I recently bought an 88 Iroc, 5-speed and had a question about the horsepower. From the rpo codes I see the car has the factory LB9 and the factory mm5 5-speed. Doing research I see that this engine supposedly has 220 hp. However the tach is the lower redline tach, which would seem to indicate the weaker engine. Question is, other than someone Swapping in the wrong tach, is there any other explanation and is there any way to verify which cam is actually in the car?