The
Saab B engine is based on the
Triumph Slant-4 engine and replaced their aging two-stroke engine. When it was decided to develop a new
Saab model in 1964, the
Saab 99, the decision was also made to give it a modern four-stroke engine. A contract was signed with
Triumph to deliver their soon to be complete 1.5 liter engine to use in the Saab 99. The engine was enlarged to 1.75 liters before delivery started, and later enlarged again to 1.85 liters. In 1972 Saab begun domestic production of the engine, because of reliability problems with the Triumph-made units, effectively creating the Saab B engine.