Re: Sean H. - your brake ducts..question (archive)

Thanks! Let's see if I can answer your questions (I'm by no means a mechanical wizard).

- looks like the install is to basically cut the lower lip off the chin spoiler, then fit the ducts in. Other than the cut for the duct pick up and the related mounting tab, is there any other cutting? Also, I know you had a mechanic do it (body shop?)...can you estimate how "exact" the cutting has to be? Do you know what tool was used to make the cut? Is there an outter lip on the duct that allows for minor inperfections? Trying to get a feel if this is something I would like to tackle or not.
That pretty much sums up the amount of cutting that needs to be. Just a notch on the side and then trimming out the lip on the front. There is a bit of overlap with the channel, so you don't have to be exact, but I would be careful. The mechanic isn't a body shop guy, but is good at this sort of thing (he's done the same of type of things for my brother) used what amounts to a jigsaw to make the cuts. He went at by cutting a little, looking to see if it was enough to fit, and then trimming away again. He just repeated this measure-trim-measure process until he got a good fit.

- Can you describe where the ducts channel the air? Is it to the front of the rotor (leading edge)? Or do they somehow get air near/under the center hat of the rotor? What is your opinion on the "volume" of air they might be able to direct? Bascially, I'm interested in what you think their cooling effectiveness might be...

The ducts cover a pretty good swath of the rotor, directing air towards the front edge and the back. The duct is connected to the fender well at the bend (if that makes sense). It does a good job of keeping cool air on the rotors, but it's no where near as effective as one of the kits that "shrouds" the rotor and blows cold air directly on it. After boiling the fluid and locking a caliper at my last driver's school, I'm looking to everything I can to keep them cool. I just feel that every little bit will help.
I hope this helped you out some. If you have any more questions I'll try my best to answer them.
Sean H
'92 535i

Follow Ups:

Addendum Sean H 20:29 10/07/2001 (3)
- The ducts are usually designed to duct the air Bill R. 20:35 10/07/2001 (2)
  - thanks...more Jeff N. 20:56 10/07/2001 (1)
    - Here you go Jeff, Bill R. 21:13 10/07/2001 (0)

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