[gsmiller]

So, interesting discovery on my new-to-me 2004 C4S today: Turns out I don't seem to have the original engine in the car.

My mechanic was replacing my water pump for me as a preventative measure today, and it turns out the pump that was in there is the original, and a 997 part. My best guess is the original engine was replaced under warranty for the first owner with a later model M96 that used some of the 997 parts during transition.

Can someone shed a little more light on these engines? What years were the M96 engines using these hybrid 997 parts? I know the engine code would help a lot but I actually got rid of a lot of tools a couple years ago and don't have the means right now to get under the car and look.

I'd love to know to understand part compatibility better for future part orders, etc. Also, was the power/torque any different? Anything else of importance to understand? Any information would be helpful. Cheers!