Series II started in which year?

Good afternoon,

Out '97 LeSabre has a Series II, 205 HP and gets good gas mileage. My '91 Reatta has an earlier engine, 165 HP. In which year did GM switch to the Series II engine.

Regards,
Jack C.

1995

The NA 3800 L36 started in 1995 in most C and H body cars as well as the Rivera.. The Lesabre for 95 still used the 170 Hp Tuned Port Injection series I... As well all of the supercharged engine for the 1995 model year were all series I's..

In 96 the 3800 Series II Supercharged was introduced... And the L27 Tuned Port Series I was dropped..

1997 was the first year for a series II 3800 in a W Body..