TR6 (TR6)

A New Skin on an Old Frame By 1968 the TR4 body Giovanni Michelotti had drawn for Triumph in 1961 was seven years old and had already been carried over, essentially unchanged, to the TR4A, the injected TR5 and the carburetted TR250. British Leyland had neither the money nor the time for a new car, so the job of making the old one look new went to the West German coachbuilder Karmann, and specifically to Gerhard Giesecke, working with input from Triumph's North American sales organisation. What Karmann delivered was a squared-off front and rear clip - new wings, bonnet, boot lid, grille and tail panel - grafted onto an unchanged frame, suspension, drivetrain, doors, screen surround and body tub. It went from clay to production in a little over a year. The result looked like a different decade from the front and was mechanically the TR5 underneath.

Two Cars, One Badge The central fact about the TR6, and the one most often garbled, is that the engine you got depended on where you lived. Home and European cars kept the Lucas mechanical petrol injection of the TR5: a belt-driven metering unit, an electric pump and a system running at 110 psi, rated at 150 bhp at 5,500 rpm with 164 lb-ft. North American cars could not have it, because the Lucas system could not be metered finely enough to meet United States emissions law - an inversion of the usual story in which injection is the compliance technology. Those cars ran twin Zenith-Stromberg constant-depression carburettors and 104 bhp, with California-bound examples reduced further to a single carburettor. The difference was real but smaller in practice than the badges suggested. Road & Track recorded 10.7 seconds to 60 mph and 109 mph in 1969; Motor got 8.5 seconds and 117 mph from an injected car the same year.

The 1973 Re-rating For 1973 the commission prefixes changed from CP and CC to CR and CF, and the injected engine was quoted at 125 bhp rather than 150. Rimmer Bros and Wikipedia attribute the change to a milder camshaft adopted to improve behaviour in traffic; Ate Up With Motor is more specific, saying Rover-Triumph substituted the shorter-duration camshaft from the federalised cars after complaints about rough idling, and gives the new figure as 124 hp. Auto Express attributes the detune to emissions requirements. Hagerty UK argues that the paper drop overstates the real one, because the convention for quoting output changed at the same time. All four cannot be simultaneously correct about cause, and none of them separates the mechanical loss from the arithmetic one. The same year brought a front air dam, revised instruments and horn arrangements, and headrests; overdrive became standard for 1974.

Built for Somebody Else The TR6 was a British sports car built almost entirely for export. Every source consulted agrees that only 8,370 were sold in the United Kingdom. Estimates of United States deliveries run from Hagerty's 76,470 to Auto Express's approximately 77,000, against total production variously given as 91,849, 91,850 or 94,619. Peak North American sales came in 1974, at roughly 14,000 cars, by which point the federal engine carried a carbon canister, an anti-run-on valve, lowered compression and, from 1975, air injection and rubber overrider blocks. The consequence is that most surviving TR6s are left-hand-drive carburettor cars, and a genuine home-market PI car is scarcer than the totals alone suggest.

Quality, Reputation and the End Period ownership was not uniformly happy. Motor Sport's long-term TR6, bought in February 1973 for 1,798 pounds with hardtop, overdrive and soft top, went through a broken gearbox spacer washer at 15,400 miles, repeated tyre and brake trouble, water into the footwells, excessive crankshaft end float and a factory service at which the tappets, timing, greasing and brake adjusters were all found wrong. The injection itself, once rebuilt by the factory, gave no further trouble. Injected production ended in July 1975 and the last federal car was built on 14 July 1976, by which time the TR7 had arrived with a closed body, four cylinders and a monocoque. The TR6 was the last Triumph sports car with a separate chassis.

The crankshaft thrust washers are the engine's defining weakness. They are steel with a thin copper-nickel facing, they carry the load of a heavy clutch spring, and once the facing wears through the steel wears rapidly, the washer can drop into the sump and the crankshaft then bears directly on the main bearing cap - which turns a cheap job into a crankshaft or a block. Riding the clutch, resting on the pedal at junctions and starting the engine with the clutch depressed all accelerate it. Solid alloy replacements are the accepted fix. The Lucas injection is not fragile so much as intolerant: the original pump cavitates when hot, the fuel vaporising in the pump so that it spins without delivering, which stops the engine without warning, and modern unleaded fuel makes this worse. RevingtonTR notes that most surviving pumps have been rebuilt at least once with second-hand parts, and that Bosch pumps rated for the same 110 psi are widely substituted, mounted as low as possible to keep them flooded. Metering units wear and their oil seal to the block leaks. Elsewhere: differential mounts crack, driveshafts and their splines wear, gearbox layshaft bearings whine in the lower gears, clutch release bearings can last only 12,000 to 20,000 miles in hard use, rear hub bearings need specialist rebuilding, differentials leak, and overheating is common. Period build quality was poor enough that Motor Sport's own long-term car needed an independent specialist to correct what the factory service had left wrong.

The chassis decides the car. The frame is spot-welded from sheet steel pressings and rots from the inside, so surface condition tells you little. The rear trailing arm mounting brackets, the cruciform where the inner rails meet, the rear outriggers and the T-shaped pressing over the rear axle are the areas that matter, and swelling around the trailing arm bolts indicates rot working outward. The forward differential mountings crack and, left alone, tear their studs out of the frame; a clunk from the back of the car under power is the warning. Body corrosion follows the usual TR pattern - sills, floors, boot floor, front wings behind the headlamps, rear wing tips, the back of the B-post and the rear lip of the boot lid - and the three-layer sandwich where the rear wing meets the body traps debris. A recent respray on a car with no documented chassis work deserves suspicion rather than credit. Check the commission number against the claimed specification: CP and CR denote petrol injection, CC and CF carburettors, with L, U and O suffixes for left-hand drive, United States specification and overdrive. The commission plate stays with the bodyshell while engines and gearboxes move around, so it is the only reliable statement of what the car left Coventry as. Many PI cars were converted to carburettors when the Lucas system fell out of favour; establish whether the original metering unit and pump are present or merely stored. Have crankshaft end float measured before purchase. Confirm which overdrive is fitted and that it engages on the gears it should.

As of August 2026, classic.com records a Triumph TR6 market benchmark of $20,037 against an average recorded sale of $20,727, with tracked results running from $1,850 in August 2024 to $54,980 in July 2026 and around fifty cars listed for sale. Recent US results clustered close to the benchmark: $22,797 for a 1969 car in Massachusetts and $24,991 for a 1976 car in Pennsylvania, both in August 2026, against $13,500 for a 1974 car in May 2026. The Classic Valuer, aggregating 1,288 auction results with a 76 per cent sell-through rate and read in August 2026, gives a median of 15,246 pounds with a low of 2,690 pounds and a high of 62,207 pounds. The top of the market is thin and specific: RM Sotheby's sold chassis CF56401U, a 1976 car with 2,854 miles from new, original paint, interior and Michelin red-band tyres and a British Motor Industry Heritage Trust certificate, for $50,400 at Monterey in 2024. UK guidance read in August 2026 puts projects at 5,000-10,000 pounds, usable cars at 12,000-18,000, well-sorted cars at 18,000-24,000 and restored cars above 25,000 per Classics World, with Auto Express placing a good car around 13,000 pounds and a top car at 25,000. Classics World also notes left-hand-drive imports trading 10 to 20 per cent below equivalent UK cars, which is the clearest available price on the injection-versus-carburettor distinction.