First built in 1974, the TR7 was aimed at the US, but soon made waves over here

The erudite Steve Cropley, editor-in-chief of Autocar magazine, once recounted to me the saga of his TR7 convertible. The car had many good points - its comfort, steering, driving position and, on later models, its gearbox. But he also recalled its "limp" performance, which he cured (and few people would go this far) by installing a beefy Rover V8 engine.

After giving the car more power, he then realised that its suspension, brakes and differential were too weedy to cope. So he fixed all those, too, and even reinforced the bodywork so that the TR7 wouldn't implode when he put his foot down.

It was a reminder of what an anaemic thing the TR7 was. The first was built in September 1974 to grasp the baton of the popular TR2-6 series, but the 7 abandoned their tradition of raucous hedonism. Monocoque construction (instead of a separate chassis) gave refinement, yet a four-cylinder Dolomite engine and four-speed gearbox were hardly feisty. Flat-capsters scorned the styling, by Harris "Mr Allegro" Mann, and it only came as a coupé.

Many discerning drivers migrated to new-generation performance cars such as the Volkswagen Golf GTi, and British Leyland ended the TR line for good in 1981; for a company stricken with every conceivable ill, replacing the TR7 was as high a priority as free fruit for each employee. Even the patient Steve Cropley got fed up and sold his pet project, at a thumping loss.

Despite all this, one does need to remember the TR7 in context. It was developed in the early 1970s primarily as an export car for the US, where its crude predecessor, the TR6, seemed doomed. Car-makers believed that legislators would outlaw soft-top cars on the grounds of poor passenger protection. Although such laws never materialised, a whole generation of much-loved classic models was never properly replaced - including soft-top Cadillacs and Ford Mustangs.

Similarly, the Triumph management decided to make the seventh TR only as a hard-top coupé. Pop-up headlights were part of a shovel-fronted body style whose lines rose towards the rear to form a wedge shape, and spongy bumpers that rebounded into shape after a 5mph impact were incorporated to satisfy more US safety requirements. In place of the TR6's raw 150bhp power from its rowdy, smog-producing, 2.5-litre straight six, the TR7 received a four-cylinder, 2-litre motor giving a meek 105bhp.

The frustrated he-men of Britain's motoring press deplored the TR7, but it was an eye-catcher at a time when the creaking Triumph Spitfire and MGB were still prevalent. TV producers clamoured to get the car into their shows. Joanna Lumley's Purdey drove one in The New Avengers; Martin Shaw peeled the rubber off his on roundabouts in The Professionals; and Rudolf Nureyev ordered one.

Even its detractors admitted that it was civilised and pleasant, with a good cabin - aside from some ludicrous upholstery options in bright green or red tartan - and a capacious boot.

But open cars always seem faster than they are; without a canvas roof to throw back and let the fresh air rush in, the TR7 always seemed prosaic. Stuck inside a TR7, the driver became dolefully aware of the tardy 0-60mph time of just under 10sec, and the 110mph top speed. A TR6, while little faster or more accelerative, felt like a bundle of laughs by comparison, even if a TR7 was more fleet on winding country roads.

Along with a standard five-speed gearbox, the convertible did, belatedly, arrive in 1979. It certainly had some razzle to it, the sort of machine that might now feature in a Jilly Cooper bonkbuster. Steve Cropley's dream machine also, briefly, came to showroom life, as BL launched its own V8-engined Triumph TR7, named the TR8, in the US; an impressively gutsy car, even if these factory-built cars had the same alarmingly feeble brakes that our intrepid Autocar tinkerer discovered on his own TR7.

It was two steps forward and one back. The TR7 had originally been built at a particularly militant factory at Speke in Liverpool; indeed, the workers there were on strike the very day, 1 November 1977, when Michael Edwardes arrived to sort BL out. After he axed the plant, the car's production line headed south to Canley, Coventry, and when that industrial edifice closed, too, the TR7 roadshow decamped again, this time to Solihull. Consequently, there were constantly inexperienced, insecure workers nailing the cars together, and the customers (the first TR7 went on British sale at £2,999 in 1975) bore the brunt of this as gremlins soon emerged.

In six turmoil-filled years, 112,368 TR7s and 2,715 TR8s were produced. Not bad... except that it was continually outsold by the decrepit MGB virtually to the end. When they filled the skips at Solihull with the TR7 production tools, in October 1981, however, the Triumph sports- car tradition was junked simultaneously.

Nowadays, obviously, the car is yet another diverting novelty in the classic-car arena, generally driven not by groovily attired 1970s retro freaks but by bearded diehards with spanners in the boot. You could buy a stunning example of the coupé for £4,000, about £1,500 more for a convertible, while a usable coupé can be had for a grand if you trawl the classified ad detritus of your local paper.

But take a note out of Steve's book; if it's thrills you want, a TR7 might not be the best place to start.

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