The TR3 refined Triumph’s basic formula with the TR2 – a robustly attractive rear-wheel-drive 2-litre open two-seater. The ladder type chassis, worm-and-peg steering, front coil springs and rear live axle with leaf springs remained the same, but there was now a proper radiator grille and a more powerful 2-litre engine. The TR2’s 1 1/2-inch SUs were replaced with 3/4-inch SU H6 carburettors, resulting in a power boost from 90bhp to 95bhp. Top speed was 102mph.
Triumph commenced production of the TR3 on 11th October 1955 and price was £950. As with the TR2, overdrive was an extra and there was an extensive list of accessories for both competition and road use. Overdrive remained a very popular option – it raised the TR3’s top speed to over 105mph - and an ‘occasional rear seat’ theoretically gave the Triumph accommodation for a trio of very close friends. The hood could be augmented by a bolt-on steel hard top. The TR3 could also be equipped with a ‘Grand Touring’ conversion kit; sliding side screens and exterior door handles and locks.
Girling front disc brakes were standardised from late 1956 onwards – a first for a British production car – and enthusiastic motorists were offered a ‘high port’ cylinder head which raised the power to 100bhp and the maximum speed to 110mph. During the late 1950s the TR3 was Standard-Triumph’s rally car par excellence.
In September 1957 the TR3 was replaced by the TR3A (although it was never badged as such). There was now a full-width radiator grille, extremal door locks and handles as standard, amber rear indicators and Plexiglass side screens. The windshield mountings were altered in 1959.
The TR4 succeeded the TR3A in October 1961, but Triumph’s US dealers were concerned that the new model would not appeal to their customers. As 90% of TRs were sold in the States, it was decided to fit surplus TR3A bodyshells with the TR4’s 2.2-litre engine and all-synchromesh gearbox. Triumph began to make the export-only ‘TR3B’ in March 1962, six months after TR3A production had formally ceased. The last Bs were built in October of that year.
The Triumph TR3 and TR3A’s engine was a 2,088ccs I-4 OHV unit while the TR3B had a 2,138cc power plant. The first two had synchromesh on the top three gears while the B had an all-synchro box. Laycock de Normanville overdrive was a very common fitting.
Many Triumph TR devotees say that the TR3 is their favourite of the breed, with its combination of the TR2’s profile with extra power and the front disc brakes. A few examples of the TR3B have returned to the UK and some motorists will find the larger engine more enjoyable.
The challenges of Triumph TR3 ownership are much the same as on the TR2; chassis damage thanks to over-enthusiastic driving over the decades and corrosion. Check around the chassis outriggers, the floors of the spare wheel compartment and boot and front suspension trunnions. Engines should be investigated for water in oil and big end problems. Parts for the TR3A are believed to be easier to source than for the TR3.
The TR3 consolidated the success of its predecessor and made the Triumph marque famous around the world. And although even the youngest example is now more than five decades old, they are cars that demand to be regularly driven.
Competitors for Triumph’s TR3 and TR3A included the MGA, the Austin-Healey 100 BN2, the Sunbeam Alpine Series 1, the Morgan Plus 4, the Mercedes-Benz 190SL, and even the Porsche 356.