The Triumph TR4A was built between 1965 and 1968 by the Triumph Motor Company in the United Kingdom. 1974 Triumph GT6 Coupé The Triumph Motor Company had its origins in 1885 when Siegfried Bettmann and Moritz Schulte started producing Triumph bicycles at Coventry, England, United Kingdom of Great Britain and Ireland. ...

The TR4A was an evolution of the TR4, updated with a new chassis. It was hoped the new, but more complex independent rear suspension would address the buying publics' desire for more comfortable riding sports cars. This version has an "IRS" badge on the rear. It's estimated 75% of TR4A were built with IRS. 1962 Triumph TR4 The Triumph TR4 was a sports car built in the United Kingdom by the Standard Triumph Motor Company and introduced in 1961. ... An Independent Suspension is an automobile suspension system that allows the wheels on an axle to move independent of each other. ...

But, Triumph was again hedging their bets. In response to dealer requests, approximately 25% of TR4A were produced with a solid rear axle (also called a live axle), similar to the earlier TR4. This might also have been a nod to the popularity of the cars as production racers, since the solid axle design was much more easily and less expensively prepared for competition work.

The new suspension did eventually prove itself with the buying public and in racing, with three TR4A IRS posting a team win and finishing 1st, 2nd and 3rd in class at the Sebring 12 Hour race of 1966.

In 1965, the TR4A IRS sold in the United Kingdom for approximately £968, with wire wheels being another £36, overdrive £51, heater £13 and seat belts £4 each.

In 1968 the TR4A was replaced by the 6-cylinder TR250 (U.S. model with twin carburetors) and TR5 (UK/European model with P.I. or petrol injection), both of which continued to to use the same body design.

The TR6 was in development, but not ready for production. It would sport a new Karmann body design, but interestingly still shared the TR5/250 drivetrain, TR4A/5/250 chassis, doors, windscreen and more. 1972 Triumph TR6 The Triumph TR6 (1969–1976) was the best-selling Triumph in history when production ended in 1976. ... Wilhelm Karmann GmbH in Osnabrück, Germany is an independent company in the motor vehicle industry. ...

Specification

Engine: 2,138 cc, 4 cylinder, 86 mm bore, 92 mm stroke, 9:1 compression ratio, 104 bhp (76 kW)

Wheelbase: 2,240 mm (7 ft 4 in)

Length: 3,835 mm (12 ft 7 in)

Width: 1,460 mm (4 ft 9.5 in)

Height: 1,170 mm (3 ft 10 in)

Turning circle: 10.1 m (33 ft)

Capacities:

Fuel tank: 53.4 L (11.75 imp gal)

Engine sump: 6.2 L (11 imp pt)

Gearbox: 0.85 L (1.5 imp pt)

Acceleration in top:

30 to 50 mph: 8 s

40 to 60 mph: 8 s

60 to 80 mph: 11 s