Oldsmobile Toronado 1991–1992 Oldsmobile Toronado Trofeo 1992–1995 Oldsmobile Silhouette L67 SI Supercharged The Series I Supercharged engine went through 2 Supercharger revisions(Gen2&Gen3) and the horsepower improved between initial launch and the time that the Series II L36 was introduced. The M62 supercharger was manufactured by Eaton, for the GM 3800 SI engine. HP was rated at 205 for 1991-1993 engines (Gen2 supercharger) with a pulley, and 225 for 1994-1995 engines(Gen3 Supercharger). All of the additional horsepower for 1994-95 Gen3 supercharged engines was gained by using epoxy (not Teflon as commonly believed) coated supercharger rotors to improve efficiency, a larger supercharger inlet and throttle body, Thus the 1994-1995 utilized a pulley versus the pulley on the Gen2. The easiest way to spot the difference between the Gen2 and Gen3 is the smaller pulley and the ribs on the side of the Gen2 extend all the way down the sides, while the Gen3 ribs stay on only the top, they perform slightly differently and interchanging one without tuning may result in strange behavior of the engine. Redline on Gen3 engines is at 6000rpm but the ECM will shift at 5400rpm without performance shift enabled. Applications: 1991–1995: Buick Park Avenue Ultra 1992–1995: Oldsmobile Ninety-Eight Regency Elite (optional), Touring Sedan Pontiac Bonneville SE with H4U RPO, not badged - SLE (optional SC package), SSE (optional), and SSEi 1995 Only: Buick Riviera (optional) Oldsmobile Eighty-Eight LS (optional), LSS (optional) Series II Introduced in 1995, the Series II is quite a different engine. It is also by far the most popular of the 3800 family for its power, smoothness, fuel efficiency, and reliability, although the stroke for the 3.8 liter engine remained at , and the bore remained at . That said, the engine architecture was vastly changed. The deck height is shorter than the Series I, reducing weight and total engine package size. This required that the piston connecting rods be shortened , and the crankshaft was also redesigned. A new intake manifold improved breathing while a redesigned cylinder head featured larger valves and a higher compression ratio. The result was and , better fuel economy, and lighter overall weight (to ). This 3800 weighs only more than the all-aluminum High Feature V6 that currently dominates GM's six-cylinder applications, despite being an all cast-iron design. The new intake manifold greatly improved airflow. To meet emissions standards, an EGR tube was placed in the intake manifold