Heat buildup causes all sorts of issues in a race car. For the brakes it increases the wear of rotors and pads. It also causes brake fade which is a reduction in braking coefficient all as a result of overheating. So far all the brake cooling kits I’ve seen seem a little expensive running to a few hundred dollars. Especially those manufactured in the USA from the likes of AAF, Turner Motorsport & Hard Motorsport never mind the shipping and import costs.
AAF Racing in the US do this special kit for the non-M e46 however it’s $480 plus shipping (about $60) and import taxes (25% of the total). So $675, about £503 at today’s exchange rate of 1.34$/£. Absolutely no way I’m spending that on some plastic pipes!! I reckon I can do it myself for about £300. (It turned out to be £308) and looks every bit as professional.
Corvette C6
What they’re not telling you is that they use the C6 Corvette brake cooling ducts as the basis. There are plenty of kits for the M3 but very few for the non-M3 variants. I’m going to try and make my own. The two elements that make this possible are the Aluminium backing plates from Burkhart Engineering in Germany and the Corvette plastic ducts available from any GM parts supplier.
These backing plates for 63mm (2.5″) hose are e46 non-M specific from Burkhart Engineering in Germany for £155 delivered. They also include a mounting kit with bolts for fitting it to the 3 original backing plate locations.
It just so happens that the Corvette outlet is also 2.5″ (63mm) and the hose to the backing plates is also 63mm. This should work out perfectly.
The Corvette Z06 (2005-2013) used an ingenious front brake duct which thins out within the wheel well to allow enough clearance for the wheel on full lock. I’m hoping that this will prevent the usual ‘snake’ of tubing that seems to inhabit the other kits that I’ve seen.
The inlet diameter of this duct is 4 1/4″ (108mm). The outlet diameter of this duct is 2 1/2″ (63mm). The overall length of this duct is 21″.
After searching around it was just as easy to import them directly from the US. It seems European outlets charge a premium. Cultrag performance in the US sell these as a pair including UK delivery and import charges for $110 (£86). Or visit their eBay shop.
(GM part numbers are 15829067 (left) and 15829066)
31cm per side was needed of this 63mm (2 1/2″) flexible silicone air ducting so 1m was ordered off eBay for £15.
The outlet flange of the Corvette ducting is a little short for my liking and wouldn’t support the hose clamp sufficiently. One straight tube can be cut in two and one used for each side. In the end I used 45mm of tube on each side. This 63mm outside diameter aluminium pipe is perfect (far left in the picture) since it has ‘rolled bead’ to help with pipe attachment. (£11 off eBay). It worked wonderfully and looked really professional.
Finally 4 stainless steel clips are required for the tubing in the wheel well. (52mm to 76mm clips £5 off eBay)
Despite having 15mm wheel spacers I found out that ‘steering lock reducers’ were still needed to prevent rubbing the air ducts. I’m running 235/40R17 tyres. If you still find rubbing for your setup then either increase the clearance using a larger wheel spacer. They’re fitted on the steering rack and limit the angle there rather than limiting the travel elsewhere. Available from Hack Engineering for £36 delivered.