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Brake cooling ducts - anything new??

114K views 257 replies 56 participants last post by  JosephAtTheTrack 
#1 · (Edited by Moderator)
I was wondering about any new brake cooling duct solutions. Stillen was supposed to have a kit out "soon" back in mid-2009, but I just checked on their web site and nothing yet.

I had my front lip off the other day and I was wondering how the Spec-V routes air to the wheel well for brake cooling via the inlet duct on the front lip. Anyone have a picture of this lip/undertray from the top with it off the car?



I found a picture of the Mine's lip brake cooling duct, and was wondering if the Spec-V is the same.





At Mosport I had a good look at the way the Brass Monkey team route the air into the front rotor centers with a simple backing plate attached to the caliper (Stoptech for them) and a 3" or so silicone hose. I have pics and will try to find a good one to post up. But they have a deep front lip which is not so suitable for road use with large "irregularities". It also looked like they were taking air in from the back edge of the undertray rather than from the front part of the lip, but I didn't get a good look at that part of their brake cooling duct solution.

Anyone know of any new cooling duct solutions? I would really like some as I am sure many others would.
 
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#4 ·
I have to admit that I couldn't resist doing this mod - so cheap and so inconspicuous
. Can't really tell if it helped since I had never had my brakes give out before I put them on (Granted I put them on the same time I did the tranny cooler so my hot laps went from 3 to 6-7). Even with doing more laps = no brake fade at all.
 
#3 ·
It is one of the things I am working on here at Stillen.

There is the active cooling system on the racecar, but I don't think anyone has been 100% happy with the solution so far. It does work.

I have been talking about it today, and it is something that I personally feel is important to help the life of the rotors and pads on a GT-R that is tracked.

The problem is front mounted caliper and all wheel drive. If the caliper was rear mount, there would be a lot of room for ducts to force air though the center of the rotor. If the car was rear wheel drive only, there would be a lot of room to mount the ducts.
 
#7 ·
It is one of the things I am working on here at Stillen.

There is the active cooling system on the racecar, but I don't think anyone has been 100% happy with the solution so far. It does work.

I have been talking about it today, and it is something that I personally feel is important to help the life of the rotors and pads on a GT-R that is tracked.

The problem is front mounted caliper and all wheel drive. If the caliper was rear mount, there would be a lot of room for ducts to force air though the center of the rotor. If the car was rear wheel drive only, there would be a lot of room to mount the ducts.
Sean, I've read many people say this, but I don't agree. When I had a look under my GT-R with the undertrays off, there is plenty of room to get air into the rotor center behind the caliper and between the axle.

Here is proof that it can be done very simply as shown on the Brass Monkey race car I photographed at Mosport. as one of the cars had had an off at turn 3 during practice and torn off the undertray, one of the crew guys was repairing their leaking tranny cooler that got punctured, and doing some other work under one of their cars. He was very nice and let me take some pictures of their brake duct cooling solution.

Here is the front lip/splitter from the car that didn't go off. Notice no cooling inlets on the lip.


Next here is a pic showing the stoptech brakes and the brake cooling hose:


Next is a picture showing the aluminum air inlet from the back of the undertray. I didn't get a shot of how this actually gets the air in. You can also see how they have opened up a hole with mesh cover to let air out of the nose, for engine cooling I imagine.


Next is rear brakes with no cooling ducts. Penske dampers too.


Crew at work changing springs (notice rear dampers are out)


Their aluminum auxiliary cooler duct and broken undertray:


Shot of their cooling duct hose into the space behind the caliper and in front of the axle boot:



Closeups showing the black brake duct cooling air outlet custom fitting, attached to the front upright (see that Stillen logo on the damper fork):



Brake duct hanging loose on the car that was the victim of an "off":



So a brake cooling duct solution can obviously be made to fit the front brakes on the GT-R. The OEM Brembo calipers have a center fixing bolt which divides the inlet area to the rotor center into a top and bottom part, but aside from that, should be possible as shown on the Brass Monkey car.
 
#5 · (Edited by Moderator)
I talked to Kyle at Stillen a few weeks ago and it sounds like they might be getting close to a cooling solution with the duct-work. The are also considering a rear cooling kit. Those of us who still use VDC (nearly 80% from my poll) should consider the rear kit as well. with VDC on, the car uses the rear brakes to make individual corrections and keep the car in line so they heat up more than cars running VDC off. Im hoping it wont be too much longer before these are finalized.
 
#9 ·
A picture of the Nissan factory race car's brake cooling inlets on the front lip, which I would assume is a nice high pressure point to get lots of air in. I would really like to know how they get air from that to the back of the undertray.



Here is a view of the top side of the OEM front undertray. It is very different than the Mine's carbon one as it is much thicker and made from some structural plastic for stiffness. So it is a little difficult to see how to sculpt it out to fit brake ducts as on the Spec-V or the Nismo car above.


 
#12 ·
Descartesfool:

Am I seeing aluminium foil wrapped around the brake lines as a form of insulation? Neat trick.

Thanks for the pictures btw. Our cars so desperately need the front brakes cooled with a quality solution. I don't think the rears are important as mine don't get hot even if I leave VDC on; at least they don't seem to be as the rear XP12s just aren't wearing much at all; (although every track is different I know).

Bish
 
#13 · (Edited by Moderator)
check this out for the rear brake cooling...

this is from nordring, its frp and it feeds the rear brakes on the side skirts.






password:jdm also have a front lip with ducts, autoselect have ducts in the front lip but you have to run ducts to the brakes which i dont think are included. shadow sports have a setup too with ducts like the spec-v. doluck have a really good solution that looks nice.
 
#17 ·
Downforce front lip replacement looks good, but I still do not see how the air from the inlet duct gets routed to the back of the lip to connect to a hose. I assume it is coming.
http://www.nagtroc.org/forums/index.php?showtopic=40774

I am surprised if people do not need any more cooling than a spatula can provide. I put AP Racing temp paints on the vanes of my rotors, and all 3 paints (green, orange and red) turned white. There was some hint of the red left, but not much. That indicates brake rotors are getting too hot and pads will wear much more quickly than designed and braking efficiency is reduced, with potential for fade. Plus extra rotor wear. I have never seen a fast/heavy race car without brake cooling ducts. They are an essential part of every race car I've seen in recent memory. You may not need them if you don't push really hard on track. But without knowing the temps from temperature indicating paints on the vanes, you don't know what temps you are running at.

Luckily the rear rotors seem fine and my XP-12's did not wear out, but I swapped them for Hawks all around when I changed the fronts. I also always drive with VDC on.

And brake cooling is not a $5000 problem. Look at what Brass Monkey racing put together: 1 adapter at the wheel, 1 hose, 1 adapter at the inlet, and a couple of clamps. I can only assume they put in as much brake cooling as they felt they needed on track. A nice front lip will of course raise the price, but that Downforce add-on one at $1495 seems like an affordable and nice piece, requiring some work on the OEM lip.
 
#18 ·
Downforce front lip replacement looks good, but I still do not see how the air from the inlet duct gets routed to the back of the lip to connect to a hose. I assume it is coming.
Sorry I assumed you needed a starting point(ie where to source air from) to apply a custom adapter and high temp hose to route the air.

I did this on an STI a few years ago. Don't have access to the pics at the moment and I forget who made the caliper brackets(maybe Race Comp Engineering) but I can dig up the pics when I get home and/or try to figure out who made the brackets and maybe the combo of a vented front lip + high temp hose + brackets will work. Won't be a complete solution, but could also get someone like Downforce etc on the right path to put one together at an affordable price. I'll update with the pics shortly.
 
#20 · (Edited by Moderator)
It was race comp engineering as I thought:
http://racecompengineering.com/osc/product...products_id=119

$440 gets you two carbon fiber ducts(for an STI) and 2x 500* hoses.

Here are pics of the RCE STI brake cooling kit I ran with their metal ducts(sorry I can't find any installed):




Just need a similar "kit" for the GT-R plus the new lip or as DMG Godzilla said just some molded vents that can be installed DIY.
 
#22 ·
The Mine's Type II front spoiler requires you to cut the inner linning of the wheel well. If anyone has a parts catalog for the vspec it would be worth looking up the part no. or diagram of the vspec inner linings v the standard inner linings
 
#23 · (Edited by Moderator)
Someone needs to come up with an easily installed kit similar to Brass Monkey's setup. It could attach to a lip/splitter with inlets. I'd buy one if it wasn't ungodly expensive.
 
#24 ·
Do Luck lip looks good too at $2600 for lip only I assume and possibly extra for brake cooling. I still haven't seem how the air gets routed from the front of the lip to the brake rotors on any of these aftermarket setups.

I am looking for ducts that go from the front lip to the center of the rotor, aka that STI part, and the Brass Monkey racing car (although no idea where they pick up the air). Ideal would be that small inlet as on the Spec-V plus some mods to the OEM lip to get a round duct from the rotor connected to the undertray's rear side and to the front of the lip. Deflectors as used on Porsche GT2's, GT3's, and Cup cars only work well if they have been designed in a wind tunnel. I am assuming the Spec-V was also designed in a wind tunnel as was the regular GT-R, including the Spec-V's extra aero bits.

Just fitting what looks like a good solution in terms of aero rarely works. There was just the head aerodynamicist from a Formula 1 team on the TV show Mobil 1 The Grid the other weekend, and he said 99% of stuff you try in the wind tunnel doesn't work. What you think will work usually does not, he said. I would assume he knows what he is talking about.

Virtually every tin-top race car ducts air direct from lip (high pressure area) to rotor center as that is the most likely way to get enough cooling air in. But there are always other solutions.
 
#29 · (Edited by Moderator)
Do Luck lip looks good too at $2600 for lip only I assume and possibly extra for brake cooling. I still haven't seem how the air gets routed from the front of the lip to the brake rotors on any of these aftermarket setups.
$2600 for a lip!!!!


We should be able to do this for la lot less if we mod our own.
 
#25 ·
In terms of spending a large pile of cash on a fancy front lip, here's something to consider.

Brass Monkey's fancy carbon lip, or what's left of it from a single off at turn 3 in Mosport:


A quick fix to hold it all back on for the race:


Racing with a lip


And without one


Really wanna spend a ton of money for that fancy front carbon lip??? It was lost in about 5 seconds as he went in a little too hot into the corner entry and car wouldn't turn in, and that was just in practice, no other cars involved.
 
#26 · (Edited by Moderator)
this is the new nismo R35 with bad ass brake ducts
Wheel Tire Car Vehicle Hood


here is the nordring lip..
Hood Automotive design Grille Bumper Automotive exterior


here is the install to make the holes to the ducts...
Tool Bumper Revolver Automotive exterior Trigger

Hand Hood Automotive tire Gesture Automotive design

Motor vehicle Gas Machine Automotive tire Auto part


more photos... see the duct in the center?
Grille Automotive lighting Vehicle Hood Motor vehicle

Automotive tail & brake light Grille Automotive lighting Motor vehicle Hood

Grille Hood Automotive lighting Automotive design Motor vehicle
 

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#30 ·
Brake ducts only work if they are in extremely close proximity to the cooling point.
When we were testing local series Supercar brake ducts some five or six years ago the difference in an inch spacing back from the centre of the rotor made over 100F temperature difference on the logger. It was from this data that the decision to run direct water cooling on the brakes of these cars was made. You can spend all the money in the world on carbon splitters and the like, the only track proven way of effectively and - measureably - cooling the brakes on the stock brake, stock front end GTR thats track proven is with water. Its the difference for us between having the pedal on the floor and being in the sandtrap after a handful of laps or having a 'second lap' braking feel the whole time
 
#31 ·
I will admit your a good salesman martin. But some people don't need water, just look at Darin, he uses spatulas with great results, brass monkey use ducts ducted to a plate and that's doing well for them, neoseven also using a home made duct system, nismo using a simple ducts on the splitter with air guide solution... I don't see any real need for water, and I'm unsure which races allow it anyways...

So I think there is plenty of evidence showing good results from this. Sure there is always going to be a few people that will push the car hard enough and be modified enough to need water solution(if allowed in the race). so I don't disagree with your solution, just think your sales pitch is a bit off, K&A would be happy tho.
 
#32 · (Edited by Moderator)
Mindless where are the results you speak of?
You should try actually driving a GTR at a track before you comment as to the effectiveness of the factory braking system. Its actually not great, particularly when using 18 inch rims to allow proper slick tyre selection. The brakes are a heavily compromised part of the GTRs track performance in this instance


What I can tell you from - actual real world engineering experience - is that brake cooling efficiency is inversely exponentially proportional to the gap between the duct and the centre of the rotor. Unless the duct is near touching the eye of the rotor there will be very little actual cooling effect. Its been this way forever, which is why proper race cars used sealed air ducts, as anything less doesnt really work with any great success. Now...try that on a GTR and get back to me when its done


While your constant insistance of trying to discredit anything we do with schoolyard logic is of some amusement to yourself and your supported vendors, it is generally quite tiresome to those that are interested in discussing the engineering merits of brake cooling solutions. Background noise down, facts up please. Thank you in advance
 
#33 ·
Downforce's solution is coming up- I have repeated this many times... but I swear, we're almost there!
 
#34 ·
Martin,

I have been to dozens and dozens of races with every kind of car imaginable. No one uses water cooling as the primary system. They all use brake ducts or deflectors with air to the rotor area. Some very well designed, and some less so.

Have you ever seen how Porsche designed brake cooling for the GT3 series cars, for the GT2, their Cup cars, and their road cars? All they use are scoops to direct air toward the brakes. Faster cars have bigger scoops. They are not within a mm of the center of the rotor, as they don't even have ducts. Are you saying their solution is improperly engineered and they should go with a Willall water spray system as that is the only thing that works? Porsche cars seem to be able to run all day on track.
 
#36 ·
I have been to dozens and dozens of races with every kind of car imaginable. No one uses water cooling as the primary system. They all use brake ducts or deflectors with air to the rotor area. Some very well designed, and some less so.
Obviously never been to a WRC race:

http://www.subaruwrcspares.com/2.html

WRC commonly uses water cooling. Most likely because it's allowed. Most series don't allow it because of safety concerns. In full wheel to wheel, it's another water reservoir and lines susceptible to rupture. In WRC this is not an issue.

Shawn
 
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