Lets Talk About Brake Ducting

Maisonvi

Grass-Roots Vendor
Tracked the car this last Monday with my fancy new Wilwood brakes. Things got hot up front (600+ degrees on the rotor even after 1/2 a lap of cool down)

So Ive decided I need brake ducting. Has anyone done this?

Ive gotten a solid start I think. Ive removed the dust shield and made a template out of cardboard, and then lexan so I can see where I want the hose to go. Next up is selecting a hose size and getting my front bumper off to figure out how to connect to the fog light housing. Im thinking I will 3D print some plenums that mount there.

If anyone has done this, how did you go about it? What size hose did you select and why? Anyone ever use a generic ducting plenum with decent results?20160914_210648.jpg 20160915_192252.jpg
 
Nice work, jealous you have a 3D printer or even access to one

I'm looking forward in seeing how this pans out.
 
Tomas has a few posts on the other forum about the brake ducts he made for his gen1. I'll see if I can find them.

Yeah Im going through them now. There isnt much on there about how he chose what he chose. Or any real data on what the difference with and without was
 
Took some other pics last night (sorry they suck, didnt realize it at the time)

Trying to figure out where to route the hose. Looks like I will only really be able to fit 2" tube. Maybe two of them if I can figure out some sort of "Y" connector.

First pic is of the easiest place to mount it. Should be able to just mount it straight on and run it down under to the fog light housing.20160915_192639.jpg

Second spot I might be able to run it under the 1/2 shaft, but I worry about it hitting. I jacked the arm up and down and it seems to clean in the whole range, but its close. This again is at the 2" size.

20160915_192626.jpg
20160915_192621.jpg
 
I am running a Powerbrake BBK with 340x34 rotors, no need at the moment to run brake ducting but 2" ducting should work, just make sure to direct the air in the center of the rotor or as close to the center as you can get.

Thats the plan. I think Im going to start with a 2" duct, but make provisions for two 2" spots. Both as close to the center as possible.

if I have to I will create a T and make a 3" to 2" connection.
 
600°F isn't terribly hot.

That said, it shouldn't hurt to add some ducting, but as Rafal said you want to make sure it's being directed as centrally as possibly to promote even cooling.
 
600°F isn't terribly hot.

That said, it shouldn't hurt to add some ducting, but as Rafal said you want to make sure it's being directed as centrally as possibly to promote even cooling.

600 was after only about 5 minutes of track time and 1/2 a cool down lap, plus driving back to the pits. So I assume after 20 min of pushing them, I could at least double it.
 
Yeah... As I'm sure you know, the caliper temp is probably more important as a data point, as that is what is directly transferring heat to the fluid.

You might want to look into some temperature-indicating paint for your rotors and maybe some stick-on temp strips for the calipers, as those will both give you much more useful information about the PEAK temperatures you're reaching while out in a session.
 
I stumbled on this while surfing around Mazdamotorsports.com earlier today. Although the fog light bezel shown appears to be for the Miata it shouldn't be difficult to create a duct from fiberglass or form something from ABS.
Brake Duct Kits for Gen2 Mazdspeed 3 & MX-5 (BTW, not cheap at near $600 for the MS3)

If you'll end up with flat dust shields these might make one less part to fab. Although steel would make for a more durable dust shield I've had good luck using these flanges from Aircraft Spruce for various aircraft and non-aircraft projects.
Aluminum Flanges for Ducting

Here's a nice radiused 2" intake but may only be able to fit the Pu sized fog light area with some work.
SCAT TUBE INLET

SCAT tubing makes for nice duct work that's flexible, won't melt or catch fire and is cheap. Don't underestimate Aircraft Spruce, Chief and others that cater to the experimental aircraft crowd as their prices are often far better than Pegasus and other racing equipment suppliers.
 
Due to package restraints (mostly axles) I'd recommend the bottom location and going under the LCA with the hose.
 
I stumbled on this while surfing around Mazdamotorsports.com earlier today. Although the fog light bezel shown appears to be for the Miata it shouldn't be difficult to create a duct from fiberglass or form something from ABS.
Brake Duct Kits for Gen2 Mazdspeed 3 & MX-5 (BTW, not cheap at near $600 for the MS3)

If you'll end up with flat dust shields these might make one less part to fab. Although steel would make for a more durable dust shield I've had good luck using these flanges from Aircraft Spruce for various aircraft and non-aircraft projects.
Aluminum Flanges for Ducting

Here's a nice radiused 2" intake but may only be able to fit the Pu sized fog light area with some work.
SCAT TUBE INLET

SCAT tubing makes for nice duct work that's flexible, won't melt or catch fire and is cheap. Don't underestimate Aircraft Spruce, Chief and others that cater to the experimental aircraft crowd as their prices are often far better than Pegasus and other racing equipment suppliers.

Of course they dont have Gen 1 parts, not that at that price I could afford to do that. My plan right now is to pull the bumper and see what the lights look like and how I can make something to replace them. I have access to a 3d printer that might serve for this pretty well.

Aircraft spruce is a great site, never thought to look there for this type of stuff. Ive bought things from there plenty of times before, so I will see what they have.

Ive found a few places for ducting. Right now Im going to work on the dust shield replacements (my plan is to just weld a tube on for the hose connection). Then I will get to the bumper. This might become a winter project the more I look at it. Just dont have the time right now to do it all.
 
Of course they dont have Gen 1 parts, not that at that price I could afford to do that. My plan right now is to pull the bumper and see what the lights look like and how I can make something to replace them. I have access to a 3d printer that might serve for this pretty well.

Aircraft spruce is a great site, never thought to look there for this type of stuff. Ive bought things from there plenty of times before, so I will see what they have.

Ive found a few places for ducting. Right now Im going to work on the dust shield replacements (my plan is to just weld a tube on for the hose connection). Then I will get to the bumper. This might become a winter project the more I look at it. Just dont have the time right now to do it all.

High price aside there is a constantly thinning list of Gen 2 parts as well.

There are others like it out there that cater to the experimental crowd so search around you might be able to find others with different stuff.

The disc shroud in the pic on Mazdamotorsports for the Miata does provide a good pictorial of directing the air towards the center of the hub as @Code Monkey and @Nliiitend1 noted to help with more even cooling. Most of the ones I've come across are rather thin sheet metal and easy to roll a bead into to help retain the duct with the clamp. It can also be thin enough to roll your own tube.

I could certainly see the project taking more than a couple Saturday's for both the fog light light duct and disc shroud. Stuff like that almost never is quick and easy to get them right.
 
High price aside there is a constantly thinning list of Gen 2 parts as well.

There are others like it out there that cater to the experimental crowd so search around you might be able to find others with different stuff.

The disc shroud in the pic on Mazdamotorsports for the Miata does provide a good pictorial of directing the air towards the center of the hub as @Code Monkey and @Nliiitend1 noted to help with more even cooling. Most of the ones I've come across are rather thin sheet metal and easy to roll a bead into to help retain the duct with the clamp. It can also be thin enough to roll your own tube.

I could certainly see the project taking more than a couple Saturday's for both the fog light light duct and disc shroud. Stuff like that almost never is quick and easy to get them right.


yeah it will be an experiment for sure. I will try a few things, but the stainless Im using for the dust shield will be decently thick, without being overly heavy. I can always add reinforcement if I feel its needed. Getting those done are first priority.

I think I can run a 2" duct under the half shaft, but over the LCA if I make a mount so that it wont move. Played with the steering and compressing the suspension and it seems to have worked out. That would put the duct super close to the center of the rotor with the whole opening inside of the actual rotor.
 
@Maisonvi

Fantastic thread. I'm more than happy to contribute 3d printed prototypes, measurement mock ups, etc.
I also have a spare set of brake shields, a welder and some sheet metal.

My 3 may not need it right now, but the racecar 6 definitely does. 3 & 6 rotors are very similar, except that the 6 is further offset from the hub face. @xfeejayx

I also have a bunch of tubing designed for brake ducts around.


Good ideas and Inspiration from the evo world:
Album including 3d printed protoype-
http://s132.photobucket.com/user/jid2/media/103_1384.jpg.html
103_1384.jpg
 
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