Rear X Brace

I wanted to install true rear coils into the back, for more control. To do this you need to reinforce the strut towers as they are notoriously weak in the E46. You can install the Z3 plates, but these are realistically not enough. For a purpose built car, the roll cage should help with the reinforcement. Since my car is currently still road legal, im not installing a roll cage just yet, for comfort reasons. The temporary solution I chose is to install a bolt in rear X brace which reinforces the strut tower to the subframe.

To install the X Brace you need to remove the rear subframe bolts, and drill through the bolt hole into the boot with a 6mm drill bit.

When you are through the floor, use a whole saw to cut a hole to suit your X brace, I just picked the closest I had on hand, not sure of the size.

When you have everything drilled out, you need to drill through the 6mm boot hole with a 12mm drill bit.

When you have this done on both sides, you can remove the top strut nuts, slide the X brace into place, put the bolts through the floor and bolt it all up.

Reinstall the strut nuts.

I already had the strut plates so I just put them in on top of the brace.

With just the brace installed, and no true rears, you can feel that the car is stiffer at the back. Even if you don’t want to install true rears, this is a great improvement to handling.