I know series I engines with 170hp were made up to 1994, and 1995 began the series II engine with 200hp. The problem is that I had a GM mechanic look at my engine and he told me it was a series II. He said series one had a metal plenum and series II had the plastic plenums. I have a plasitic plenum. Also, the car has dual exhausts if that matters. I guess I would like to know if I have the 170hp engine or the 200hp engine.


Can anyone explain this to me?

You have a series I, metal plenums were only used in 92 some. The plastic ones in 93-94 weren't prone to failure like this though.

Power ratings for L27
170 Horse
225 Lb/ft

L36
205 Horse
230 Lb/ft

It has more HP because the rev limiter is raised, and the torque is in higher RPMS.