The Saab B engine is an inline four-cylinder car petrol engine developed by Saab Automobile. A redesign of the Triumph slant-four engine, the B engine displaced 2.0 L and first appeared in 1972. The B engine was used in the Saab 99 and 900 models. Saab began to phase the engine out in 1981. History In the early 1960s Rolf Mellde, Per Gillbrand and Karl Rosenqvist began work on a new 1.2 L inline four for the upcoming Saab 99. UK engineering and consultancy company Ricardo was involved in the project, and were also aware that Triumph in the UK were working on a similar engine. When Saab determined that developing their own engine would be too expensive and too risky, Ricardo put Saab in contact with Triumph. Triumph agreed to supply Saab with 50,000 engines per year for the new 99. Displacement was 1.71 L at first, and was increased to 1.85 L later. Saab had exclusive use of the slant-four for the first several years of production. Saab designed a new transaxle which utilized the case of the transaxle as its oil sump. The Triumph engine was turned 180° so that the clutch and flywheel were in the front. A consequence of this is that the "front"-mounted water pump would be facing the firewall/bulkhead and be inaccessible, prompting it to be relocated to the top of the cylinder block. In 1972 Saab brought production of the engine in-house to their Scania division at a facility in Sodertalje. An uncorroborated letter to the editor references a Saab press release of July 1970 that indicates that this was planned from the outset. Saab then 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 corresponding 2.0 L Triumph version. Saab redesigned the engine again in 1981, creating the Saab H engine. Technical features While the B engine carried features like bore centers and bearings over from the original Triumph design, it was a substantial redesign. Like the Triumph slant-four it was developed from, the B engine's block is made of cast iron, and the cylinders are canted over at 45° from vertical. The stroke of the earlier engine was retained, but the bore was increased to . Other changes from the Triumph slant-four included a new cylinder head with bigger valves, enlarged ports,