Technical Paper
Saturn DOHC and SOHC Four Cylinder Engines
1991-02-01
910676
This paper describes two 1.9L four cylinder engines developed for the new Saturn vehicles introduced in the Fall of 1990. A single overhead cam (SOHC) 2 valve/cylinder single point fuel injected (TBI) design is utilized as a base engine with a dual overhead cam (DOHC) 4 valve/cylinder multi-point fuel injected (MPFI) configuration selected for an optional derivative. Market objectives for the SOHC engine included exceptional driveability achieved by high torque at low engine speeds combined with excellent fuel economy. Objectives for the DOHC engine included excellent driveability characterized by high torque at low engine speeds as well as good high speed power and good overall fuel economy. Both engines were developed in conjunction with specific automatic and manual transmissions to achieve fully optimized powertrains. One of the strategic technologies selected was the lost foam casting process.