There are only two types of E30 owners; those who have cracked pedal boxes and those who will at some point have a cracked pedal box.

If not bad enough, most don’t even realize their pedal box is already cracked and only discover it when knock on effects occur.

The problem is that the clutch master cylinder is mounted at an ever so slight angle; and what happens over time is that the engagement and disengagement of the clutch causes the mounting point to flex over and again. In almost all cases, the crack starts to form on the pedal box at a bend just above the clutch master.

Once the crack extends far enough, most people start experiencing an inconsistent feeling clutch engagement, and a crunchy feeling. The inconsistency comes from force being put into bending the pedal box instead of it engaging the master cylinder, while the crunching is from the two sides of the crack rubbing against each other. Wait a bit longer and the bending from the crack gets bad enough to break your master cylinder, or worse yet, breaks the plastic union feeding the clutch master brake fluid. If that happens you’ll be spending a long time cleaning brake fluid from your carpets (*not to mention brake fluid is hydroscopic and damages paint).

New pedal boxes are still available from BMW (PN 35111157719), however, these new pedal boxes will too fail at the same location.

Luckily someone on the E28 forums created a reinforcement bracket that also works on the E30 and takes about 45 min to install to eliminate the issue, even if your pedal box is already cracked.

Original E28 forum post:

https://www.mye28.com/viewtopic.php?f=4&t=103670

The original poster claims no affiliation with the version that Ireland engineering sells, and claims that they copied his design. What is important to know is that his version is objectively better as it has an additional stabilization tab, uses thicker material, has more consistent chromate application and comes with detailed instructions:

This entry was posted on May 19, 2023 at 11:03 pm and is filed under Interesting Stuff. You can follow any responses to this entry through the RSS 2.0 feed.