Triumph TR7 Tire Pressures

• The ideal Triumph TR7 tire pressure is 24/28 PSI PSI.
• To find the ideal tire pressures to match your car's year, model, and chosen tires follow the link to our Triumph TR7 Tire Pressure Guides.

• Our recommendation for 4-speed Triumph TR7 tires is the 175/70 VR 13 PIRELLI CINTURATO CN36.
• For the 5-speed TR7 from 1979, we recommend 185/70 VR 13 PIRELLI CINTURATO CN36.
• To see more information on Triumph TR7 tires follow the link to our Triumph TR7 Tire Section.
• You can also see a range of period Triumph TR7 Tire Pressure Guides from tire manufacturers to check your precise model of TR7.

Triumph TR7 Tires (1975–1981)

The first TR7 from 1975 fitted 175/70R13 Goodyear G800S or Michelin XV as original equipment. Neither of these tires are currently in production.

Currently we recommend fitting 175/70 VR 13 PIRELLI CINTURATO CN36 tires. See our PIRELLI CINTURATO CN36 Tires section for more information.

In the 175/70R13 size category, the Dunlop SP Sport AquaJet, also available in 175/70R13, serves as a solid choice for more steady drivers. However, we recommend the CN36 over the AquaJet, as it offers superior overall performance.

From 1979 the 5-speed model of TR7 fitted 185/70R13 tires, we suggest fitting the 185/70 VR 13 PIRELLI CINTURATO CN36.

Triumphs V8 version of the TR7; the TR8, also fitted 185/70 VR 13 PIRELLI CINTURATO CN36 or the 185/70R13 Dunlop SP Sport Aquajet.

Today the 185/70R13 Dunlop SP Sport Aquajet is available, as is the 185/70 R 13 Michelin XDX. Both are good tires, however we find the CN36 to be the most sporting and capable.

1975-1979 TR7 models that fit 175/70R13 as OE could be fitted with 185/70R13 if you prefer a wider tire, however we would recommend fitting the car's original size.

PIRELLI CINTURATO CN36 Tires

In 1968, the tire industry witnessed a significant innovation when Pirelli launched the CN36 model of the PIRELLI CINTURATO™, their pioneering foray into the sector of low-profile radial tires. This tire, notable for its 70% profile, swiftly rose to prominence and became emblematic of the era's most thrilling vehicles, such as the Porsche 911 and the Ford Escort Mexico.

The CN36, a trailblazer in Pirelli's high-performance tire line-up, was tailored to improve the driving dynamics of the era's nimble rear-wheel-drive sports vehicles. It presented an optimal solution for drivers looking to shift from traditional full-profile tires to the newer low-profile options without sacrificing driving performance. The CN36's distinct rounded shoulders were meticulously crafted to align with the vehicular advancements of that period.

Present-day reproductions of the CN36 maintain their legacy, now with the inclusion of Porsche's 'N' certification, positioning them as a prime option for potent vintage sports cars.

One of the unique benefits of Pirelli's CN36 is its period-specific carcass structure, which is ideally matched to vintage automobiles. Conversely, other tires with dimensions like 175/70VR13 and 185/70VR13 possess modern tread patterns and carcass constructions that cater to contemporary vehicles and do not meet the 'V' speed rating that the PIRELLI CINTURATO™ CN36 achieves.

The 'V' speed rating is indicative of a tire's capability to handle sustained speeds of 149 mph for one hour in testing conditions, making the CN36 more than capable of handling the speeds and forces generated by the TR7.

Triumph TR7 Innertubes

Our period fitment guides suggest that the TR7 fitted tubeless wheels throughout production. Innertubes are optional for these wheels, providing that the rims are still airtight and in good working condition. If you do decide to fit innertubes, we recommend Michelin Tubes. In our experience, Michelin Innertubes are of the highest quality, they last the longest, heat up the least inside the tire, and provide less failiures than all the other brands we use.

The correct sized tube for 175/70R13 and 185/70R13 is 13E, so our recommended tube is the Michelin 13E innertube.

Triumph TR7 History

The Triumph TR7, a distinctive sports car manufactured by British Leyland from September 1974 to October 1981, became a notable chapter in automotive history. This vehicle, characterized by its wedge shape and swage line, was initially produced at the Speke, Liverpool factory before moving to Canley, Coventry in 1978, and finally to the Rover Solihull plant in 1980​​.

Design and Performance

Designed by Harris Mann, the TR7's unique shape was a departure from previous Triumph models. It had dimensions of 160 inches in length, 66 inches in width, an 85-inch wheelbase, and a height of 49.5 inches for the coupe, which weighed 2,205 pounds​​. The power came from a 1,998 cc eight-valve four-cylinder engine, delivering 105 bhp at 5,500 rpm and a maximum torque of 119 lb⋅ft at 3,500 rpm. There was a notable power difference in the North American version, which produced only 92 bhp due to emission regulations. The car was available with a four-speed manual gearbox initially, later adding a five-speed manual and a three-speed automatic option​​.

Production and Variants

A total of 112,368 coupé/hardtop and 28,864 cabriolet/roadster units were produced, along with a special TR8 model that featured a 3,528 cc V8 engine​​. The TR7 was initially offered only in the U.S. market before being released in Europe and Britain. The car underwent various changes during its production life, including modifications to the interior trim, such as the introduction of "tartan" check inserts and changes in door card lighting​​.

Development Challenges

The TR7 faced several developmental challenges. During its development, BLMC (British Leyland Motor Corporation) was under pressure to create a vehicle that was both quick and reliable to compete with cars like the Datsun and Porsche. This led to the adoption of a front engine, rear wheel drive layout, which was considered more reliable and easier for quick fixes. The TR7's design was influenced by the need for a vehicle to meet U.S. crash regulations, leading to a sturdy construction with an emphasis on safety​​.

Market Reception and Improvements

Upon its UK debut, the TR7 was met with mixed reactions. Performance-wise, it was considered adequate but not particularly powerful. The chassis was praised for its effectiveness, but the car was noted for lacking in power. The styling, while controversial, did raise awareness of the model. Early quality issues and labor strikes at the Speke factory led to a transfer of production to Canley, resulting in improvements in assembly quality and minor changes to the car, including the addition of a 77mm five-speed gearbox, a wider range of colors, improved interior trim, and a bonnet power bulge​​.

Legacy

The TR7 was marketed as a more modern and safety-conscious sports car, differing significantly from its predecessors in terms of design and engineering approach. Despite the challenges it faced, including labor disputes and quality issues, the TR7 left a lasting impact as a symbol of a transitional era in British automotive history, representing both the aspirations and the difficulties of the British car industry during the 1970s.