Triumph TR6: An Enduring Classic

With the TR6, timeless looks meet rugged mechanicals.

The Triumph TR6 is the final evolution of a much-loved design that dates back to 1953. By the time the TR6 made its 1969 debut, however, the design had evolved to include a beautiful German-influenced body design and smooth-sailing, inline-six powerplant.

The TR6 was arguably one of the most successful sports cars to leave England, as nearly 100,000 units were sold during the 1969-’76 model run. Today, it’s a staple at any British car meet. The torquey engine, rugged mechanicals and timeless styling are hard to beat. Plus, the top goes down.

Last Classic
When Triumph added the 2.5-liter, six-cylinder engine to the TR4 to create the one-year-only 1968 TR250—a car known as the TR5 overseas—the brand immediately launched a styling update project with German body manufacturer Karmann. Triumph requested tooling 14 months later, and the TR6 was introduced on schedule. It came to market 15 months after the TR5’s arrival. The TR6 also came on the heels of the 1968 merger of Leyland and BMC.

Not much changed during the TR6’s production cycle. All years feature a healthy inline-six engine and classy interior. The squared-off trunk offers very reasonable carrying capacity. Plus, replacement parts and aftermarket accessories are only a phone call away.

The TR6 retained the basic shape of Giovanni Michelotti’s TR4, but the cleaner lines of the new front- and rear-end styling gave it a sharper image. The designers moved the headlights outboard, changed the grille and bumpers, and smoothed the hood.

The new, chopped-off tail provided better aerodynamics and more luggage space. The interior retained the traditional wooden dash and large dials, yet gained new seats with headrests.

The hallmark stiff ride was maintained as part of the marque pedigree, but handling was improved. Top speed was a respectable 109 mph, and drivers fell in love with the robust power at low revs.

Model changes throughout the seven-year production run were few. Triumph lowered the compression ratio twice, but the car’s stated horsepower always remained between 104 and 106.

Triumph did change the optional overdrive units for 1973, as the J-type replaced the earlier A-type. The most significant difference between the units involved when they could be engaged; the later version only operated on third and fourth gear, while the earlier version would also work when in second gear. Both overdrives are desirable options, as they make highway cruising much more pleasant.

Buying Advice
Like so many other British sports cars, buying a straight, rust-free car is paramount. However, restoring a TR6 can be easier than reviving other makes and models. Why? The body is attached to the frame with only about a dozen bolts, and Moss supplies body panels plus every part needed to restore the TR6 to show quality.

Moss technical expert Kelvin Dodd says rust is this car’s enemy, especially at the front and rear fenders and around the headlights and taillights. “There’s no easy way to fix rust at these common spots,” he warns.

Dodd recommends checking the rear wheel bearings, since they’re difficult to change out. He also advises getting a potential purchase up on a lift to check for fatigue where the differential meets the frame.

The TR6 performs well on the show field or during spirited drives.

Upgrading Performance
The best way to boost the TR6’s power is to supercharge the engine, says Dodd. Moss’ bolt-on supercharger comes with a carburetor, intake manifold, complete drive system with automatic belt tensioner, electric fuel pump, and water pump.

“The supercharger adds 40 extra horsepower to a stock engine, providing nearly a 50-percent boost in rear-wheel horsepower,” he adds. It features helical rotors and an internal, vacuum-controlled bypass valve for high efficiency and economic cruising. Carburetion is handled by a specially built Holley unit with passage modifications that improve operation during high boost and transition.

Further ultimate power enhancements recommended by Dodd include head porting, a fast street cam like the 270-degree duration camshaft, a set of British-made headers for better flow, and a performance exhaust system that offers dual stainless steel support for the back of the car.

To upgrade handling, Dodd advises a Moss-designed Tube Shock Conversion Kit for the rear of the car. It provides a dramatic improvement in ride comfort and car control. Tube shocks are also less expensive to replace than the original lever arms, he adds.

When it comes to further handling enhancements, Dodd explains that polyurethane suspension bushings will eliminate 90 percent of the deflection yet provide a quiet ride. He also recommends a rear anti-roll bar to improve cornering, along with lowered heavy-duty springs to reduce lean on the corners.

Moss’ new Differential Mount Stabilizer Cup damps road noise yet stiffens the mount, Dodd says. Their new Differential Mounting Support Blocks keep the differential located properly, since the original rubber mountings would often tear out or cause frame damage.

Wire wheels are a popular option as well as a common aftermarket upgrade.

Improved braking ability is necessary with upgraded performance, and Dodd recommends the Four-Piston Brake Upgrade kit to improve brake feel and stopping ability. He also suggests the new range of high-performance, semi-metallic and ceramic brake pads. Drilled and slotted brake rotors plus braided stainless steel brake hoses are also wise upgrades. The front axle-reinforcing kit stiffens the stub axles so they don’t push the brake caliper pistons out of position under cornering.

Dodd’s list of upgraded parts that improve the TR6’s performance and reliability includes a high-torque starter motor, high-performance Cobalt plug wires, and a stainless steel heat shield for the carburetors. Obtain Moss’ electronic conversion kit to upgrade the distributor from points to electronic switching with a PerTronix Ignitor.

For accessories and parts that are cool and attractive, consider Moss’ billet pedal cover set for the clutch, brake and accelerator. Moss’ factory front spoiler fits well. Panasport aluminum alloy wheels are also available; to get more tire under the car, use 16×7-inch wheels rather than the original 15×5.0- or 15×5.5-inch wheels. Make the engine sexy with a chrome foam-core air filter.

Popular Replacement Parts
593-030 – Borg & Beck Clutch Kit
581-040 – Brake Master Cylinder Assembly
586-511 – Brake Rotor, front 103/4-in.
835-055 – Water Pump with 1/2-in. groove
850-040 – Radiator
660-998 – Major Suspension Kit, front
855-325 – Rear Fender, LH
855-465 – Lower Front Panel
994-055 – Front Bumper
642-890 – Leather Seat Kit, black
640-150 – Convertible Top by Robbins, Black SunFast

Insider’s Info:
• Ten times more Triumph TR6s were sold in the U.S. than in Britain.
• Buy the best TR6 you can afford. Plenty of good cars are still out there.
• Triumph designed a new hardtop for the TR6 that nicely compliments the angular shape. The earlier TR4 top fits, but it has a more rounded profile.
• The chin spoiler first appeared on the TR6 for the 1973 model year, but Moss has a nice duplicate for earlier cars.
• The follow-up TR7 has nothing in common with the TR6.
• The British-market TR6 received fuel injection, while all U.S.-bound cars received twin Stromberg carburetors.
• According to the Cars That Matter price guide, a decent driver goes for about $8,000 to $12,000.