Closing date July issue -> May 19
De Triumph Slant-four engine.
De Triumph slant-four. The engine is known for its history with Saab. For those unfamiliar with the power unit: this is an inline four-cylinder petrol engine that is driven by the Triumph Motor Company was developed and first appeared in the Saab 99 in 1968. The first engine had a displacement of 1705 cc and was designed according to the SOHC principle. The first Triumph It was not until 1972 that this engine appeared on the scene: the Dolomite 1850.
Design
The design of the engine, led by Lewis Dawtrey and Harry Webster, utilized a cast-iron block positioned at a 45° angle, aluminum pistons, and a single overhead camshaft with eight valves, which allowed for a compact construction and a low hood. Triumph developed a special 16-valve version for the 1973 Dolomite Sprint, in which all valves were operated by a single camshaft; this innovative design won a British Design Council Award and made the Dolomite Sprint the first mass-produced car with a multi-valve engine. The slant-four was further used in the TR7 and the Panther Rio, where Saab used the engine exclusively in the early years and rotated it 180° to couple it to their transaxle.
History
In 1963 analyzed Triumphchief engine designer Lewis Dawtrey presented future engine technologies and proposed a new engine family: a range of OHC engines in both inline-four and V8, from 1,5 to 3,0 liters, which existing Triumph-could replace motors. Development began internally at Triumph under the leadership of Dawtrey and Harry Webster. At the same time, Saab was working on its own four-cylinder engines for the Saab 99, but it proved too expensive and risky to develop them in-house. Through the British engineering firm Ricardo, Saab came into contact with Triumph. Triumph supplied 50.000 slant-four engines to Saab annually. Saab rotated the engine 180°, moving the clutch and flywheel to the front and simplifying connection to the drivetrain. The first Triumph With this engine was, as described in the introduction, the Dolomite 1850 (1972). Later came the sporty Dolomite Sprint (1973) with a 2,0-liter engine and the 16-valve cylinder head. This version is often described as the first car with multi-valve technology. Other applications were the TR7 (from 1975) and the Panther Rio (1975–1977). Production of the slant-four ended when the TR7 and the Dolomite Sprint were discontinued in 1981.
Technical features
The slant-four features a cast-iron engine block with 45° tilted cylinders, allowing the same tooling as for the V8 to be used and enabling a lower hood. The crankshaft is five-bearing and the aluminum pistons have three rings. The cylinder head is made of aluminum with wedge-shaped combustion chambers, and a single overhead camshaft operates eight valves via bucket tappets.
Sprint 16-valve engine
For the Dolomite Sprint (1973) developed Triumph a unique 16-valve cylinder head, in which all valves were operated by a single camshaft. This design won a British Design Council Award in 1974. The engine had a displacement of 2,0 liters and produced approximately 135 hp. The 16-valve was also used in some pre-production TR7 Sprint models in 1977. Finally: The 'Slant-Four' was also further developed by Saab during the 1970s, which developed the B-engine (two-liter) from the 1850 power unit.
In those years, I drove a Triumph Dolomite with the 1850 Stanpart engine, followed by a Saab 99, with the same engine in reverse.
The Saab used 1 liter of oil per 100 km, so it wasn't a keeper.
Later I had a 900 with a 2.0L, 500.000 km. Now I still have a 9-3 and a 9-5, the latter with a B235 and 230 hp. By now also at 335000 km and owned for 14 years.
These Saab 2-liter 8-valve engines, based on the Triumph, are engines that the modern automotive industry could learn a thing or two from in terms of lifespan.
More than 500.000 km is not uncommon; once, during a service, I was given a replacement Saab that had clocked 860.000 km, and it was still driving fine.