BRAKE COOLING 101
SICK OF COOKING YOUR BRAKES AT TRACK DAYS? A SET OF LOW-BUCK BRAKE COOLERS MIGHT JUST BE THE ANSWER. LEARN THE INS AND OUTS, AS WE SHOW YOU WHAT YOU NEED TO MAKE YOUR OWN
These tech guides aim to arm you with the necessary info and knowledge to get out there and give it a go yourself — with no professionals needed and a price tag that won’t break the bank. This month, we delve into brake ducting, a cheap and simple solution to that enemy of any weekend warrior, brake fade, one of the scariest things that can happen when you’re committed coming into a corner. Brake fade is caused by overheated brake rotors transferring heat into the caliper and, in turn, overheating your pads — to the point that they disintegrate — and boiling your brake fluid. Assuming your car has vented rotors (if not, this should be your first upgrade), the rotor will be designed to pull air from the centre outwards. So, ducting cool air to the centre back of the hub is a great way to reduce brake-rotor temps, and this will have roll on benefits for your pads and fluid. Each car is going to be different, both in terms of the place where you collect air from and the place where the duct attaches to your brakes. But the theory remains the same: duct cool air from the front bumper to the centre back of your rotor. If you have a modern popular chassis for modifying, you might be able to purchase a complete off-the-shelf kit, although putting together a kit is a pretty easy option if you have a few basic skills and tools. We should mention that swapping to a higher grade rotor, pad, and fluid is also a good idea to reduce the effects of overheated brakes, but adding cool air is going to help if you have a heavy vehicle or are heavy on the centre pedal.
1 COLLECTING COOL AIR
Choosing a location to pick air up from will depend on your car and what, if any, kit you have on it. Most modern cars have intakes on the side of the front bumper, while some kits have them on the side of the centre opening (see left). You can also purchase fibre-reinforced plastic (FRP) ducts to fix to the back of the bumper to which your ducting hose will attach. If you’re running something a little older, like this Mazda 616 (see right), you will need to make something. This particular car uses a Ford Escort front-splitter purchased locally and modified to fit the lower valance shape. The circular ducts are alloy tubing with small tabs welded to the back that we then glassed onto the splitter. Simple, cheap, and effective. Another option, if you don’t want a modified bumper, is to have the duct sitting at the bottom edge of the bumper so that air travelling under the bumper will be collected.
2 FEEDING THE ROTOR
On the back of your rotor, you will want to feed the air to the centre of the rotor, so that it will draw this air through its veins and out the outside edge. Anything like the two-piece rotor pictured is directional. There are a few different ways to attach the exit vent — the method you use can be as basic as to cable tie the hose to your strut, although this is not a very efficient way to do things. We recommend either a small bracket that bolts to the caliper mount through the
caliper bolts and holds the three-inch alloy pipe with a direction vent pointed to the inside of the rotor. Doing it this way ensured that the air would be forced to go where we wanted it. An alternative would be either to attach the exit vent to the backing plate that most rotors have from factory or to remake the backing plate with the duct built-in — this option would ensure more of the rotor would get fed cool air; it’s this style that’s employed by most high-end race machines.