in diameter and are operated by the camshaft lobes through bucket tappets, while the exhaust valves are in diameter and are operated through rocker arms. The design of the cylinder head won a British Design Council award in 1974. Capacity was increased to , and larger HS6 SU carburettors were fitted. Other changes to the Sprint engine included a duplex timing chain and alloy timing cover. The big-end journals were also cross-drilled. The engine was expected to make 135 bhp, and King returned from holiday "to find an engine running on the bed giving 150 bhp at the first build." Hence, it was initially intended to be named the 'Dolomite 135'. This was changed to 'Dolomite Sprint' and published reasons vary. One oft-repeated rumour is that production lines could not guarantee 135 bhp. However according to Matthew Vale, it was during development that Triumph switched to measuring power from imperial (SAE) to metric (DIN), which calculated outputs approximately 5% lower. In this case 135 bhp SAE is 127 bhp DIN. The Dolomite Sprint has been described as "the world's first mass-produced multi-valve car". Multi-valve engines had first appeared in 1912, with the most recent prior to the release of the Sprint engine being the Cosworth BDA (1969) and Lotus 907 (1972), but they had not been not used in mass-production vehicles until after the introduction of the Dolomite Sprint. The 16-valve 2.0 L engine was also used in a small number of prototype and pre-production TR7 Sprints built at Triumph's plant in Speke during 1977. Saab B engine In 1972 Saab brought production of the 1.85 L slant-four in-house to their Scania division at a facility in Södertälje. An uncorroborated letter to the editor of Motor Sport magazine references a Saab press release of July 1970 that indicates that this was planned from the outset. Following the transfer Saab embarked on a redesign of the engine that resulted in the Saab B engine. Displacement increased to 2.0 L, but the bore diameter was smaller than the enlarged Triumph version, resulting in a swept volume of . Saab's B engine shared much with the original Triumph design, including bore centres and bearings, but some previously problematic features, such as the water-pump and its seal, were redesigned. Slant-four variants Motorsports The 16-valve Sprint engine was raced in FIA Group 1 and Group 2 in Dolomite Sprints prepared by Leyland Special Tuning at