The W41 was the highest output Quad 4. The 1991–1992 W41 were rated at 190 hp (140 kW), while the 1993 W41 was rated at 185 hp (138 kW) as a result of the first round of exhaust port size reduction to improve emissions and other changes to the Quad 4 architecture to reduce NVH (noise, vibration, and harshness). The additional 10 hp (7.5 kW) came from longer duration cams and a different PROM. A part of the W41 drivetrain was a specific version of the HM-282/NVG-T550 with a gear set otherwise unavailable. All W41 five-speed transmissions had a FDR (final drive ratio) of 3.94:1 whereas the 1988–1992.5 LD2 and LG0 transmissions all used a 3.61:1 FDR; the 3.94:1 FDR was used on all 1992.5-1994 LG0 transmissions, but retained the standard HM-282/NVG-T550 gear set.
W41 applications:
- 1991 Cutlass Calais Quad 442
- 1992–1993 Oldsmobile Achieva SCX
Read more about this topic: GM Quad-4 Engine