Trying to figure out what can be done to reduce the vibration level of my newly rebuilt W11. New mounts, stock damper (ATI damper in plans), new (rebuilt) accessory belt tensioner, no AC. Idle RPM is at 750.
When I was rebuilding the engine, I weighed each piston / rod and they all were within +- 10 grams from each other.


Is this normal? My wife complains that it works like a tractor No codes, otherwise works fine.

Looks normal to me. Neither one of my 2 Minis idles that low.

I would be concerned that a newly rebuilt motor was making that much noise. Your rpms are around 100 too low that may be contributing to the vibration. Rev it to 850 (normal) and see if that stops the vibration. BTW - the ATI damper should help.

I'll try to increase idle RPM to 850 via INPA (I know it can change it temporarily, but probably, permanently too). I am also planning just to reflash DME using the stock firmware (just to exclude the case if the SW was altered by the previous owner).

Ok, I think I've fixed it! Here are new videos, after the fix:

And the cause was..... Yep, the front (right) hydraulic engine mount! I already replaced it before, but I used an aftermarket mount from RockAuto ("Beck&Arnley" one). It seems like it is.... crap! Once I put a new OEM one back (Corteco), vibration inside the car is gone. I didn't even need to replace the vibration damper (at least, not this time).

Just have drove it for about 30 miles of mixed traffic.... Wow, what a difference that engine mount made! Finally, this R53 is riding the way it should!