[Eplatvoet]

My BDR has a vibration that seemed to be coming from the engine. I had the engine and everything attached to it rebalanced (a long story, the original builder was a real piece of work) so that it all is perfectly smooth.... Except for this vibration which is mostly felt between 2000 and 2500 rpm. This occurs when the car is idling, so it is not the tires (had them replaced and balanced anyhow) and it is not the engine mounts.

Sooo... The theory is now that it might be the side pipes. Could this be a combination of incorrect timing (it is now TDC) with "untuned" exhaust headers setting up a resonance in the pipes? We are at the end of our wits here...