brake cooling ducts?
 

Ok, I did a search, and couldn't find anything about brake ducts for a 2G GXL. I know Mazda Competition sells them, but I wanted to know if anyone has fabricated them. From looking at pics of other car's applications, it looks like it would be a metal plate, with a ~3" metal pipe welded to it, for a flexible hose to attach to. Seems pretty easy. I know my car has the ducts that are supposed to cool the brakes, but they can always use some extra cooling. I was thinking I'd cut out where the stock ducts are, and run the flexible hose through there.

One thing I was wondering about, though...how do you keep the hose from rubbing on the wheels/tires/brakes when the wheel is turned? Would this be OK for daily driving as well as track use? Any pics you guys could take would help a whole lot!


Thanks,
Stephen

Did you check Mazda Motorsports, that is where my first gen ducts were purchased.

yeah, they sell them, but they're $150 for a pair...that's a little pricey

This is one of my projects for the coming months.

My plan is to use the stock front brake duct piece (the one at the front of the bumper, right at the duct inlet) and combine that with a generic 6" x 9" air inlet duct with a 3" outlet. Then I'll run my hose through the wheel well (have to find a place to cut), and attach it to - here comes the fun part - the Mazda Motorsports ducts. That is, unless somebody else comes up with something better (read - cheaper) before then.

Note that I've also taken out my fog lights. The stock fog lights block any useful portion of that front brake duct piece.

As far as keeping the hose from rubbing, it's just a matter of positioning and checking to see that the hose isn't rubbing at the limits of steering travel and suspension travel. Once you find a position where it won't rub, you're good to go.

Edit - I guess that database repair an hour ago was to clean up some junk. My posts have seemed to drop a bit.

What about running the hose to the front bumper in front of the radiator? Seems like that would work just as well...

It would, but then you're blocking air from going to your radiator, not much, but it's still something. Our cars have a separate duct that can go to the brakes, why not use it?

ditto, do you really need the fog lights? however, if you are overheating your brakes in autox then you have some real brake issues that need to be solved.

I like the fog lights...also, I overheat the brakes on the street...bad place for them to go.

Stephen

I made my own. I'm with SLINGES. Mazdacomp gets way too much for their part. Made mine out of 1/8" sheet aluminum backing plate and then some thin (forget the gauge) sheet formed in the shape of a tube that was then riveted to the backing plate. It's attached with the bolts that hold the stock dust shield in place.

This is a pretty bad pick but it's all i have right now. I have a better one but I'll have to look.
http://community.webshots.com/photo/...7327rWNfVuaXcg

If you guys want to wait about two months I could fab some for you. I'm in the process of relocating now and it'll be a while before I'm up and running. Price would probably be in the $75 neighborhood.

This is the easiest way to do the ducts in the front.
http://community.webshots.com/photo/...47942059GmYIUE
The S4s didn't have the fog lights so it's an easy choice for us. I used commercial plastic ducts riveted to the front fascia and then attached the hose to those. It makes for a smoother entry for the air, is an easy and secure way to attach the hoses, and looks cool.

The hoses will almost have to be routed in an area where they WILL get smashed. With my car you basically have to tell yourself not to turn it to full lock. There's just no way around it. I've thought about laying up some ductwork in carbon fiber or fiberglass that would be low profile to run behind the tires and take more abuse than the hose. But it's still a ways off.

Finally, there is no way you should be cooking your brakes on the street and if you are you need more than cooling ducts. Start by flushing the fluid and using a good DOT4.

Chris

That looks pretty cool. I was thinking earlier today about simply attaching the hose to the stock dust shield...what do you guys think about that?

BTW - The last time I drove my car hard was in the fall, and since then I have flushed out my brake fluid and installed much better pads, so hopefully I won't be cooking them as easily now, although I do live in an area with a lot of hills and sharp turns, so I still give my brakes quite a bit of abuse, so I figure if I can do the ducts cheaply, it wouldn't hurt.

What'd you flush with? I use Motul 600, no ducts, repeated hard stops on track, no fade with Carbotech Panther Plus pads.

Adding the ducts to the stock dustshield probably would work ok, just try to get the air moving at the center of the rotor disc, not the braking surface.

PaulC

Ludwig that looks kinda odd having the hose come soo close to the actual rotor is that the way you have to do it? Take into concideration im a newb. :D

For now, I'm using generic DOT-3 (the best that wal-mart had) and Hawk HP+ pads on the front. I'll be upgrading to ATE SuperBlue whenever I get the chance, though.

slings, i said autox not street.

chris i have to disagree on the street thing. i have done it once. i was bombing a backroad in the camry with a 200lb passenger and a tool box. it was a wrc type backroad (my first time catching air on asphalt, and at 50-70mph). needless to say on arriving at the junkyard to pick up my tranny, i almost didn't make the lot. pedal just went to the floor. probably the only camry that has smoked out of the front wheels due to overheated brakes. however this was 15-20min of highspeed, non-stop, very hilly, twisty road and a camry's brakes weren't really designed for sport.

Shortbusriot,

It's key that all the air is directed at the rotor, so naturally, you want it central to the center of the rotor.. Why the center? The rotor is vented inside, air hitting only one side of a rotor will cause uneven cooling, and possibly warp a rotor. Directing it into the center, that air is then vented through both sides of the rotor, and doubles your effective cooling surface, as well as provides even cooling for the whole rotor.

Also remember that there's a lot of air moving around the wheel, you want it close to keep the ducted air going where you need it most.

slinges,

Get rid of that fluid ASAP, look into Ford HD DOT3, Motul 600 or some Castrol ATE Blue. More than likely the fluid is boiling.

PaulC

cool, I'll definately swap out the fluid next time i'm home...is there a procedure for getting all the old fluid out? When I changed it last I just bled all the brake lines until no more fluid came out, then I put the new fluid in.

I'll probably do the brake ducts anyway since I'm always looking for inexpensive projects for my car :)

thats exactly what i was talking about in a post from maybe a week ago. the uneven cooling of the rotor with those brackets you can buy.

anyways..... about the duct rubbing the wheel. heres how its done on the race car. we used aluminum ducts which expand and bend very easily. then we bent the ducts at one point from the circular shape, to an oval shape against the inside of the fender well to clear the tire. it still rubs a LITTLE bit, but not enought to effect it. does this restrict the air flow a little bit? not much if at all. could aluminum damage the tire? i doubt it, hasnt happened yet.

by the way.... the rubbing on those ducts isnt happening on the track ya know.

Good advice Paul.

If ya want the cheap and dirty approach find a soup can the same size as your hose and either rivet or braze it to the stock dust shield.

And Jeremy what type of fluid did ya have in the Toy when ya boiled it? Fresh?

Chris

flushing brake fluid:

Use an OLD turkey baster to remove as much fluid from the reseviour as you can. add fluid till full. Open the Pass Rear brake fitting, and pump away until you see fresh clean fluid. It will be noticibly cleaner/clearer.

repeat for every corner of the car.

DON'T let the resevior go dry.. Always make sure that thing is as close to full as you do this, you don't want to have to bench bleed your master cylinder after it's all done :\

PaulC