I went to change my spark plugs and while I was at it, I stuck a boroscope in the cylinders to take a peek.
For some background, this is a 3.6L 993 motor swap in a '75 911s. My 1-3 bank has a bit more valve train noise and I'm still sorting out motor-swap issues (knock prone) which were couple other reasons I wanted to visually inspect the cylinders. I bought the motor rebuilt and I incorrected assumed the cam was timed accurately.
The marks (which I would assume is valve impact) on the cylinders are on cylinders 1, 2, and 3, coinciding with the side that has more "valve train" noise.
Also, what is with the orange discoloration? only saw this in cylinder 5.
Any thoughts, feedback, or input is much appreciated.
Thanks in advance.
