Front brake duct cooling system is kinda aero related so here it is!
The Baer brakes are large by huge 14" rotors with 6 piston calipers. The rotors are the curved vane type which are designed to move air from the rotor hat through the hollow vanes in the rotor to cool the rotor as long as it's turning. I want to have additional cooling ducts ta aid cooling for several reasons.
A. The aero changes I'm making will reduce the air exchange in the wheel wells. So that might contribute to the rotors, pads and calipers heating more than without the aero changes.
B. I'm running 285 front tires on 18" X 10" wheels that just barely clear the calipers. So the calipers and rotors are kind of shrouded by the wheels which might reduce cooling.
C. With the Yokohama AO 48 DOT R sticky tires I can brake harder during threshold braking before lock up than I would be able to with higher tread wear tires so more heat is generated.
D. Keeping the rotors and pads cooler should extend their life.
E The car is is stock bodied with no lightweight fiberglass or carbon fiber and propelled by an iron headed Pontiac engine so at 3500 lbs + it's no featherweight race car, yet I'll treat it like one on track.
Here's the basics of what I've done.
1. Remove the speed sensor mount to open up more space for a 3" brake duct hose.
2. Make backing plate for the rotor hat that has minimal clearance with a tube to attach the hose.
3. To attach the backing plate I used a threaded boss in the spindle (supplied by Baer with their package) and drilled then tapped two bolt holes in the caliper abutment so the backing plate has three bolts holding it.
4. Modified a couple dashboard vent ducts from mid 80's GM trucks so the 3" brake duct hose would fit on them. They're slightly too big for the duct hose stock so a few V cuts and they can be squeezed just enough to get the hoses on.
5. Mounted the duct opening vents in the core support up high right next to the radiator on each side. This is a high pressure area behind the grills which isn't affected by the bow wave at the very front of the bumper or air dam. I'd originally planned on using the park/turn signal openings however a discussion with Ron Sutton about the bow wave influence and the reduction of pressure on the splitter just below the signal opening caused me to change plans.
6. I've built everything using 3" 300 degree brake duct tubing. It's a tight fit by the outer tie rods and sway bar ends snaking a 3" tube in there with such wide wheels/tires. I checked turning radius, suspension travel considerations, and such but I may find that I need to downsize to 2" tubing. So I'm going to test with the 3" and if all's good make a prettier set of backing plates welded instead of riveted. If there's clearance issues I'll move down to 2" ducts and add inline fans.
Here's the pics!
Spindle with speed sensor mount in pic below.
Speed sensor mount removed (but opposite spindle).
White line in pic below shows how much of the rotor hat is blocked by spindle arms, caliper brackets, and abutments.