The first potential racing derivative of the GT6 was the stillborn ‘GT6R’, a project of which only three photographs are known to survive—two credited to Graham Robson, and one to David Pearson of Canley Classics.
As Graham Robson details in Works Triumphs In Detail, the project was born from necessity. After the 1965 Le Mans 24 Hours, it became clear that the works racing Spitfires had reached the end of the road. Race speeds had escalated so dramatically in just two years that a homologated Spitfire stood little chance of even qualifying for the 1966 race. If Triumph wished to continue competing, the existing layout required a significant and costly overhaul: a larger, more powerful engine, a revised rear suspension, and perhaps even a unique body style. For a time, the solution was seen in a new prototype, effectively a racing testbed for the GT6. The plan was to fit the 2-litre, six-cylinder engine that the production GT6 was about to inherit.
A single prototype was built by Ray Henderson. Fitted with Weber carburettors, it was rumoured to produce around 170bhp. However, its fate was sealed not by performance, but by politics. Following the controversial disqualification of the winning Minis at the 1966 Monte Carlo Rally, Triumph’s Donald Stokes halted the entire works racing program, and the GT6R prototype was ordered to be broken up.
According to Italian Triumph expert Fabrizio Comi, who built a meticulous replica of the car in 2017, the GT6R’s build was more complex than simply modifying a standard car. “The starting point for the GT6R project,” Comi explains, “was the ADU5B in a Tour de France setup.” This donor car was a unique hybrid, featuring a steel body shell, aluminium doors, the famous ‘Le Mans’ bonnet with its central aluminium panel, and front wings made of fibreglass. Notably, these wings lacked the central bulge that would later characterise the standard GT6’s bonnet.
The heart of the project was the 2-litre, inline six-cylinder engine. The Competition Department had extensive experience tuning this unit for the Triumph 2000s campaigned in rallies, including the Mk1 registered FHP993C. It was from this very car that a proven, reliable 170bhp engine was donated to the GT6R project.
Ray Henderson began by stripping the remains of the Spitfire ADU1B. To accommodate the longer six-cylinder engine under the bonnet and improve weight distribution, the power unit was both lowered and shifted backwards in the chassis. The most extensive modifications, however, were reserved for the rear suspension. Heavily influenced by that of the Lotus Elan it featured wishbones, coilover units, bespoke hub carriers and rubber doughnuts. A stronger TR differential was also fitted.
