As no one has mentioned either of these terms and can't figure out where the vibration comes from I am going to do what I hate, reverse engineer from another brand...

On Fieros... (I know forehead smack) the early years have the flywheels balanced to the crankshaft. On the later year the flywheel is neutrally balanced. Mixing the two doesn't end well. Is anyone aware of whether or not some mercedes flywheels are neutral or balanced to the flyweel?


Also, I too have seen 616 marinized motors, just not a 617 with a turbo.