Dolomite Sprint
| Production | 1973–1980 22,941 made 1973 - 5,446 1974 - 4,232 1975 - 3,589 1976 - 4,035 1977 - 2,554 1978 - 1,352 1979 - 1,240 1980 - 493 |
|---|---|
| Engine | 1,998 cc (122 cu in) Straight-4 SOHC with 4 valves per cylinder |
Although the Dolomite proved to be refined and rapid, competitors such as the BMW 2002 had a performance advantage which was costing Triumph dearly, both in terms of sales and prestige. To remedy this, Triumph unveiled the Dolomite Sprint in June 1973, although the launch had been delayed by a year; it had been due to go on sale in 1972.
A team of engineers led by Spen King developed a 16-valve cylinder head with all of the valves being actuated using a single camshaft rather than the more normal DOHC arrangement. The capacity was also increased to 1,998 cc (122 cu in), and combined with bigger carburettors the output was upped to 127 bhp (95 kW). This represented a significant increase over the smaller 1850cc variant, however it fell short of the original target of 135 bhp (101 kW).
Despite BL engineers being able to extract a reliable 150 bhp (112 kW) from test engines, the production line was unable to build the engines to the same level of quality, with production outputs being in the region of 125 bhp (93 kW) to 130 bhp (97 kW). This led to the original model designation, the Dolomite 135, being replaced at short notice with the Sprint name.
As a result of this new engine the Dolomite Sprint has a claim to be the world's first truly mass-produced multi-valve car, and the design of the cylinder head won a British Design Council award in 1974. Performance was excellent, with 0–60 mph taking around 8.4 seconds, with a maximum speed of 119 mph (192 km/h). Trim was similar to the 1850, with the addition of standard alloy wheels (another first for a British production car), a vinyl roof, front spoiler, twin exhausts and lowered suspension. By now seats were in cloth on the 1850, and these were also fitted to the Sprint.
Due to the increase in power brought by the new engine, the rest of the driveline was upgraded to be able to withstand the extra torque. The gearbox and differential were replaced by a version of those fitted to the TR and 2000 series cars, albeit with a close ratio gearset in the gearbox. The brakes were upgraded, with new pad materials at the front, and the fitment of larger drums and a load sensing valve at the rear. Other changes over the standard Dolomite included the option of a limited slip differential. The optional overdrive and automatic transmission from the 1850 model were also offered as option on the Sprint. Initial models were only offered in Mimosa yellow although further colours were available from 1974.
At launch the Sprint was priced at £1740, which compared extremely well to comparable cars from other manufacturers. Prospective buyers would have been hard pressed to justify the extra £1000 cost of the BMW 2002 Tii, which offered similar performance. The four-door practicality of the Sprint also made it a very attractive proposition for the young executive choosing his first company car. The press gave the Dolomite Sprint an enthusiastic Reception. Motor summarised its road test (subtitled "Britain leads the way") with glowing praise:
...the Sprint must be the answer to many people's prayer. It is well appointed, compact, yet deceptively roomy. Performance is there in plenty, yet economy is good and the model's manners quite impeccable ... Most important of all, it is a tremendously satisfying car to drive.From May 1975 overdrive and tinted glass were fitted as standard. In addition, all Sprints were fitted with a body side trims, a plastic surround for the gearlever and a driver's door mirror. Headrests were now available as an optional extra. From March 1976 headrests, a radio and laminated windscreen were fitted as standard. In 1978 laminated windscreens became a standard fitment and in 1980, to comply with UK legislation, twin rear fog lamps were also fitted as standard.
As with many other British Leyland cars of the period, a number of "Special Tuning" options were available for the Dolomite Sprint, offering dealer fitted upgrades to the car that included larger carburettors, freer flowing exhaust systems, and competition camshafts. These upgrades were designed by the factory race team and offered in order to homologate the tuning parts for competition purposes.
In 1977, a number (probably 62) of Triumph TR7s with the same Sprint engine were manufactured as pre-production cars at Speke, Liverpool. However, this TR7 Sprint variant was cancelled with the closure of the Speke assembly plant in 1978.
Read more about this topic: Triumph Dolomite