I installed the rear BBK just before Hurricane Sandy hit, so I didn't get a chance to put up the photos until now. We only just got power at my house 2 days ago and power was restored Zeckhausen Racing on Monday. What a nightmare.
Part 2 of the StopTech 4-wheel big brake upgrade on the BMW F30 328i. Front brakes were installed Thursday night (Oct 25) and now (Oct 27) it's time to do the rears. These are 4-piston ST-40 calipers with 345x28mm rotors.
The garage is ready to go - all the leaves swept out.
All my "assistants" have arrived. It's been years since Mike Mario, Doug Holcomb, and Mike Turner have been in my garage at the same time. Feels like the good old days!
The car is up and the wheels off.
Rear brakes are tiny, with 1-piston calipers and drum-in-hat design rotors. That means the parking brake is inside the center portion of the brake rotor. The StopTech upgrade will preserve the parking brake function.
Side-by-side comparison of the original and StopTech rear calipers and rotors.
Time to pull off the stock brakes.
First out is the electronic pad wear sensor. Have to carefully wiggle this thing out with needle nose pliers. If you squeeze too hard, it crumbles and a pad warning appears on the dash.
The brake line is disconnected with an 11mm flare wrench and now the two 16mm bolts holding the caliper have to be removed. There is ZERO room to operate, so I have to use a box end wrench and a hammer to slowly work out the bolts. BMW puts thread locking compound on them, so they fought me every step of the way. Strangely, they did not do this for the front brake caliper bolts.
Caliper is finally off. 6mm rotor retaining screw is removed from the hub and a few strikes of the dead-blow hammer and the rotor comes right off. Make sure the parking brake is released, or else the rotor will not budge.
With the rotor removed, you can see the parking brake mechanism. Two mechanically operated brake shoes push outward against the drum which is built in to the stock rear rotor.
To make room for the larger caliper, we need to snip two triangular chunks from the stock dust shield.
The StopTech rotor is much thicker and will rub on the lip of the dust shield, unless we snip it off. These days, BMW uses really flimsy sheet metal for the dust shields, so it's easy to remove with tin snips. For older BMW models, a high-speed rotary tool is preferred.
Dust shield is all trimmed and the StopTech caliper mounting bracket is installed using the stock brake caliper bolts, torqued to 55 lb-ft.
The StopTech rotor is installed and held in position with the stock 6mm rotor retaining screw. A little bit of Permatex anti-seize is a good idea to make it easier to remove, a couple years from now.
The new 4-piston caliper slips onto the bracket's mounting studs. It's held in place with a pair of 1/2" Jet nuts, torqued to 40-45 lb-ft.
Brake pads drop right in from above. Make sure the proper side faces the rotor! I've had a few customers install these backwards. (No, I promise I won't tell anyone who did this!)
The caliper stiffening bridge is held in place with a pair of 5mm bridge bolts.
The new stainless steel braided brake line is threaded into the caliper body, then connected to the chassis fitting and tightened with an 11mm flare wrench.
The stock BMW pad wear sensor fits right into a slot at the top of the new brake pad.
The brakes are bled and wheels re-installed.
We're all done! Time to button up the car, pick up the tools, and then go celebrate our success.
A relaxing lunch at Panevino Restaurant - the traditional Zeckhausen Racing post-installation hangout. They had our table waiting for us and proper beverages all laid out in advance! Yes, we've been eating here regularly for over 20 years . A great way to celebrate another big brake installation.