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New Brake Ducts - Quantum Motorsports

Brakes
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19K views 49 replies 24 participants last post by  booster 11  
#1 ·
Well I finally got smart and put some brake ducts on my car for my track days. I had not previously installed ducting because I was worried about how this would effect the daily driving of my car. I guess I didn't realize this was something that could be removed somewhat easily.

Well after seeing an add in Grassroots MotorSports I contacted a company called Quantum Motorsports about their upcoming Impreza brake ducting kit. I received the kit in mid September and installed it to be ready for a weekend at Putnam Park in IN.

I am impressed with the kit and the quality of the actual duct. The only let down I had was the hose was not what I expected and I actually went to my local race shop to buy different hose to use. Other than that I love this kit. The inlet is on top of the rotor and there is metal to protect the ball joint. The air inlet actually goes over the ABS which may help prevent frying that. The kit also came with some adapters for mounting the hose in front but I couldn't quite make those work well. I bought USDM fog lamp housings from Subaru Genuine Parts and routed the hose through those in the front and used the supplied brackets to help hold the hose in place.

I took a bunch of pictures of the install. The orange hose is the "good stuff" and the silver hose is what came with the kit.

I used some temp strips on my calipers and my temps stay in a very reasonable range. This is the first event for me all year that I have not boiled my fluid and had my pedal go to the floor. I attribute this to the brake ducts.

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M
#3 ·
Really nice!

I dont care for the inlet at the bumper tho. I have seen some nice CF inlets that replace the entire rectangle panel.

Also, it's important that the air is fed to the "eye" of the rotor, not the face. Is the inner diameter of the rotor big enough to accept all of the air or is some of it being lost to the rotor face? The outlet looks really big compared to the RCE version.

http://www.racecompengineering.com/images/item/rcebrakeduct_large.jpg

See how they reshape the outlet to empty just in the eylet?

Anyway, Nice stuff and you will def love it by looking at the temp signs on your rotors/calipers!
 
L
#4 ·
Andy,

+1 on the kit. I was the first one to use the kit. Shame I didn't post earlier. Anyways, the design of the duct (large and hence open flow to the rotor vs. others which are reduced to fit the hub-bottleneck) was what got me.

Not terribly impressed with the hose either but the kit was significantly less than some of the others I had seen.

Question on the install for the passenger side. I have an 04 and I removed the air silencer but routing it to the front of the car was a bit of a pain (less clearance due to some tank like object). That said, I also believe you can get a better flow if you just cut the liner with a dremel and pass the hose straight through. During install of track pads and wheels, get the hose in there too and make sure you don't turn the wheel all the way through ;)

I'd be curious to hear how you got the passenger side hose through.

Pad wear MUCH better and we wore (ready for this) about 10% of the front pad in one day with two instructors sharing the car.

Kudos to Quantum for a good product and great service.

Lutfy
 
M
#5 ·
+1

I esp like the touch of keeping a bit of a heat shield for the ball joint!

I'm still thinking that the "dump hole" may be wasting some efficiency by being so far "out" from the rotor eye/center. That may cause it to dump a lot of it's air onto the one side face of the rotor which is not nearly as good as dumping all of it into the eye. Do you have any pics or measurements that show this? I used to have BrakeMan rotors that had a really big rotor ID, now I have Stoptechs that have a smaller rotor ID. The BM would have been fine with your setup but the ST wouldnt get the full benefit unless it could focus the air more towards the center.


BTW,

Check out this inlet design. I'm jealous because no-one makes anything like this for 2006:


Scoobyparts Ltd CHARGESPEED CARBON FIBRE BRAKE DUCTS


Here's another view:

Chargespeed Brake Ducts - Carbon Fiber - 04-05 WRX/STi




:D
 
#7 ·
mxpop said:
+1

I esp like the touch of keeping a bit of a heat shield for the ball joint!

I'm still thinking that the "dump hole" may be wasting some efficiency by being so far "out" from the rotor eye/center. That may cause it to dump a lot of it's air onto the one side face of the rotor which is not nearly as good as dumping all of it into the eye. Do you have any pics or measurements that show this? I used to have BrakeMan rotors that had a really big rotor ID, now I have Stoptechs that have a smaller rotor ID. The BM would have been fine with your setup but the ST wouldnt get the full benefit unless it could focus the air more towards the center.


BTW,

Check out this inlet design. I'm jealous because no-one makes anything like this for 2006:


Scoobyparts Ltd CHARGESPEED CARBON FIBRE BRAKE DUCTS


Here's another view:

Chargespeed Brake Ducts - Carbon Fiber - 04-05 WRX/STi




:D
Click to expand...
Check this out. im looking at getting a set of them

Sorry these first two links dont have pictures

Carbon Fiber:
Chargespeed Carbon Fiber Fog Light Brake Ducts for 06+ Subaru WRX & STi

FRP:
Chargespeed FRP Fog Light Brake Ducts for 06+ Subaru WRX & STi

Here are the pictures
CHARGESPEED

CHARGESPEED
 
K
#6 ·
Even if it might not be the best design for pumping air to the center of the rotor, this defiantly looks like a good deal compared to the $400 RCE kit. It doesn't seem that it would be too bad to modify to pump the air in there more efficiently too.

What about their hose didn't you like?
 
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L
#8 · (Edited)
KrazyKarl said:
What about their hose didn't you like?
Click to expand...
I should have said " I didnt like the hose due to my screw up ". Actually its a better design since the fabric is stiched individually on a metal wire so when there is a rub (wheel/tire) you are not wearing out the hose material. That part, I was happy with.

Due to my negligence, I didnt leave enough room by turning the wheel left lock and right lock to ensure the hose was not stretching. Long and short, the hose ripped and then fell on the drive shaft which later on collected the metal wire and wrapped the darn thing on the shaft blowing off both (inside and outside) boots which sprayed grease all over the damn well and it also scored the stock rubber brake hose (I upgraded to the SS ones later which I should have done anyways).

Again, I take ownership of being an idiot. So what did I not like about the hose "if you are not careful you can have the wire damage your drive shaft" which would have not been the case with the other silcone/neoprene hose.

Lutfy
 
M
#10 ·
You are correct STIGUY, those are available for 2006 but their design is uninspired compared to the earlier designs.

What I meant to say is that there are none available that function any better than simply using the stock gutted fog light holes. As you see in your links, the earlier versions make great use of funneling the air in while the 2006 one simply copies the stock design. I would love to find some that actually improve on the stock design!

Check out the links in my sig.

As you can see in these pics of my silver car, I am using the fog light holes as inlets. They work OK but def have room for improvement. I am actualy thinking of making some brake inlets at the outer edge of the lower grill opening between the splitter supports and the silver bumper. That area is wasted space at this point and is in a better pressure zone than at the sides. Putting the smooth covers back over the foglight holes will make for better aero as well.

That is project #27 on a list about 80 items long.....:lol:
 
#12 ·
This looks like a pretty nice kit, but there is a bit on misinformation here in terms of comparing it with the RCE kit. First, the RCE is $300, not $400 as somebody mentioned above. The other thing to consider is that the RCE kit comes with the highest quality hose available. The standard hose alone costs over $75, and the optional high temp hose is even more. There was also a lot of testing that went into ensuring that as much air as possible is sent directly to the center of the rotor, where it is by far the most effective, just as mxpop was saying. We could have kept the cost down by using an inferior hose or a design that is easier to produce, but as many of you know we often try to design parts to perform as well as they possibly can, which unfortunately does increase the price in some instances. I'm not putting down the Quantum kit, just trying to let you all know that there is a reason why the RCE kit costs a bit more.
 
L
#13 · (Edited)
BoostJunkie said:
This looks like a pretty nice kit, but there is a bit on misinformation here in terms of comparing it with the RCE kit. First, the RCE is $300, not $400 as somebody mentioned above. The other thing to consider is that the RCE kit comes with the highest quality hose available. The standard hose alone costs over $75, and the optional high temp hose is even more
Click to expand...
Well come one guys. Hose for over $75? The 300 degree neoprene hose runs for $5.5 a foot and that is 'retail'. Each side use up 3 feet which would equate to: 3*2*5.5= $33 for the hoses. The higher temp (orange in color) runs for $6 a foot hence $36 total.

The hoses are pretty standard, the ones you get from your local aircraft or small airport maint shop is pretty much the same in terms of quality (black = 300 degrees, orange = 500 degrees).

I agree with the fact that the price would include engineering, R&D. I am no engineer but I wouldnt waste time comparing flow rates on different kits to see which one flows better. Brake ducting is a simple process.

FYI:

Race Car Brake Temperature Control ducting, ducts and equipment
 
Q
#14 ·
Never posted here before. Hopefully it is okay to post here being a vendor and all...

Andy, I am sorry to hear that you didn't like the hose and replaced it with a more garden variety race hose. Please keep in mind the hose we supply in our race kits feature a temperature range similar to that which you replaced it with. The big difference is that our hose features an external wire that is mechanically bonded to the hose fabric. This external wire acts as a wear strip against your suspension components protect the hose from developing holes. This is essential on a street car, as these cars were never designed to have a 3" hose run anywhere near the suspension. I fear that the hose you replaced ours with will wear a hole in no time.

As far as the inlets go, they appear to be installed incorrectly I'm afraid. Those are designed to work with the stock STi covers that do not have an opening. Since it appears you are using a stock WRX cover, you could probably install them behind the WRX cover and that would make for a cleaner look. We actully have an inlet specifically for the WRX that is designed to fit behind the cover and if I knew you had those paticular covers I would have recommended different inlets. Don't get me wrong they will work just fine as installed, they just may not look the cleanest.

Those other fog light opening insert pictures posted are nice pieces. I wish we had the capabilities in house to form carbon... By all means if you can afford them I recommend them. Just be sure to pair them with our duct plates and hose. :)

Again if my post is against board rules please remove it. I just thought I would take the time to explain a few things about the kit as we have yet to get our hands on an STi, to officially let the pictures on our site do the talking. (all testing and pictures done on a standard 2004 WRX)

Thanks,

Jon Lambert
Quantum Motorsports
 
#15 ·
Jon, by no means was I critising the inlet adapters. I know I didn't have it the "right" way I just needed something to keep the hose from pulling out. Not pretty but it worked. As far as the hose goes - I do think it would work well, but I tore a couple of sections of it during the install when I was checking wheel clearance. I just feel the length supplied was not enough and the hose is not stretchy.

I am going to call you about the inlet adapters for the fog lamp housing tomorrow. I really like this kit and the quality of it. :tup:

My whole post was not made to compare between the RCE kit and this but just to show the option that I bought. I have spent a fair amount of money at RCE and I will continue to do so. It's just nice to see others making products for our cars - especially for those of us who really use these things and don't just drive on the street.
 
Q
#20 ·
Andy,

I know that your post was not meant to criticize our kit in any way. I just wanted to clarify a few things about the design and installation on an STi. As I said earlier our site contains no 2005-2007 STi specific information right now.

As far as the hose issue, we are going to include an additional 8" per side for the STi kits. That should solve the problem you had with the hose. It is essential that the hose not be under tension, so having enough hose is very important. We try to give more than enough in all of our kits, and with the new added length I think that will now be the case with the STi kit as well.

This being said, I wish you would have called us when you experienced this problem. We would have gotten some more hose out to you ASAP. It would have prevented you from spending additional money on hose.

Jon Lambert
Quantum Motorsports
 
#21 ·
I used the quantum kit and to be honest I bought 12' of the super awesome 3" high temp orange hose exactly like tone stuff in the photos at the top at the VIR store for 69 dollars back in July and still had it in the box. I was planning to cut and weld pieces of pipe onto my factory heat shields and cut them all up.

Basically I had the quantum design in my head, then low and behold I saw the ad in grassroots and looked it up. What attracted me to the quantum kit was the fact that I could buy just the plates for 75 bucks. There they were for cheaper than I could spend my time messing with the factory flimsy thing.

I Love RCE but I just couldn't go with their brake kit due to the fact that they don't break it up.

They shipped their product fast and the attention to detail like a 10 page(?, its big whatever it is) instruction booklet is pretty awesome. It isn't rocket science but they really went the extra mile to produce that.
 
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K
#24 ·
I have had several customers with ducts on corvettes that cause rotor problems with ducting pointed right at the inner rotor face. Whatever you do - remember that cast iron is POOR at several things mostly related to the microstructure.

It is poor at heat cycling to 'high' temperatures - i.e. thermal cycling

It is poor at rapid heating or cooling - related to point three.

It is poor at uneven heating/cooling.

It is a fairly brittle, hard, and strong material. Consider your designs accordingly.
 
#26 ·
Why do cast iron engine parts behave differently? ;)

And I just bought a pre-loved RCE kit. The previous owner provided me with new hoses. I am really excited to install this beautifully engineered piece of brake-love. Just gotta order some '06 AW fog covers...
 
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K
#27 ·
I had to do some research -

But in general - engine blocks and other parts like that have to use a different type of cast iron - either a different form of gray iron that is stronger and more crack resistant - or I believe in some cases nodular iron (like certain stronger cranks in older engines).

This generally means reduced carbon content which reduces thermal properties but improves strength properties - very significantly in the case of nodular iron (which allows smaller parts)

There is also CGI - a special form of iron not yet widely used but quite interesting as the benefits are quite large.

This link has a good explanation of some basics -

Iron engines may be in your future

Back to the topic at hand - the properties of rotor iron indicate that rapid and uneven heating or cooling can be quite detrimental to rotor life. This data should be well respected when it comes to designing a cooling system for a brake rotor.
 
Q
#28 · (Edited)
Well there seems to be some debate about the design of our kit and the fact that it may not look as if the air is focused at the center of the rotor.

All of our kits are designed to focus the air at the center of the rotor without sacrificing the airflow of the supplying air line. Keep in mind that to achieve the maximum efficiency of the system the cross section (i.e. area) of the duct should never be less than that of the supply hose. After all what good is it if you have a 3" hose supplying a duct with an outlet that has the effective cross sectional area of a 2 1/2" or 2" tube. It is like blowing on a straw that has the end pinched, to put it plainly.

If you view our duct parallel to the rotor it may look as if some of the air is hitting the inside rotor face, but if you view along the air path itself (down the center of the tube) you will see that all the air is focused on the center of the rotor. Keep in mind the air is going to follow the path of the tube, and also as another poster pointed out, that the rotor itself acts as a pump and draws the air in to the center.

Take a look at the picture below of our 3" Mustang kit.

Image


This kit is similar in design to our STi kit. If this were viewed parallel to the rotor it would look as if all the air were not focused at the center. But as you can see when you view it down the center of the tube that it truly is all directed at the center.

Please keep in mind that we are first and foremost an engineering company. We have actually done a classical thermal analysis on the 13" Mustang Cobra rotor to prove the added benefit of evenly cooling both sides of the rotor.

No modifications should be necessary to make our kit function properly. It should work for anyone, no matter what rotor you are running, right out of the box.

Hope this clarifies a few things.

Jon
 
K
#29 ·
I definitely tried to simply say what I know about rotor failures and why and how some of them occurred. I have seen plenty of home brewed cobbled kits that were simply excess weight and random loose flapping junk hanging on the car. - I assume you have some experience there as well if you make a bunch of these kits. And while I like what RCE has done - it's pretty complete etc - some alternatives are always nice for users and rightfully forces RCE to do the right thing - which I firmly believe they have as well. I will likely be sporting one very soon.

For the price of either kit - I have a pretty strong suspicion that if you do as little as 3-4 events a year it would pay for itself pretty quickly and then some.
 
#30 ·
WRXBrakes said:
...For the price of either kit - I have a pretty strong suspicion that if you do as little as 3-4 events a year it would pay for itself pretty quickly and then some.
Click to expand...
Something which I am looking very much forward to finding out. I think for the STI, either kit will be a vast improvement over no ducting at all.
 
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#33 ·
Bump for more conversation on these ducts.

Did anyone purchase the "air inlet mounts"?

how are those installed? anyone have picures?

usdm foglight:
Image


air inlet mounts:
Image
 
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