I finally got around to installing the brake ducts and hoses that I bought last summer. For the most part, the switch to Wilwood calipers and ducting into the wheel well solved my brake temperature problems during short track sessions of 25-30 minutes. But for longer sessions of 45-60 minutes or more, especially during hot, humid days, I was still having heat management issues. Oddly enough, not with the rotor or caliper, but with the ABS sensor in the carrier, which would turn off ABS mid-session.
The brackets I used came from Sneed’s Speed Shop and the hose is from Pegasus Racing. Chris Sneed makes a nice bracket that mounts behind the foglight opening of the R53 MINI, as well as a bracket that bolts into the dust shield mounts. The bracket to the bumper attaches via a couple of pop rivets. Aerodynamically, it’s not the ideal location, but the front of the MINI is fairly flat so I think it will work well enough. The highest pressure area is closer to the center of the bumper, but I didn’t feel like fabricating a bracket that worked around the radiator mount. I’m also using a 3 inch silicon hose attached behind a 2.5 inch opening in the bumper. I’m sure that’s not ideal, but since the hose is ribbed, I figure what I loose in turbulence is made up for in volume. (Sounds plausible at least.)
Installation is fairly straight forward. You want the straightest possible routing for the hose that doesn’t pinch or rub against other moving bits (like the crank pulley, axle or serpentine belt.) You have to cut away a fairly substantial chunk of the front panel to create a path to run the hose behind the wheel well liner. (Try to save the tab to mount the liner.) Use Zip Ties to keep the hose tight against the frame rail. Be sure the hose is long enough for full travel of the steering. Also be sure to leave enough hose to facilitate mounting of the bumper cover.
You do have to remove the brake caliper and the rotor to mount the bracket to the carrier. Sneed’s brackets are designed for stock rotors (stock Cooper S or JCW). If you are using an aftermarket caliper and rotor like the Wilwood’s I used, you may have to make some adjustments to get the to fit without binding. In my case, it just took a little persuasion (with a hammer) to get the brackets clear of the rotors.
Update #1: When I pulled the liner to check the brake hose after a couple of months, I found out it was getting pinched between the liner and the crank pulley, so I wrapped it in an aluminum sleeve.
Update #2: After a weekend of hard driving on the track with PCA Potomac at Summit Point, I found that I crushed the duct between the axle and subframe. The exposed wire shredded the CV boot. Trying another sleeve, but may have to go to smaller diameter hose. Will see how this holds up at the Shenandoah Circuit in a couple of weeks.
See Part Three here.