Well I drove it about 1.5 miles today at 30 MPH or less.
It seems to have a slight flutter sound in the valve train.
Now the camshafts & rocker arms are new and the compensators (hydraulic lifters) are used but I tested them by pushing down on them with a large hammer handle as demonstrated in the manual.
All passed and I went through the valve clearance checks with the special tool and adjusted the shim caps as required. Many of them are brand new and some are used with no distinguishable wear. The heads were rebuilt about 5,000 miles ago and I had them vacuum checked to make sure of the seats being tight.
I also fine tuned the cams per the manual.
My left cam is right on 22 degrees and my right cam is on 19 degrees rather than 20 as that is as close as I could get with the offset keys.
Right side is set tighter to begin with when the valve train and chains are new so it will wear towards the 22 degree mark per the manual.
This is not a terrible flutter but still noticeable and mostly when cold.
I am sure it needs to wear in some but I am wondering if a lifter is not as good as it should be somewhere in there.
jimm1009

1991 US 420SEL