Specifications: 1973 Triumph Dolomite Sprint

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While Triumph’s Dolomite was a damn good car, it was no match for the BMW 2002 or Alfa GTV. To match these, Triumph needed something a little better. And that came in the form of the Dolomite Sprint. It may have taken a while, but the Brits had a true sports sedan - a high-performance four-cylinder ohc engine - with 16 Valves feeding a six-speed transmission - that seemed to contain all the verve and character of the Europeans. When launched the Dolomite Sprint had a price advantage over the Alfa and BMW such that it could rightly be considered in a class of its own.

But by 1975 it was retailing for roughly the same, and despite its excellent performance, the Dolomite Sprint was no BMW-beater, no Alfa-basher. Anyone who claimed such superiority, then or now, is simply being overly patriotic to British cars in general and Triumph in particular. Triumph created the Sprint by up-rating the power of the familiar (in Britain) Dolomite sedan, which had been around for some time. This neat, decidedly Triumph body (it looked rather like a scaled-down 2000) was renowned for its excellent interior dimensions despite relatively tight external measurements - 2450 mm (96.5 in.) wheelbase, 4110 mm (13 ft 6 in.) overall length and 1550 mm (61 in.). The makings for a compact but fast sporting sedan were all there.

To get the new power for the Sprint, the Rover-Triumph engineers took the Dolomite's 1854 cm3 slant four engine (also used by SAAB) and upped the capacity to 1998 cm3. They decided four-valves-a-cylinder was definitely the best way to go, but rather than employ twin overhead camshafts they stayed with a single cam. And rather than the SOHC being mounted centrally, actuating the Valves on both sides by means of two sets of rockers, the engineers placed the camshaft on the right-hand side of the alloy head so that it was immediately above and directly worked the inlet Valves. Rockers touching those very same cam lobes then crossed the top of the head to punch the exhaust Valves.

Why 16 Valves?

The combined area of the four largest Valves that can be squeezed into a given combustion chamber is greater than the area of the two largest that can be fitted. Increasing the valve area increases the amount of mixture that can be drawn into the engine and passed out of it during a given time. Hence you get more power. Backing up this potentially super breathing went fully-flowed inlet manifolding to carry the fuel from the twin 1.75 in. SU carburettors, and the exhaust was looked after by manifolding that led into twin pipes, merging only after they'd run past the gearbox area.

The power that came from this development - there was a 9.5 to one compression ratio - was a nifty 94.5 kW (127 DIN bhp) at 5700 rpm, and there was no less than 165 Nm (122 DIN lb/ft) at 4500 rpm. From two litres, in the early 1970s, that was impressive - although it was still not in the same class as the Alfa two-litre engine or the Lotus two-litre 16-valve. To cope with the increased power (the standard Dolomite had only 68 kW/91 bhp) the normal gearbox - the standard GT6 four-speeder - was replaced by the heftier transmission from the 2.5PI, and the final drive ratio was toughened. The standard gearing for the Sprint was 30 km/h (18.9 mph) 1000 rpm, but most seem to have come with the optional electric overdrive, which provided two extra speeds - on third and on fourth - and a final overdrive gearing of 38.1 km/h (23.7 mph) ; 1000 rpm, a point that meant cruising at 160 km/h had only 4200 rpm showing on the tacho.

The Dolomite had a basic suspension set-up, and the only real change for the Sprint was the upgrading of the wheels to 5.5J rims carrying 175/70HR 13 radial tyres. Otherwise, it was still upper wishbones at the front with lower links, coil springs and an Anti-Roll Bar. At the back, there was a live axle located by four links, with coil springs and an Anti-Roll Bar. Steering was rack and pinion and the brakes were servo-assisted discs and drums with a rear pressure-limiting valve.

On the Road

Road testers from the time noted that the engine fired easily but it asked for some miles before it let the choke be returned fully. When properly warm it immediately impressed with its low-down torque and oomph, responding instantly and heartily to a prod on the throttle and making the little sedan dart forward. There was no flat-spotting, no real peakiness, just a great deal of power and an eagerness to rev very rapidly indeed. In that way the car felt much like an Alfa two-litre or a BMW Tii.

Really fast acceleration times required a lot of revs and that brought both large amounts of wheel-spin and axle tramp - the inferior suspension design displaying one of its many deficiencies. During performance testing, Autocar managed times of 8.8 seconds from 0 to 100 km/h (0-62 mph) and 29 seconds to 160 km/h (100 mph) – and these were excellent, giving the car the edge on the GTV but not quite matching the Tii. Here in Australia that meant that the Sprint lagged way behind a Torana SL/R 5000.

The gear ratios were a little strange when you counted their results out on paper. First ran to a tall 65 km/h (40 mph), but second only went to 93 km/h (58 mph). Third then proceeded to haul on to 142 km/h (88 mph), exaggerating the limit of second gear. Of course, you then had overdrive on third, top and overdrive top to come. In practice, however, there was sufficient torque to mask the lowness of second gear and hide the gap between it and third. Leyland claimed 186 km/h (116 mph) for the Sprint, but most road testers and motoring journalists struggled to get much over 180 km/h (111 mph).

The Suspension Spoils The Fun

Fuel consumption was pretty good, considering the performance. Pounded really hard the car rarely gave less than 8.2 km/1 (23 mpg) and usually returned around 9.2 km/1 (26 mpg) with better figures coming with more frequent use of the overdrive ratios. But if the sheer acceleration of the Sprint was impressive, there were other aspects of the car's character that were disturbing. For example, if you turned in hard on a really quick corner, the tail was prone to hop off line. The slightest bump in the bend, when the Sprint was really hammering, made it pitch and twitch, and as the tail hopped the oversteer came on really rapidly, calling for very quick correction.

This characteristic - or rather, deficiency - persisted on the road. While it did have the benefit of counteracting understeer, it made the car feel insecure. Besides that, there was a feeling that the car was skinny, even though it had a relatively wide-stance 1371mm (54 in.) track. Although the steering was rack and pinion (and pleasantly light, with fair feel) the car seemed to move about around the steering when taken quickly through bends.

In the wet the roadholding was feeble. There was sudden understeer into bends, especially downhill, and very little power could be used before the tail snapped sideways. Just a touch on the throttle and the Sprint would spin its wheels. Worse still, many motoring scribes found the Sprint often unstable under brakes. The tail twitched and weaved and you had to work hard at the wheel to keep it all under control. It wasn’t that the brakes themselves were bad – in fact they were very good, having light pedal pressure, good feel and a lot of stopping power. We can only conclude that it was the suspension setup that was causing these problems.

An Impressive Competition Record

The Sprint did built up an impressive competition record in sedan racing in Britain. On the track, racing against sedans which understeer a good deal, the quick twitch into oversteer can be a decided advantage. The track cars had their respective suspension setups thoroughly sorted anyhow, the drivers were more than ready and able to cope with the lively tail and they had enough road to allow for correction. On the stock Sprint the ride was firm, but not unpleasant, although it could be nastily caught out by ruts and sharp bumps. Then, it would leap about a good deal, crashing and thumping. Over varying surfaces, it could develop a peculiar side-to-side jiggle.

Around town, the car would feel smooth and effortless, ride, steering, brakes and engine all combining well. You would learn not to take the engine right out to its maximum 6500 rpm too often because over 6000 rpm it became harsh and noisy. Better to stay lower down in the range and let the strong torque do all the work. The comfort and space offered by the Sprint, its driver facilities and its equipment could not be criticised. Although the body was quite small, the driving position was well forward so that there was a great deal of space - a lot more than in a Cortina, for example - and four people could spend long periods in the car – so often a requirement here in Australia where distances were much more than in the UK.

Behind the Wheel

The front seats, upholstered in Briny Ion cord, were simply designed and had low backs, but they remained comfortable, giving just the right amount of lumbar and lateral support. The rear seats were just as good, and the four doors allowed easy access to all four places. Scoring well over rivals, the Sprint had a driver's seat that tilted both front and rear to provide a good seating position. There was also a good deal of fore and aft travel, and the squab reclined. Then, when the seating position was determined you could reach down for the knob on the steering column and adjust the steering wheel: it moved in and out, and the column swung up and down. Thus, a very good driving position could be obtained by just about anybody although even with the wheel at its lowest position it still carried more rake than most people would have preferred.

There was plenty of room around the pedals to ensure comfortable long-distance driving, and all three worked nicely. But the distance between brake and throttle was just a little too great. Stalks looked after the minor controls (the usual Leyland stalks, as used in the Marina) so that there were no significant grumbles in that area. The gearstick was placed comfortably enough, and the electric overdrive switch was set into the big knob. There was only the sight of the word "on" or "off" on the switch to tell you if the overdrive was engaged or not, should you manage to forget. Thankfully, the Laycock overdrive switched in and out with remarkable smoothness, often it's undetectable.

The heater controls were arranged neatly in a vertical binnacle in the centre of the dash and provided a good range of climatic control. Ventilation was fine, boosted by opening the quarter vents if need be. The complete set of instruments worked neatly into the fascia and they could all be read easily, so long as the wheel rim wasn't in such a position that it obscured small outer dials. Strangely, there was everything but an oil pressure gauge, a mystifying omission in a car with such a high-performance engine.

A full-width parcels tray ran under the dashboard, and there was a lockable glovebox. The dash, along with the door cappings, was real wood, adding a truly British touch to the car and giving it an air of luxury not usually found in a car at the price pont or size. Other equipment that helped make the Sprint into an extremely complete package included thick pile carpet, leather-like fabric trim on the doors, swing-down grab handles, coat hooks, four ashtrays.

So in all these areas, the Dolomite Sprint was an impressive machine. It has a lot more room and comfort than a BMW Tii and an Alfa GTV (but not an Alfetta). It also has a great deal of performance and a fair measure of charm. The Alfetta didn’t have as much performance but it had a good deal more roadholding, far better handling, even more room and comfort and offered the real nitty-gritty - loads of driving pleasure. It is in that area that the Sprint, despite its many excellent points, fell down.