Triumph TR7

Introduction

ONLY THE AMERICANS had the initial pleasure of the long-rumoured TR7, which went on sale in the USA in Febrary, 1975. Contrary to expectations, the ultra-modern looking, wedge-shaped, 2-litre, two-seater did not initially replace the TR6, and was sold alongside the TR6 in USA British Leyland showrooms.

Mechanically the TR7 was a conventional front engine, rear-wheel-drive Dolomite, a disappointment for those expecting a mid-engined layout. But the body, which resulted from a futuristic sketch made by Austin-Morris stylist Harris Mann, had lines in keeping with the 1970s and 1980s fashions and bore more than a passing resemblance in some respects to British Leyland's SRV2 Marina-based safety car.

Its frontal aspect was attractive, particularly in the flesh, however the car was perhaps a little less photogenic. Unfortunately the rear end looked as though it had been shunted by bus, largely because of the American regulations relating to lights and "5 m.p.h. bumpers".

The centre section, with dummy fluting on the rear quarter panel, was reminiscent of the mid-engined Fiat X1/9, and the steeply sloping, large area windscreen was a Solbit fixed laminated screen, which did not use a conventional rubber seal, the windscreen fitting flush to the body, minimising wind noise.

Retractable 7-in. round headlamps, their action powered by electric motors, allowed the designers to adopt the low, wedge-shaped nose, though this created a lot of wasted space ahead of the cross-flow radiator. There were pronounced lips over the wheel arches, the forward-hinged bonnet was louvred and a curved flare in the side panels was intended to give an impression of speed.

But "Speedy" the TR7 was not, the maximum speed being 107 m.p.h., but on the plus side at least it was relatively economical. The in-line, slant-four Dolomite engine was fitted with the single camshaft, eight-valve head of the standard 1854-c.c. Dolomite, then using the 1998-c.c. block from the Dolomite Sprint, fed through 175CD instead of the Dolomite's 150CDS Stromberg carburetters.

The engine had a compression ratio of 8-to-1 instead of 9-to-1, and used a new Lucas miniaturised transistorised magnetic impulse ignition system which fitted inside the contactless distributor.

After the cars initial launch there were much quicker derivatives established in Europe, such as the Dolomite Sprint-engined version utilising Bosch fuel-injection. The drive line was identical to the Dolomite in everything except length of the propshaft: the same 8½-in. diameter clutch, even the same gearbox ratios and 3.63-to-1 final drive. Dolomite suspension layout is followed, too. This meant MacPherson struts, coil springs and an anti-roll bar at the front, while the live rear axle was suspended by the Triumph four-link system with fore and aft location provided by two longitudinal trailing arms mounted to the body and the underside of the axle casing and two semi-trailing arms mounted to the body and the top of the axle casing.

Carrying Over The Dolomite Suspension Setup

Coil springs were carried on the trailing arms and the telescopic dampers were mounted to the floor-pan and the rear of the axle. The use of this arrangement guaranteed a comfortable ride from its long suspension travel and moderately soft springing, on the downside however there was little attempt to improve the axle location to obviate the poor traction which the Dolomite, particularly in Sprint form, suffered from.

The front disc brakes were an inch larger than those of the Dolomite, being of 9¾ in. diameter, but the same 8 in x 1.5 in. rear drums were employed. A split circuit hydraulic system was fitted, the rear one having a line-pressure reducing valve to maintain balance between front and rear brakes, and a Lockheed direct-acting servo reduced the right-foot's effort.

The most disappointing aspect of the TR7 was the poor utilisation of space within what was quite a large car: at 13 ft. 8.3 in. long it was 2.3 in. longer than the Dolomite while it was no less than 4.45 in. wider than the Dolomite, being 5ft. 6.2 in. wide. Yet this was a strict two-seater with very little space even for oddment stowage in the cockpit. All the space between the cockpit and illuminated boot was taken up by fuel tank and double bulkheads and, like the TR6 and the Stag, the boot was ridiculously shallow in relation to the depth of the car tail, the spare wheel and extraneous bodywork taking up all the space beneath the boot floor. The luggage space was also shallow front to back, though it ran the full width of the car and had a couple of unprotected bolts ready to maul luggage.

The driver and passenger were not troubled by lack of personal space and were surrounded by what was then one of the most atttractive interiors to be put into a modern sports car. The seats were the usual very comforrtable, Triumph-style, broad-cord trimmed ones and deep pile carpets trimmed the floors, very high sills and bulkheads. You sat in the TR7, not on it, burying your feet into deep wells on the driver's side of which the pedals were none-too-well spaced, particularly on left drive examples.

One Of The Best And Most Functional Interiors Of Any Sports Car

At launch Triumph went to great lengths to promote the interior, claiming it to be "one of the best and most functional interiors of any sports car". All the major functions were controlled by the brilliant Triumph switch-gear on the steering column and less freequently-used switches were within easy reach on the facia or centre console. The steering wheel was trimmed in imitation leather and had a massive crash pad in its centre. The comprehensiveness of the instrumentation was spoiled by the lack of an oil-pressure gauge. All the instruments and panel and warning lights were built into one printed circuit unit.

The air-blend heating system was also one of the best employed in a sports car, particularly a British sports car, while air-conditioning was offered as a factory-fitted option. For even better ventilation, a full-width sun-roof was made available as an option shortly after launch, but there was not be a full-open version, as the TR7 was designed at a time when the Americans intended to ban open cars by 1975.

Buying A TR7 Today

The Triumph TR7 can represent good buying to the classic car enthusiast. Why?, well the reliability and quality control problems that dogged the car during its production life should be well sorted by now - however any potential purchaser should look very closely at the car on offer.

The TR-7 engine is a 95 hp iron block, aluminium head 2L straight-4 matched to 4 or 5 speed transmission. Top speeds are around 110 mph, 0-60 in 11 sec, and automatic transmissions were available from 1979 until the end of production for both the TR-7 and the TR-8. Fixed head TR-7's were manufactured from 1975-1980, with convertibles being manufactured from 1979-1981. The TR-7 straight-4 engine is not one of the finest that Triumph ever made.

The bottom half is made from cast iron, the top half from aluminium. Early models experienced problems with warped heads, head gasket trouble, etc. Many TR7/8's are prone to electrical problems, and early TR-7's have a rather tarnished reputation due to quality control problems (Quality control seemed to improve after 1979).