The LD2 was the standard version of the Quad 4 and the first incarnation having been introduced in 1987 for the 1988 model year. In base form, the Quad 4 put out 150 bhp (110 kW) from 1988 to 1989 and 160 bhp (120 kW) from 1990 to 1992. GM was able to produce the 160 bhp (120 kW) with no turbo, nor an EGR system to pass emission standards; it required a 9.5:1 compression ratio. The base Quad 4 saw several slight changes during its production run including different crankshafts, cams, and manifolds, all meant to increase torque and quiet NVH. There was also a transitional version of the LD2 in 1995, which displaced the same 2.3 liters as the early Quad 4 but featured the dual balance shafts of the later 2.4 L LD9 Twin Cam.
Applications:
- 1988–1991 Oldsmobile Cutlass Calais
- 1992–1994 Oldsmobile Achieva
- 1988–1994 Pontiac Grand Am
- 1988–1991 Buick Skylark
- 1990–1991 Oldsmobile Cutlass Supreme
- 1990–1991 Pontiac Grand Prix
Read more about this topic: GM Quad-4 Engine