I pulled the timing cover today and I found everything on the intake side was normal...I had reinstalled the VVT cam adjuster and set it correctly in the fully retarded position.

However, I found out how the AMG factory achieved the change in timing (from the C280 engine) on the exhaust cam. AMG reworked the cam sprocket. They elongated the holes for the three retention bolts and also drilled a new locating dowel hole.

If you have two holes available, you just know that someone is going to use the wrong hole. Yep, that's what happened...I should have use the new hole marked with a "U".

This is what I found (exhaust cam sprocket)...



I still don't know the basic timing setup for AMG M104 and how it varies from the C280 M104 setup. Any takers on this one?

At the moment I am turning the crankshaft over after trying different chain sprocket positions and trying by trial and error to achieve the AMG spec settings of:

1. Inlet valve opens 28 deg after TDC; and
2. Exhaust valve closes 16.5 deg before TDC.

I have the exhaust setting spot on.

But the 4mm drilled hole on the inlet sprocket will be way off when I set the cam to achieve the 28 deg event.

Appreciate any input guys!