.
Easy to work on, too, with that clamshell front end swinging right out of the way, enabling you to get to the engine while sitting comfortably on a front wheel.
Such practicalities are a bonus rather than the be-all and end-all, though.
The fact remains that the simple mix-and-match premise of this car is one that carries an enduring appeal: take basic off-the-shelf components, add a powerful engine that makes all the right noises, and garnish with an attractive, flowing body.
The GT6 still offers something a little bit different, too – an individual choice from one of the most mainstream of marques.
That’s not something you could say about the otherwise capable and handsome MGB GT.
For the money, this is not a mix that you’re going to get elsewhere. Styling-wise, the Opel GT is up there but lacks the appeal of a six-cylinder engine, as does the less pretty but practical – and dynamically far superior – Lotus Elan +2.
Triumph came up with the GT6 during the prolific period following the launch of the Herald, in which the TR4, 2000, Vitesse and 1300 also appeared.
Having been revived by Standard less than two decades earlier, it’s strange to think that the name would once again have disappeared only 11 years after the GT6 went out of production.
Fortunately, the likes of Webster and Michelotti left us quite a legacy.
Images: Tony Baker
Thanks to Southern Triumph Services
Triumph GT6 Mk1
- Sold/number built 1966-’68/15,818
- Construction steel chassis and body panels
- Engine iron-block, alloy-head, ohv 1998cc ‘six’, twin Zenith-Stromberg carbs
- Max power 95bhp @ 5000rpm
- Max torque 117lb ft @ 3000rpm
- Transmission four-speed manual with optional overdrive, driving rear wheels
- Suspension independent, at front by wishbones, coil springs rear transverse leaf spring, swing axles, radius arms; telescopic dampers f/r
- Steering rack and pinion
- Brakes discs/drums
- Length 12ft 1in (3683mm)
- Width 4ft 9in (1448mm)
- Height 3ft 11in (1194mm)
- Weight 1904lb (863kg)
- 0-60mph 10.5 secs
- Top speed 107mph
- Mpg 26
- Price new £985
Mk2 (where different)
- Sold/number built 1968-’70/12,066
- Max power 104bhp
- Suspension rear reverse lower wishbones, Rotoflex couplings
- Price new £1148
Mk3 (where different from above)
- Sold/number built 1970-’73/13,042
- Suspension rear (from Feb 1973) ‘swing spring’ transverse leaf spring and swing axles
- Length 12ft 5in (3785mm)
- Width 4ft 10½in (1486mm)
- Weight 1936lb (878kg)
- 0-60mph 10.1 secs
- Top speed 112mph
- Mpg 28
- Price new £1287