The Cummins L-series engine is a straight-six diesel engine designed and produced by Cummins. It displaces 8.9 litres (543.1 cu in), and began production in 1982 as the L10 at the Jamestown Engine Plant in Jamestown, New York. After lengthening its stroke from 136 to 147 mm, its displacement was enlarged to 10.8 litres and the engine renamed M11, later ISM. The ISL 9 and current L9 engines are not related to the L10 engine, but instead based on the smaller C-series platform with the 135 mm stroke of the C8.3 enlarged to 144.5 mm, together with 4 valves per cylinder, giving it 8.9 litres displacement.