I recently changed the supercharger pulley on my 05 MCS, excellent mod ! In order to do this I had to remove the driver side engine mounting bracket (UK car) - after I put it all back together I noticed that the car seem to feel a little loose - hard to explain but the steering felt easier to turn and seemed to have a little more bump steer than usual. I thought maybe I was just noticing it more because of the increased power, but after a few weeks I was sure something wasn't quite right.
Last weekend I installed the superflex engine mount bushes on all three mounts, I jacked the car up and undid all the mounts so everything was loose, I then fitted the bushes one at a time.
When I got to the gearbox mount (the upper engine mount was already fitted) I managed to fit the bushes and bracket to the mount but the bracket was out of line with the body of the car. This wasnt much, maybe a few mm, rather than undo the other mounts I got a friend to push the engine over by hand so the holes lined up (a fair amount of effort was required, but no bar or lever was used). All ok and everything went back together fine, when I drove the car it felt totally different again - much stiffer and steering felt tighter - I thought maybe it was just the bushes making things feel different but after a few days I was sure something had changed.
When I looked under the bonnet I noticed that the upper engine mount nut was in a different position than before (only a few mm again) so as an experiment I jacked the engine back up and lossened the mounts, then when I dropped it back into position the nut was in a different place again - took the car out and it felt loose again.
It seems to me that if you pull on the engine when dropping it onto the mounts it almost acts like a structural component and pulls the whole car together just alittle bit (maybe acting like a brace) - has anyone else noticed this ?? I promise you, on my car the difference is noticeable. You can just drop the engine into its natural position and the car feels loose, but you can also stretch the engine across its two mounts (left/right) and it seems to tighten the car up - anyone else experienced this, am I suposed to stretch the enigne between the mounts when refitting ???