When accellerating hard, particularly in first gear above 4000 rpm, my R53 groans; it also happens in 2nd and 3rd on occassion. Seems to be coming from right under my feet, but that may just be an auditory hallucination. Sounds like straining of some component or like something's being stressed beyond its normal travel. It's defintely not an engine noise, but related to the drivetrain or suspension in some way. I have a TSW engine dampener installed, and I've increased the preload, but this hasn't fixed the problem. My hunch is engine mounts or exhaust system hangers or something like that. Could it possibly be a slipping clutch?

Any constructive input will be greatly appreciated ... TIA