Newbie - Home Made Brake Ducts


#1

I’ve been doing track days and slowly building my car towards a SpecE30 legal car. I fabbed these up today with the help of a friend who can weld… I attempted to maximize the airflow to the center of the rotors and not onto the rotor face, but it’s rather difficult to fit a 3in tube into that small of a space.

Comments/criticisms?










#2

Why are they tapered? You are allowed 3". A reduction in circumference means increase in pressure and decrease in volume. Volume is what u need as volume displaces more heat than pressure over the whole surface (unless you are pulling a vacuum, which would be quite impressive). Pressure is provided by speed anyways. Check the bmw sites like Bimmerworld, Harrison and guten for inspiration. Also because the connector is so long, it will move the duct more when u turn. However +1 for DIY!


#3

They are tapered because you can only fit so much between the abs sensor gear and the rotor. If you look at most other solutions, they just weld the tube onto the flat piece and leave it partially obstructed. They could be shortened up, they’re made out of aluminum so they’re pretty easy to cut. I haven’t had a chance yet but I need to make sure they don’t interfere with the shock when turned.


#4

Looks to me like you have plenty of room there though. Also it looks like you have extended bolts and have them up against a second towards the rotor. Be careful of the clearance of the rotor. If you get any movement it looks like the rotor will scrape that bolt or even the plate itself if it flexes. They don’t really need to be that close to the rotor. You could just use the original bolts which would let you skip the tapering. Be careful too of the angle of the tubing rubbing the tire in turns.


#5

Those look pretty good! The clearance between the rotor and your mounting bolt looks pretty tight. When I was doing my cooling set up it was nearly impossible to find ducting that directed the airflow into the rotor hat. I did however stumble across Mason Engineering’s set which is very well done IMO. They are 2.5" diameter which makes it slightly easier to direct into the rotor hat. I have never had a problem with overheating or a mushy pedal. They provide plenty of cooling. Here’s some pictures of my setup for reference.




#6

Nice! After making my own set, I finally understand why yours are shape the way they are. I think if I could make something like those, except in 2 pieces so you don’t have to remove the hub, that would be ideal.


#7

Yea, if I wasn’t already replacing the hubs/bearings I would have just taken the angle grinder to those so they would just slip behind the hub/bearing assembly. Wish I had done it anyways in case I ever need to remove them! :silly:


#8

I was thinking about getting this cheaper hose as opposed to the orange one. Do you think this’ll have any issues melting as its only rated for 300*?

http://www.amazon.com/gp/product/B006K8KCD6/ref=ox_sc_act_title_1?ie=UTF8&psc=1&smid=ATVPDKIKX0DER


#9

You should be just fine with that stuff.


#10

I have always used this stuff and never had to replace it. Been on my current car for over 7 years of racing.

http://www.amazon.com/Garage-Exhaust-Flare-Lok-Rubber-Length/dp/B0053I8THU