Cheap DIY Brake Ducts

[1MOREMOD]

okay thanks. im jumping over here from the other thread. just been climbing around under the car for a few to get a feel for it. im worried no matter where i come out the backside of the tray im gonna be rubbing when wheels are turned in towards the tubing since i was planning on running all the way to the backing plate. not really sure how this is gonna work.

[adc]

Originally Posted by chriszeh

okay thanks. im jumping over here from the other thread. just been climbing around under the car for a few to get a feel for it. im worried no matter where i come out the backside of the tray im gonna be rubbing when wheels are turned in towards the tubing since i was planning on running all the way to the backing plate. not really sure how this is gonna work.

I hear you. It was one of the reasons I picked a smaller diameter flange/duct combination (2.5").

I've been thinking about this and if I could engineer the exit hole to be rectangular, and a set of removable rectangular (and flat-ish) ducts to come out of them, then the clearance problem may be fixed because flat rectangular ducts would hug the inside of the fender liner really close and should give sufficient wheel clearance.

But in the meantime I figured that even the "firehose" approach, of directing the outflow towards the brake area and hoping for the best, would still be better than nothing. Most older BMW's used this approach...

All I can say is that with Pagid yellow (RS-19) pads and these ducts, I've been ok on track for the past year. Real thing or placebo, the mission was accomplished.

[1MOREMOD]

i plan on waiting now until mid winter to do the install until after my dealer replaces the rotors under warranty. im ready to do it but makes no sense when i wont be on the track. i may add an extra clamp to the fender liner in an attempt to create as much space as possible. if i have to squeeze the tubing in one spot to make clearance i guess thats what i have to do. what do you think of coming out at the corner area created on the tray right at the bottom of the fender liner so it would be below the spot that the tire naturally wants to touch when at full lock. it would mean going through the spot where the fender liner retainer bolt is furthest toward the center line and closest to the bottom?

[1MOREMOD]

https://skydrive.live.com/?cid=a81a2...2%212938&sff=1

this is the link to cantrells set up, i think. they use custom backing plates and i will try to replicate with my system. dont like the entry point on the bumper but will fix that with the gt4 ducts.

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Originally Posted by chriszeh

https://skydrive.live.com/?cid=a81a2...2%212938&sff=1

this is the link to cantrells set up, i think. they use custom backing plates and i will try to replicate with my system. dont like the entry point on the bumper but will fix that with the gt4 ducts.

For some reason I cannot see the link.

In terms of clearance - what wheel setup are you planning on running at the track? The front can take a more aggressive offset - if using stock wheels, perhaps a 10-12mm spacer all around for track use would give you the needed clearance, also considering that on track you probably won't have full steering lock (if you behave ).

I would never use a full duct with backing plate for street driving.

[1MOREMOD]

i have vmr v710s in 19/9.5 et22 with no spacer and advan ad08s 265/30. why no ducts on the street. it seems like a pain to install and remove for each track day.

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Originally Posted by chriszeh

i have vmr v710s in 19/9.5 et22 with no spacer and advan ad08s 265/30. why no ducts on the street. it seems like a pain to install and remove for each track day.

Summer would probably be ok, but winter I don't think you could get the pads (especially aggressive ones) to good operating temp with full ducts. No street car has anything like this.

What people do is ensure the "middle" connecting duct can be removed/installed - the piece sitting inside the wheel well. That implies putting a flange in the fender liner (the backing plate already has one).

[1MOREMOD]

is there a double sided flange so you can mount to the inside of the fender well with one clamp and the outside with the other? this is getting more involved. i just ordered an extra set of 3 inch flanges so i have a set for the inner fender well and 1 for the backing plate. will fab something so its 2 parts. for winter removal.

[adc]

Originally Posted by chriszeh

is there a double sided flange so you can mount to the inside of the fender well with one clamp and the outside with the other?

I think you can make something by putting 2 of them back to back - one on each side of the fender liner.

I bought mine from these guys: http://www.aircraftspruce.com/catalo...uctflanges.php

[Kunman]

nice, doing this soon.

[adc]

You want my parts?

I decided not to put them in anymore after I had an - ahem - agricultural excursion this past winter, and the insurance company replaced the undertray with a new one.

I have the ducting, flanges, clamps, etc everything you would need except fasteners.