It was initially produced at the Speke, Liverpool, factory,[3][4][5] moving to Canley, Coventry, in 1978 and then finally to the Rover Solihull plant in 1980.

With the United States showing increased concern for automotive safety in the 1970s, legislations were being considered to ban open roof convertibles in said markets due to rollover risks.

[8] As the US statistically represented the most lucrative market for Triumph sports cars, it was decided that the TR7 would avoid these potential risks by only being offered as a fixed roof coupé.

The interior trim was revised in March 1977, with the broadcord seat covers being replaced with red or green "tartan" check inserts with black leather effect vinyl edging.

The convertible also required a smaller fuel filler cap, as the deck area in front of the boot lid was reduced to allow for the stowage of the hood.

These modifications were also applied to the hard top for the 1978 year model (starting after the factory's summer shutdown in 1977),[12] presumably to maintain commonality of parts on the assembly line.

Only a small number of 1978 year model cars, with the smaller filler cap and lights in the door cards, were produced at Speke, due to the industrial action there in 1977–78.

[12] A further trim change during production at Solihull saw the use of a ruched velour in blue or tan on the seats, with matching inserts on the doors.

The prototype for the convertible version of the original Harris Mann design came from Michelotti and the engineering to make it work was done by Triumph.

However, about 400 hard-top (FHC) TR8s were produced at Speke and Canley, as these were needed (possibly with some TR7s converted by BL to TR8 specification) for the Group 4 homologation of the TR7V8 rally car.

Production records at the British Motor Industry Heritage Trust (BMIHT) cover 58 prototype and pre-production cars, all fixedheads, built between February and October 1977.

However, the failure of the TR7 Sprint to go into full series production is also blamed on BL's sales and marketing department because they claimed its performance was not sufficiently different from the TR7, though its top speed and 0–60 mph (97 km/h) time were almost identical to those for the US specification carburetted version of the 3.5 litre 135 bhp (101 kW; 137 PS) Rover V8 powered Triumph TR8.

It was originally scheduled for launch in 1978, however, due to the closure of the Speke factory and concerns about low potential sales, the Lynx was cancelled.

This was based on the TR7, with a wheelbase stretched by 5 inches (130 mm), with either an O-Series or Rover V8 engine, and both drophead and fastback body styles.

During the latter part of 1979, as an exercise in badge engineering, another MG version of the TR7 was developed under the codename Boxer as a potential replacement for the MGB.

[28] This was possible at the time using the "100-off rule", as John Davenport called it, in the FIA's appendix J to the International Sporting Code 1975.

As well as alternative cylinder heads with different numbers of cams and valves, this list of optional equipment also included many other engine, suspension, and transmission components, and so covered the use of the 4-speed, close-ratio gearbox and overdrive from the Triumph Dolomite Sprint (the heavy duty axle from the 5-speed TR7 was initially homologated for group 3 by another, less clear, route, though re-homologated later, presumably on production of 5-speed TR7s).

[41] In 1975, Appendix J listed yet more modifications allowed, with restrictions, to cars for group 4, including pistons, manifolds, carburettors, and suspension, etc., that could be fitted without the FIA needing to recognize or approve them.

However, the BL rally team had to regain approval for the 16-valve head for the 1978 season, and several others such as Lancia, Toyota, Vauxhall, and Ford had similar problems at that time.

[24] The number of cars suitable for "normal sale"[20] required to gain approval of such a modification under the 1976 rules does not appear to be recorded.

This was homologated as a separate model, the TR8, directly into group 4, but because the TR8 had not yet been launched "as a compromise to keep the BL marketing people happy, it was called the TR7V8 instead.

Journalist and historian Graham Robson quotes John Davenport as saying "In those days there was no rigorous FIA inspection system.

This was primarily the result of the poor relations between management and workforce and frequent strikes at the Speke factory near Liverpool.

In its Frankfurt Motor Show preview edition of September 1977, the German magazine Auto, Motor und Sport reported that the engine of a TR7 press car had given up the ghost and "started to boil" while undergoing a maximum speed measurement exercise over a 4 km (2.5 miles) stretch of track as part of a road test.

[43] At the time of the report, the cause of the problem was still unknown; British Leyland technicians had already been investigating the car, without comment, for nineteen days.

A rationalisation plan introduced by incoming BL chairman Michael Edwardes saw the TR7 put on life support by axing the MG MGB as it was felt that the latter was cannibalizing the TR7's sales - however this controversial decision failed to revive the TR7's fortunes when it too was axed in 1981, with the end of car production at Solihull, which was to become exclusively a Land Rover plant.

However, the Acclaim was a licence-built Honda Ballade, built at the Cowley assembly plant and was pitched as a family saloon rather than as a sports car.