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-   -   FD Brake Ducts (https://www.rx7club.com/race-car-tech-103/fd-brake-ducts-250268/)

DigDug 12-10-03 02:13 PM

FD Brake Ducts
 
Anybody running brake ducts on an FD that would like to share some pictures? I am interested to see how people manage to shoehorn them into the FD's fenders...

I can't imagine how I would accomplish the task on my car - I am running 245/45-16 R3S03's, and there is VERY little room to the inside of the wheel when turned to full lock. However, I am certain there must be somebody out there that has figured out the appropriate routing for the hoses...

rotary-tt 12-10-03 02:57 PM

Comp brake ducts? The R1 version comes with a couple of small ducts to direct air to the backing plates but they aren't race ducts. I believe the '99 stock front end also has it's own ducts.

bradrx7 12-10-03 03:38 PM

I have dedicated 3" hose ducted to my backing plates. The backing plates are fabbed from thin sheet aluminum and a fabbed 3"OD tube is welded to the backing plate on the front side. I then route 3" silicon hose from Racers Parts Wholesale from the backing plate to a plastic collector duct under my oil coolers on each side. I use the GTC nose, BTW. Using 265/650x18 slicks there is some rubbing on the hose, so I replace it as needed. I get about 20 track days before needing to replace the hose.

DamonB 12-10-03 05:01 PM

CWR made carbon fiber brake ducts. They were really just scoops positioned inside the inner fender but could easily have a hose(s) connected to the inlets if you're resourceful, but I have never looked close enough at tire clearance. The hose may actually have to come from the engine compartment or belly pan somehow.

http://www.crookedwillow.com/images/...0duct_x241.gif

DamonB 12-10-03 05:02 PM


Originally posted by rotary-tt
Comp brake ducts? The R1 version comes with a couple of small ducts to direct air to the backing plates but they aren't race ducts.
They really don't direct air to the backing plates, they just spill some into the fender area. A closed system with a hose is tremendously better as it will work when the wheels are steered as well and not waste air that entered through the duct in the first place.

DigDug 12-10-03 08:47 PM

The carbon piece looks nice! That is about what I expected to find, actually. I figured somebody had to make a piece like that!

As for the hoses, that is what I was thinking, DamonB - they would probably have to run in from the inner side of the well, probably from underneath. I just worry about the occassional "off" tearing out the hoses...

bradrx7, you run 265/65x18's? Wow, I thought I had clearance issues in the wheelwell! Is your car lowered significantly? Mine is fairly low, and with just 245/45x16's, at full steering lock, my tires are eating away at the well liner in the front, and I have only about an inch and a half between tire tread and the inner-side well liner. That was the source of my concern with the hoses. Of course, the car never sees full steering lock in practice, but I don't want to be rolling out of the paddock into staging and tear out a hose! Do you have any pictures available? I can snap some pics of the clearance in my wheelwells if needed...

DigDug 12-10-03 08:49 PM

And yes, the R1's stock ducts are pretty much worthless. Not to mention that my car has none of that "ducting" left anyways.

BigIslandSevens 12-11-03 12:24 AM

Anyone know the price and availability of those CF ducts. They are very nice. looks like they were supposed to be there.

skunks 12-11-03 05:26 AM


Originally posted by BigIslandSevens
Anyone know the price and availability of those CF ducts. They are very nice. looks like they were supposed to be there.
i could probally make that, it dont look overly complicated

Mahjik 12-11-03 08:15 AM

Hey DigDug,

I looked into the same thing when I had some serious fade on the track back in September. I found the brake ducts at N-Tech:

http://www.ntechengineering.com/inde...d=6&model_id=2

Unforuntately, Nick was out of them and wasn't going to make another production run as he doesn't have the demand for them. Apparently, the ones for the stock brakes are the hardest to make (due to lack of room down there).

When I spoke to Nick, he suggested I use his competition brake pads so I did for my next track session; they worked flawlessly with no fade what so ever. I'm still thinking of making my own ducts after I get some other problems with my car "just to say I did it". ;)

Are you looking to ducts because you are getting some brake fade or just to get them?

volley1 12-11-03 08:31 AM

When I was at the Grand Prix of Denver I saw a different kind of setup on the Trans-Am cars. The had what looked like a small brake caliper, maybe three inches long, that fit over the rotors just like a caliper. They had 3 inch brake ducting coming from them and then routed to the front of the car. I assume that it dumps air directly into the vanes of the rotor. Anyone know where you can get something like that? Or do you know what I am talking about?

CrispyRX7 12-11-03 09:11 AM

For CWR CF brake duct install and some more pics.
I run these with 275 hoosiers on 17x10.5 front rims. No clearence issues. Not a fully ducted setup but much improved over stock IMO.
http://reganrotaryracing.tripod.com/cwcbrak.htm
FWIW,
Crispy

DigDug 12-11-03 10:30 AM


I looked into the same thing when I had some serious fade on the track back in September. I found the brake ducts at N-Tech:
Those would definitely work. So they have trouble supplying them? Maybe I can convince them to make some more...

Yes, I am looking to ducting because of fade. I am running Hawk blues, which are pretty good in terms of fade - for the most part, except for a few isolated situations (like turn 1 at VIR or turn 1 on Summit main), I really have to try to get them to fade. Now I'm looking for something to help with those "isolated situations"! I have heard from numerous people that the FD responds well to good ducting, so I sort of naturally took to that route.


When I was at the Grand Prix of Denver I saw a different kind of setup on the Trans-Am cars.
I have seen these as well - definitely a high-dollar solution (the ones I have seen were CF - fairly intricate). Very nice how they wrap around the rotor to envelop it with cool air, rather than just blowing against the back of the rotor - makes much more efficient use of the ducted air... If I could find these, I would definitely purchase them! However, I have never seen these on any RX7 - only TransAm and ALMS cars. But I wouldn't mind being the first! :D


I run these with 275 hoosiers on 17x10.5 front rims. No clearence issues. Not a fully ducted setup but much improved over stock IMO.
CrispyRX7, what do you mean "not a fully ducted setup"? Do you run them without hoses or something?

bradrx7 12-11-03 10:32 AM


Originally posted by DigDug
bradrx7, you run 265/65x18's? Wow, I thought I had clearance issues in the wheelwell! Is your car lowered significantly?
Digdug... I run 265/650x18 metric sized Dunlop slicks. this is the equivalent of a 275/35x18 DOT tire. The car is not slammed, but it is lower. My front liners are severly distressed <g> but I do not care and cut thme out to allow the oil coolers to vent anyway.

I'll try to attach a picture of me at Mosport. the car is leaning over in T1 and you can see how low the car gets at speed even though I run 1000/700 spring rates.

Also, the CWC ducts are worthless for track use without adding hoses.

DamonB 12-11-03 10:42 AM


Originally posted by bradrx7
Also, the CWC ducts are worthless for track use without adding hoses.
I agree. The N-Tech approach seems to be the most common solution found among other racecars and it would also make hose routing easier. Of course it also seems you could build something like that from scratch pretty easily...

Bringing more cooling air to your brakes will provide the same results as bigger brakes without the weight penalties. I remember some GTP cars having water misters inside the long brake ducts to effectively air condition the brake cooling air :cool:

CrispyRX7 12-11-03 11:02 AM

"worthless for track use without adding hoses"
Debatable. Define your parameters and assumptions. ;)
I get no fade at 140+ at VIR T1 and SP T1 using AP front brakes and "unpiped" CWR ducts.
Crispy

Mahjik 12-11-03 11:27 AM


Originally posted by DigDug
Those would definitely work. So they have trouble supplying them? Maybe I can convince them to make some more...

Yes, I am looking to ducting because of fade. I am running Hawk blues, which are pretty good in terms of fade - for the most part, except for a few isolated situations (like turn 1 at VIR or turn 1 on Summit main), I really have to try to get them to fade. Now I'm looking for something to help with those "isolated situations"! I have heard from numerous people that the FD responds well to good ducting, so I sort of naturally took to that route.

Well, they don't have problems supplying them. They have problems with people not needing them. ;) FD's are rare beast as it is let alone people running them on a track or on a track hard enough to need brake ducts. :)

You might try some competition pads from N-Tech (or some other place). I was told by several track guys not to use the Hawk pads for the track. The N-Tech FD Competition pads have been great so far (using the stock brakes and Super Blue for fluid). They usually only took a half lap to get warmed up (about 4 turns with hard braking at the track that's close to me) and never faded.

If the competition pads don't do the trick, then you might look into some brake ducts.

CrispyRX7 12-11-03 11:36 AM

Why would someone tell you NOT to use Hawk pads on the track? The Hawk Blue 9012 compound pads are some of the best track pads available...but they do make one hell of a mess. Sure there are other options but it sounds like the "other track guys" are merely noting a preference and not a deficiency with a Hawk pad as Hawk makes some very good track pads.
Crispy

Mahjik 12-11-03 11:54 AM


Originally posted by CrispyRX7
Why would someone tell you NOT to use Hawk pads on the track? The Hawk Blue 9012 compound pads are some of the best track pads available...but they do make one hell of a mess. Sure there are other options but it sounds like the "other track guys" are merely noting a preference and not a deficiency with a Hawk pad as Hawk makes some very good track pads.
Crispy

For others experience, they Hawks weren't worth the money (and some still had fade with them). Nick from N-Tech suggested his competition pads and I've been extremely pleased with them so far.

I don't have first hand experience with the Hawk pads at the track myself, only going on what others have experienced and then pasted on to me. So far, they haven't steered me wrong. ;)

CrispyRX7 12-11-03 12:06 PM

Granted Hawks pads have increased in price significantly over the last few years, are a bit agressive on rotors when cold, and make a nasty dust but I'd challenge anyone who says they are less than suitable for track use. As for Nick...well of course he would say his own pads are better - he wants you to buy his! Not that his pads are any less suitable - they are all good enough. And as for fade with Hawk Blues there are very few folks that I can think of that could beat on brakes hard enough to get blues to fade. If using any other compound - Blacks, HP+, HP, then sure but then again these are NOT *track* pads.
Regards,
Crispy
- use of Hawk Blues for 6 years with never a hint of fade

DigDug 12-11-03 12:21 PM

Yeah, I have to say I like the Hawk blues - they bite very well, and they are very consistent. I only have problems with fade into turn 1 at VIR at about 150, and into turn 1 at SP at about 160. Most of the time, they are plenty sufficient as they are...

I am running stock brakes within stock wheels, to which I have given a lot of thought. The stock wheels make sense for me because A) they are sufficient with the right rubber, and B) I have several sets of them! This limits the possibilities for brake upgrades, but honestly, I can work with the stock setup. I am just looking to get that little extra cooling to (hopefully) get rid of the little bit of fade that I do experience in those high-speed braking zones. Otherwise, I am pretty happy with my current setup.

bradrx7, your overall ride height looks roughly equivalent to mine, so your wheelwell clearance is probably tighter than on my car. Do you happen to have any pictures that show how you routed the hoses to your brakes? I am very interested to see how you ran them, because I haven't come up with a strategy that I really feel confident in. I keep worrying that they will get torn out on track in some convoluted situation...

CrispyRX7 12-11-03 12:47 PM

DigDug,
hehe can I ask what your engine setup is to hit those speeds at VIR and SP?
TIA
Crispy

Mahjik 12-11-03 02:23 PM


Originally posted by CrispyRX7
As for Nick...well of course he would say his own pads are better - he wants you to buy his! Not that his pads are any less suitable - they are all good enough.
I didn't call Nick to order Hawk pads from him (or any pads for that matter). I actually call him to order his brake ducts and Shark Mod. He only had a kit for larger brake kits but he said I could modify it to fit. After a little discussion, he said that the competition pads would take care of my problem without the ducts (even though the duct were more expensive).

I'm not even sure Nick sells Hawk pads anyway. ;)

DigDug 12-11-03 02:50 PM

As far as engine setup, I have a 13B with stock turbos. The key thing is the ECU - it is a one-off unit developed by Peter and Mazda Motorsports back in the IMSA days, and it has maps up to 15lb of boost. The engine is heavily ported, and the ECU was programmed on the dyno specifically for this motor to take full advantage of the breathing capacity. Its level of tune seems to be about as high as you can go with stock turbos and a 13B.

Surprisingly, it is VERY reliable - what Peter and Mazda figured out was that as long as you provide enough fuel, the motor is damn near bulletproof. Thus, foamed fuel cell, dual fuel pumps (each with its own pickup at one rear corner of the cell), surge tank, and bigger injectors. Oh, and I actually change the fuel filter! But once again, the really key thing is the ECU - it knows to run very rich at all times. And of course any efficiency- or emissions-related subsystems have been removed and the ECU doesn't deal with the inputs anymore.

Oh, and 2600lb dripping wet! That has a lot to do with the speeds I am seeing at the ends of the straights, because I can carry a lot of speed out of the preceding turns...

Anyways, sorry to wander off there. I was sorta surprised recently when I went to buy a new set of Hawk blues, and they seemed to have gotten cheaper (about a month ago I ordered them through RPW). I think the fronts were about $90 and the rears were like $60, but I'd have to check the invoice to confirm that. That's not too bad for these pads...

DigDug 12-11-03 02:57 PM

Back on topic... Mahjik, so do you know these guys at N-Tech? Have you asked recently if they are still not making those pieces? Is it even worth the time for me to email them and ask?

Mahjik 12-11-03 03:09 PM


Originally posted by DigDug
Back on topic... Mahjik, so do you know these guys at N-Tech? Have you asked recently if they are still not making those pieces? Is it even worth the time for me to email them and ask?
Bascially Nick said there would be no more production runs on the Brake Ducts unless there is a demand for them. I think he has to make productions runs of at least 10 kits, but I'm not sure about it. I don't think he'll make a production run of 10 or more kits just to sell one or two of them. :( This was back in September. You can email him or PM him on the forum here:

https://www.rx7club.com/member.php?s...o&userid=10595

I know he has an account here but I'm not sure how often he visits the forum. He does respond to emails fairly quickly though.

bros0000 12-11-03 04:18 PM

I bought a set of Nick's backing plates back in August, he mentioned that they were the last set he had for the stock brakes, but they needed some machining before he shipped them. I have since gotten them onto the car (with some fairly major work of my own on the steering knuckles with a file...), but haven't had a chance to pick up hose yet.

Brad, I would second the request for pictures if you have them... :D

bradrx7 12-11-03 04:29 PM

Digdug,
Crispy and I both know Nick (N-Tech) very well. Just send him a post and tell him what you need. Although he did not make my backing plates, his are similar... hell, they all are when it comes to it. The big issue is fitting them to your disc size.

Regarding routing the hose, no I don't have any shots. It is fairly straightforward once you have backing plates. The inside front edge of your tires DO eat up the hose some, but that just becomes a 'wear item'. run the hose directly toward the engine, ty-wrap the hell out of it, then run the hose forward staying parallel to the 'frame' rail. Then forward to you collector. I use a GTC nose and fabricated collectors, so your setup will vary. just use your head and don't worry about rubbing. The tire is harder than the tubing.

Cripsy, I agree those are some stout speed numbers and a very light weight. Digdug should be sure to look us up at VIR in the summer. <VBG>

DigDug 12-11-03 07:03 PM


Originally posted by Mahjik
Bascially Nick said there would be no more production runs on the Brake Ducts unless there is a demand for them. I think he has to make productions runs of at least 10 kits, but I'm not sure about it. I don't think he'll make a production run of 10 or more kits just to sell one or two of them. :( This was back in September. You can email him or PM him on the forum here:

https://www.rx7club.com/member.php?s...o&userid=10595

I know he has an account here but I'm not sure how often he visits the forum. He does respond to emails fairly quickly though.

Cool, I'll shoot him an email and see what he says. If he doesn't want to make them, are there any other suppliers of comparable plates?


Regarding routing the hose, no I don't have any shots. It is fairly straightforward once you have backing plates. The inside front edge of your tires DO eat up the hose some, but that just becomes a 'wear item'. run the hose directly toward the engine, ty-wrap the hell out of it, then run the hose forward staying parallel to the 'frame' rail. Then forward to you collector. I use a GTC nose and fabricated collectors, so your setup will vary. just use your head and don't worry about rubbing. The tire is harder than the tubing.
Your description makes perfect sense. That is exactly what I came up with when I sat down and tried to think of where to run the hoses, but I was concerned about full steering lock (outside wheel), and what the hose would do in that case. As long as it can be made to "squash" rather than bending out to one side, it should be okay. Do you have any observations about this on your car? I guess if you're running them on track, they must seem to behave decently well down there...


Cripsy, I agree those are some stout speed numbers and a very light weight. Digdug should be sure to look us up at VIR in the summer. <VBG>
Hehe, you know I recently obtained a passenger seat that I can drop in to give ride-alongs! ;)

Provided everything goes as planned between now and then, I should be at VIR several times next season. I'll let you guys know ahead of time when I'm going. Meanwhile, winter is boring... :p:

Mahjik 12-11-03 09:03 PM


Originally posted by DigDug
Cool, I'll shoot him an email and see what he says. If he doesn't want to make them, are there any other suppliers of comparable plates?
The only other one I found (in my quickie searching) was just the Crooked Willow ducts already mentioned.

I don't think it would be that bad to fab something up to bring air up from the nose (especially if you already have the nose ducts for the brakes from a chin spoiler or aftermarket front end).

I'm wondering if there are any companies in Japan that might make something compareable to N-Tech's product. I'm sure they have many more track FD's over there than we do here in the US.

DigDug 12-11-03 09:10 PM

I just got an email back from David Breslau at Widefoot Racing - he is the guy that designed and fab'd those CWC ducts. He is no longer distributing them, as he now has his own company. He says he is making a few revisions to the design and will have them available again in early spring 2004. I haven't gotten the price yet.

So that's an option...

skunks 12-11-03 09:33 PM

are the 2 spindels exact mirrors of each other? im asking cuz i might actually make some of these. im assuming they are cuz i dont wanna have to dissassemble both sides if i dont got to. also, is there really a demand for these? who would actually pay for them? how much do you think a resonable price would be and how thick do you think these things should be?

also, anyone care of it was made out of carbon/kevlar (it would kinda look like colored brake calipers if nothing else hehe :)) what kinda hosing would you also need, would anyone care if they came without hosing? also if i were to make mines, i would not make it so it would slant foward, mines would be like the n-tech ones, hose only type of thing where it would go straight back and you coudl just simply ziptie the hose to the steering arms. so it would follow that.

volley1 12-11-03 09:33 PM

Why don't we find someone that makes the things I was talking about that fit over the disc? Probably better cooling from them.

rockshox 12-11-03 09:44 PM

i would think the best cooling would be from directing air into the hat portion and letting the discs spin it out. blowing air from the outside edge just seems backwards. not to mention the hose would have to travel a lot further because its farther from the spindle pivot.

DigDug 12-11-03 09:50 PM

If you look closely at these, I think this is what you're referring to...

http://www.ntechengineering.com/images/nt00139.jpg

These are the N-Tech backing plates. I looked again and noticed that the swept surface of the rotor was entirely exposed from behind the plate. That is pretty nice!

skunks 12-11-03 10:15 PM

ok, apparently i will be making these. stay tuned for more info/pics

artowar 12-11-03 11:05 PM

I believe that Hoerr Racing carries ducted carbon fiber backing plates. Check their catalog.

DigDug 12-11-03 11:26 PM

http://www.hrpworld.com/

bradrx7 12-12-03 10:13 AM

Guys, if Nick doesn't want to make a new run of backing plates, go to your nearest roundy-round fabricator shop and ask them to make you some. This really isn't rocket science. Also, the backing plates fit the inside of your rotors, not the outside edge. They should fit tightly.

DigDug 12-12-03 11:15 AM

If somebody already makes them for the FD, I consider it worthwhile to find them - and not have to deal with having someone make custom pieces. It is a pain in ass to have to deal with measurements, fitment issues, etc... It is far easier if the parts are available for our car.

I am waiting to hear back from Nick...

DigDug 12-12-03 12:31 PM

I just heard back from Nick. He will make them if we can come up with 5 orders, and he has to know the brake setups for those 5 pairs ahead of time (obviously). They are made of aluminum. The website lists a price of $225.

Anybody else interested? I know I am...

bradrx7 12-12-03 03:15 PM

Nick's price is very fair. Go for it.

Coulthard Fan 12-12-03 03:42 PM

Well, I'm interested so I emailed Nick about these last month... and never heard back from him. My question was:
"On the brake backing plate inlet ducts you sell for 12.4, 13 and 14" diameter rotors, since they all attach to the back side of the center of the rotor, why does it matter what size diameter the rotor is? Do none of these work with stock FD 11.6" diameter rotors, such that I'd have to upgrade the rotors/calipers before I can install your ducts? Optimally, I'd like to install the ducts on the stock rotors, use that setup until I'm at the limits of the stock brakes, then go to more trackworthy equipment and reuse the same ducts. Is that possible?"

Any thoughts from the peanut gallery?


Originally posted by DigDug
I just heard back from Nick. He will make them if we can come up with 5 orders, and he has to know the brake setups for those 5 pairs ahead of time (obviously). ...

bradrx7 12-12-03 04:10 PM

CoulthardFan, the duct needs to fit tightly to the inside edge of you rotor for utmost efficiency. That means the outer diameter of the duct which replaces your stockbacking plate must be a little smaller than your rotors inside back opening. My 330mm rotors' backing plates would be too large for your stock backing plates. make sense?

DigDug 12-12-03 04:51 PM

So CoulthardFan, are you saying your interested in getting a pair? That would be 2 down, 3 to go on the order...

gfelber 12-12-03 06:38 PM

Here's a shot of N-Tech's backing plates
 
http://www.mantissaracing.com/Mantis...%20ducts_2.JPG

The front ducts are custom made AL units courtesy of Brad Barber.

Thanks again Brad!

Regards,

Gene

DigDug 12-12-03 06:46 PM

Bingo. That's the picture I was asking for earlier!

skunks 12-12-03 10:56 PM

tomorrow i should be getting the backing plates from bigislandseven, should have a set or 2 done by this week

BTW: mines will only run about 150 bucks :)

also, mines will be made of kevlar if one wants, remember kevlar comes in any color you want so it can match your brake calipers as well as your car color hehe


Coulthard Fan 12-13-03 10:33 AM


Originally posted by bradrx7
CoulthardFan, the duct needs to fit tightly to the inside edge of you rotor for utmost efficiency. That means the outer diameter of the duct which replaces your stockbacking plate must be a little smaller than your rotors inside back opening. My 330mm rotors' backing plates would be too large for your stock backing plates. make sense?
BB - so what you are saying is that it is the inside back opening that is different sizes on the various size rotors. I guess I figured that they would all be very close to the same size, no matter what the overall diameter of the rotors.

DigDug - I really don't care where I get them from, but I do want a set. As my question to Nick implied, I'm stilll running stock calipers/rotors but plan on upgrading later in 2004 to a yet-to-be-determined setup. So if I need to know what that setup is before ordering... and I can't use them with my current setup... and it will be almost a year before I upgrade... ah, fuck it... I'm in. I guess I'll have to just decide what setup I want and will sit on the backing plates (figuratively speaking) for a year if you need critical mass for some kind of group buy.

bradrx7 12-13-03 09:03 PM

Re: Here's a shot of N-Tech's backing plates
 

Originally posted by gfelber
http://www.mantissaracing.com/Mantis...%20ducts_2.JPG

The front ducts are custom made AL units courtesy of Brad Barber.

Thanks again Brad!

Sure, Gene. I'm glad you are putting them to use, buddy!


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