Brembo GT-R as a solution to B8 brake heat

B8 S4
#101

Yeah…while I like what Psychotic did, it makes oil changes a hassle since the under panel has to be removed for fluid changes…that means re-ducting each time (possibly). I’d rather go ghetto and cut like, a 2L coke bottle and zip tie it to the LCA to guide air to the rotor or something :smiley:

I also ran the Pagid endurance pads (yellows…RS29 and RS19) before. They are wonderful!
Sadly, they only make the RS19 for the stock caliper. I don’t think RS19 is going to be sufficient for any real braking on this fat piggy.

#102

No issues with RS19 on the rear. They barely wear down, which shows how little braking they actually do. I hope my stiff rear springs and dampers encourage some rear brake participation this season. Temps on the rears are a solid 250F lower than front.

I was running Pagid RS29 front but have switched to the Brembo equivalent endurance pad, called the RE10.

#103

Agree with RS19 in the rear–that’s actually that they were designed for.
Totally fine out back. But unfortunately, RS29 isnt made for the stock front caliper…so what I meant was that if one were to run RS19’s all around, it may not be sufficient for any real usage. Were your RS29/19s really loud too?

I ran them on 4 piston floating front calipers + sliding rears, and they were craaaaaaaaazy loud. They would bed in, but would become unbedded with city driving and it’d just be nuts.

#104

The RS29 on a Stillen AP Racing rotor was dead quiet on the street. At worst it had a sound like a plate being dragged over concrete.

The new Brembo setup has some brake squeal. We won’t really know until Monday, when I’m done putting 100 laps on it :slight_smile:

#105

Early track impressions:

This car has more braking power than god himself. I can adjust my braking points by about 2 car lengths once I get comfortable. I’m happy to say the rear brakes are now participating in my track days, where before they were just along for the ride.

Coming off a hot track the fronts were very cool at 450F, whereas the rears were a bit hot at 600F. With the AP Racing kit and OEM suspension I’d see 750 F front and 450 F rear.

So I’m expecting to have to replace the rears maybe every 18 months. They get quite hot. The good part is the wave rotors are actually functional. At the edges the disc was a mere 300 degrees. The hot temp was only the inside edge. So maybe they won’t crack. The cast holes and dimples are not functional at all. They completely filled in with brake pad material and dust.

Edit: 650 F front and 700 F rear after a more aggressive session.

#106

The rear RS5 rotors are not directionally vaned I believe? The JHM rotors are. The vanes play a huge roll in the heat dissipation. I bet they don’t crack as easily as the JHM’s due to the semi-floating setup. You are definitely heating them up a lot.

Would be curious about your delta’s from left to right on temps. They will be influenced by the track in terms of right/left turns and how much trail braking you do. But I believe the vaning is correct for one side and backwards for the other, so you might see some variation. This is using your IR heat meter, correct? What is the precision of these meters? Do you ever use the little stickers on the caliper?

Are you using the same pads in the rear as before (pagid)? Also is this your first real track day on the cup tires? Your friction circle should be quite a bit larger, especially after getting the tire temps up.

Sounds like you are getting to battle test some of be best kit on the market. Looking forward to your reviews on how everything performed.

#107

RS19 on the rear still. Left to right temps were fairly even, and when they differed it was not consistent. Sometimes left was 8% hotter, sometimes right was 8% hotter (40 degrees F).

I’m thinking about removing the fog lights. On the passenger side I can put a piece of 2.5" tubing to route some air into the wheel well. On the driver’s side it’ll simply let more air hit the heat exchanger. My driver’s side wheel well fabric is all blown out from the rain going through that heat exchanger anyway. Effectively air is traveling through the valence onto (and behind) the wheel. I have to take some shears and cut it away more cleanly.

#108

wonder if you can adapt these to the b8

http://www.audiworld.com/tech/pics/wheel60_12.jpg

http://www.audiworld.com/tech/wheel60.shtml

there is a guy on QW gription, i believe he is close to you in norcal that was running some nasa brake ducts routed to the front grill.

http://i303.photobucket.com/albums/nn125/wsteineke/P1210229.jpg

http://i303.photobucket.com/albums/nn125/wsteineke/P1210183.jpg

http://forums.quattroworld.com/s4b8/threads/2644.phtml

#109

They’re running pretty cool. I don’t need air directly on the rotor. Just piping it into the wheel well with a ram air effect would be sufficient to allow for a shorter cool down lap.

#110

Clean daylight shot with the RS5 wave rotors and the brembos in front

http://i58.tinypic.com/a11jyu.jpg

#111

Is it me or are the tires smaller diameter than stock?

Oh and have you considered simply removing the splash shield behind the rotors?
That alone will help greatly with brake heat. I am pulling mine off.

That, along with brass bushings for the slider pins on the caliper.

#112

he’s actually in chicago and had chicago performance & tuning do the duct work. really nice guy - met him at a road course event.

#113

25.5 instead of 26.0.

#114

I recently installed a Stoptech Trophy 380mm BBK and rear Stoptech Sport rotors and finally decided to ditch the splash shields front and rear. After staring at them during the install and realizing the rotors sucked air in from the area the splash shields were blocking I couldn’t help myself. I head to the track in early April and can’t wait to try my new brakes out. I’ll be running Pagid RS-29 front pads and Stoptech Street Performance pads in the rear. Rotors are all slotted. And I’m running the stock suspension still so expecting the rear to hold up despite the subpar (for the track) pads.

#115

Good call on taking the dust shields off.

It should help cooling. :slight_smile:

#116

I should add this brake setup survived Laguna Seca, which is the proving ground I originally bought them for. Turn 2 is a downhill at the end of a straight that routinely destroys brake setups. With the Brembo GT-R on front, RS5 wave rotors on the rear, a stiff rear spring, and Pilot Sport Cup 2 all around I had zero issues with doing a dozen sub 1:50 laps in a row. The braking was the same in the 2nd lap as the 12th, which is pretty incredible. It wasn’t cheap to get there but it’s safe.

#117

Out of curiosity, do you double apex that turn (treating it as a single turn - holding the wheel to hit both apex) or treat it as two separate corners (tracking out after apexing the first and coming back in)?

I was experimenting when I was there and the double apex approach worked better for me/my car.

#118

Single apex. Let me explain:

In the approach to turn 1, I bring my car all the way to the left like I want to clip the bridge support. Then the car wanders to track middle at the top of the hill where I am still flat out. A gentle nudge left for turn 1 has me clipping the white paint (rain runoff) of the track entry zone. Then I straighten the car out for the last 1/4 of the downhill and brake at track middle.

I extend the braking zone almost to the white line, get the car to change direction, and at that exact moment throttle steer through the curbing on the left adding judiciously until it lands me in the curbing on the right. Now the car is pointed at turn 3 and I’m full throttle aiming for it.

#119

Got it, so you go wide and deep and don’t even touch the first apex (and instead “late apex” to hit the second set of curbing). I think that’s the school line too.

My approach is the same as yours right up until braking. I get really close to the bridge support (lol great pics from the photographer too) and aim for one of the wooden telephone/electric poles to see me through the crest (I want to say the middle one - it’s more muscle memory from the two days I was there). From there, I track out 2/3rds of the way right, shave off a bit of speed, and then line up the car for the first apex (when the brake markers are done) and brake hard in a straight line and pivot/rotate the car when the front driver side wheel hits the rumbles. Holding the wheel will double apex the corner for me (with appropriate throttle steering). The RS5 seems to complain less when I do it that way (if not, I feel the front inner wheel braking to stabilize the car - something I’m actively trying to avoid - mainly to manage brake temperatures).

Man, I really, really miss that track… I want to go back so bad…

#120

not sure if others saw these, but ecs makes a 2 piece floating wave rotor for the rear and fronts now. Much cheaper than the oem setup. http://www.ecstuning.com/Audi-B8_S4-Quattro-3.0T/Braking/Rotors/ES2681109/