I was referring to the audible difference but they will also transmit more vibration into the car. Vibration in the car is really only noticeable at idle, more so with the a/c running or if the car is idling rough such as if you have a vacuum leak or something. I had the idle on my car bumped up to 900 rpm to reduce the SC'er rumble at idle well before upgrading the mounts though so I don't really get much vibration at idle but the lower stock idle speed will probably lead to more vibration as indicated by vI6cious.
Originally Posted by 330Cole
the vibrations in the car, or it is an audible difference?
04 IR 330i ZHP | ESS TS2+ SC | MagnaFlow "headers" | KMS 3.64 LSD | AST 4100 550/650| APEX ARC-8 18x9 | H&R front sway bar | Vorshlag camber plates, RTAB limiters | TMS subframe & swaybar reinforcements | UUC SSK & DSSR | UUC TM & TME | BW motor mounts | Dinan strut & shock tower bars | vaio 4-bolt oil pump