Hopefully not long cause Hawk Blues + stock calipers + stock rotors = brake fade for me. I need to get those puppies some airflow.

 

Yep - since I posted I see that BMP makes a brake duct kit for BMW's with a new backing plate click http://www.bmpdesign.com/product-exe...earch_model/56

SInce they also have alot of nice MINI stuff, I emailed asking when/if they are working on a MINI version... I'll post what I can find out...

Derek

 

I took some pic's of how to trim the ducts today. I kind of tore up the right front one last Sat at a test and tune event. The parking lot is a little rough with a few places where I bottomed out pretty hard! Not a surprise. We got in 20 runs with just 1/2 hour track duty. What a great event. Something was bound to give though.

I was in a hurry when I did the trimming. Trim the bottom flush, leaving a little radius on the bottom. then put it against the air dam to get an idea how high to start the cut. I could have left about an extra half inch on one side. No problem. A little ducttape fixed it up! I used a hacksaw to cut the vertical cuts in the dam and a razor knife to cut the top. If you're careful the removed pieces can be put back at some later date! I used 4 SS #10 1/2 screws to hold the duct in.

Now that I tore one side off, I'm going to make some backing plates out of 3/4 x 3/32 aluminum from Home Depot.

 

Here is some food for thought....

I'm trying to help a Fox body Mustang customer with some duct issues as well. We did some note comparing and found that this car (like the SRT4 upon some investigating) has a problem with the fog lamp holes being the inlet.

In much the same manner that the ducts here shown may exhibit. Actually more here when thinking about it more...

'Cup cars have found that ducts placed too far to the outer edge of the bumper cover don't flow well. As speed is increased the air spills over the hole at such a rate that it does not enter the hole. Thus it's not a high pressure zone. This was confirmed with some poking around at the front covers of cars at the Glen. Air from the middle nearst the radiator is the spot to be in. Seems the SRT4 suffers this same issue.

Ducts shown in the first pic will have the same problem. You're in a low pressure zone below the chin spoiler or splitter. As the air dams up in that bend it washes up into the rad and rolls off the edges (in theory) producing down force on the nose. What washes under it is going to be very turbulant at best.

The place for those parts is in the chin spoiler area or the rad opening. Not under it.

Not being critical here, but the above work has turned on the light a bit more on placement. I'm no aerodynamicist (hell, I can't spell it!) but I do believe I'm correct on this for the MINI as well.

 

No matter what you do for DUCTS you must remove the dust shields first!!!

I did that just befor going to a track (SLMP) and was amazed at the fact that the center hole in the shields is (mostly) covered by the steering spindle. Only a couple of little spots are open to allow air to flow into the inside of the brake disk thru the center hole of the dust shield.

 

All,

Posted my latest winter project on another NAM forum before Greg, aka onasled, told me that there was an active thread on brake ducts on this forum.

Here are a couple of photos of the passenger side air duct installation. Am using 3" ducting for the sake of air flow. Adapted a BMW Z-3 wheel shroud for the outlet end and am using the fog light holes in the front bumper at the inlet end. Ducting of this diameter presents major problems for wheel clearance. Have done major plastic surgery to the inner wheel wells to gain wheel clearance. Not for the faint of heart. Would like to come up with a better solution for the dorky intake openings.

The photos are at this URL: https://www.northamericanmotoring.co...955#post743955 posts 361 and 370. Sorry that I don't know how to transfer these photos to this forum.

Regards,
John Petrich in Seattle

 

Me likey!

 

I used some pre made oblong nylon ducts when i did this last year. You might like it better than your present ones. You can get similar ones from any good race shop supply company.

Randy
M7 Tuning

 

onasled- Could you post some photos of your brake ducts as the original posters photos are missing and most of us are looking to cool the center of the rotors.

 

I'll see if I can dig them up.

 

Ok something that I noticed noone her mentioned that I think is a big deal is this. Why has noone tried going through the shroud that is located on the sides of the radiator and installing naca ducts there instead of stealing air off the front nose? We did a lot of testing in our race cars (not MCS's) with this model and found that we were able to get a ton of downforce on the front when placing the brake ducts inside the shroud in the main radiator opening at the lower portion of the car. I would think that we could do the same thing. This would allow for greater front nose grip as well as solving the cooling issue that many are having with the brakes. And I know that some are thinking that this does not make sense because then you are stealing air from the radiator, btu honestly I dont think the radiator is goign to car seeign that the whole front of the car is devoted to that and a ton of air flows into that area. That is where I would see if I could place my brake ducts. Just my $.02 and curiosity.
Thanks

 

...or an NACA duct just in front of each front fender...dunno what this would do to aero, but it would ad length to the path creating a bit more velocity...or less depending on the size of the duct/piping...

 

I'm planning on taking advantage of the fact that I fon't have fogs and run ducts almost straight (yes I know there will be some bending) back to the wheel well. This shouldn't affect my aero much if any, and will take advantage of the positive air press on the lower front of the car.

 

Hey, we could also vent the top of the front fenders...

 

Well yes if you don't mind having everything you drive through kicked up into the engine or removing the wiper resivoirs. I think for venting the best option would be some wheel that allowed flow out along with perhaps a multi duct system, one coolong the rotors and the other to cool lines and lower the ambient temp, preventing boiling of brake fluids.

One thing to keep in mind, as the Corvette engineers and drivers did testing of C6 prototypes at the Ring they found that a smaller duct worked better overall because the small ducts prevent the excessive lift they saw with the larger ducts. The lift caused the handling to suffer dramatically. Just food for thought.