These bushes are recommended for track use only as solid diff bushes transfer an immense amount of diff whine and chatter into the cabin.
If you are looking to improve the handling dynamics of your E46 chassis, CMP strongly encourages starting with our Solid Subframe Raising Bushes paired with stock diff bushes. This is a proven combination that outperforms any poly setup yet maintains OE Noise Vibration and Harshness (NVH).
As a recomendation, the full threaded factory front diff bush can be swapped out for a generic partially threaded 10.8G, M14 x 1.5 x 60mm bolt from a local bolt shop. This prevents the possability of the threads gouging into the aluminium bore of the front diff bush over time.