From: bmw320i@earthlink.net Sent: Donnerstag, 18. Dezember 1997 03:22 To: Multiple recipients of BMW320i/323i-Digest Subject: Brake Upgrade Date: Mon, 15 Dec 1997 16:37:26 -0800 From: "Jack Roberts" Subject: Brake Upgrade Bill, the car I upgraded with the Girling 4-pot calipers is an Alpina B6 (323i body with 2.8 big block six). It has a standard 320i/323i master cylinder and a 323i proportioning valve. I upgraded the rear to E30 calipers at the same time. These have about 50% larger pads than the 323i so both ends remained balanced. As a result, the car now has the equivalent of E28 5-series brakes as for pad area albeit with the smaller rotors of the E21. It sounds to me like you have problems with your 320i's brakes that an upgrade will not solve. I've never had an E21 with rear drums but I would look for one of two problems (assuming you have no leaks, the system is bleed, and contains fresh fluid); either a weak brake hose or rear drums that have been turned too far oversize (beyond the limit). This was a common problem on 2002s where the owner or shop was trying to get one more brake job out of a set of worn out drums. Cheers, Jack