The Triumph TR4’s main challenge was maintaining the traditions of its predecessor without allowing considerably more comfort to comprise the core appeal of a Triumph sports car. The OHV I-4 engine driving the rear wheels was bored out to 2,139cc – the older 1,991cc remained available - and winding windows replaced Plexiglass. The separate chassis, disc/drum brakes, front coil springs and live rear axle were familiar from earlier models, but the front suspension geometry of the TR3A underwent revision to maintain the ride height of the larger TR4 and the side rails were reinforced. There was also a new bodyshell (designed by Michelotti), steering was now via rack and pinion, as opposed to the previous cam and lever, and there was an all-synchromesh gearbox. The top speed was 105mph.
Sales of the Triumph TR4 commenced in October 1961 in the UK; US customers would not receive imports for another year. TR3A owners were amazed by the comfort of the TR4’s cabin, with dashboard-mounted fresh air vents (a first for a British sports car) and various roof options. The ‘Roadster’ had an entirely removable vinyl hood while the ‘Hard Top’ had a rear window attached to a fixed frame with a detachable metal panel over the main cabin. This looked exceptionally neat, but the roof was too large to be stored in the boot, so Triumph offered a ‘Surrey rop’ with a canvas insert into place of the removable aluminium roof. These last two layouts predated the Porsche 911 Targa by several years. Initial prices were £1,09419s 9d for the soft top and £1,14 0s7d for the hard top. Other extras included overdrive – which boosted the top speed to 110mph, a heater, and wire wheels.
From late 1962 onwards TR4s had Stromberg 175CDs carburettors instead of SU HS6s and the Hard Top came with a steel centre section. Triumph never officially offered a coupe version, but Harrington Coachbuilders made a Dové GTR4 2+2 hardtop, but a price of £1,250 meant that few were sold. In 1963 a TR4 was a class winner at the Sebring 12 Hours race and the Modified Championship at Daytona in 1965. In the UK they served as traffic patrol cars in Manchester and Southend.
Production of the TR4 ceased in January 1965 with the advent of the TR4A.
The Triumph TR4 was powered by either a 1,991cc I-4 OHV or a 2,138cc I-4 OHV engine, although the former was rarely specified. The standard gear change was a 4-speed all-synchro box with optional. Laycock de Normanville overdrive on the top three ratios.
The TR4 blends elegant Italian lines with a rugged practicality. As compared with both the Triumph TR3A and its contemporaries, it is spacious, well planned and the Surrey top exemplifies Triumph’s attention to detail.
Common problems for the TR4 include overheating, rear suspension wishbone bracket failure, and head gasket problems. The chassis is also known to rot, so check around the outriggers, arms underneath the boot and in the area of the rear suspension. Excessive noise from the back end of the car can denote a tired differential. Parts are not as difficult to source as many of the TR4’s contemporaries, apart from the Surrey top.
Triumph took a considerable risk with the TR4 as it was so radically different from previous TRs. Its commercial success was a clear demonstration that motorists on both sides of the Atlantic did not find comfort incompatible with sporting prowess.
Rivals for the TR4 ranged from the MGB and the Sunbeam Alpine Series II/III/IV to the Fiat 1500 Cabriolet and the Nissan Fairlady SP310.