Identifying Brembo brakes

[jbourne]

So I got my hands on an RS6, and it came with yellow Brembo calipers. I'm trying to figure out what these are. It's using OEM rotors, but I'm confused as to why someone would replace the OEM calipers with yellow Brembo ones unless they got better stopping power. Any advice on what to look for? Is it possible the previous owner installed a better caliper kit but stuck to the OEM rotors, dumbly? (ie should I look at larger rotors maybe?)

As well, I wonder if OEM pads will fit on this, or do I need some other pads? Any way to determine without disassembling the whole thing? I suspect this is a Brembo GT set, but so too were the OEMs, no? So I'm confused why one would go through the hassle and insane expense.

Was there ever a Brembo GT factory option or are these definitively aftermarket?

[Per_S]

I'd say aftermarket for sure. The only option was carbon ceramic brakes.

[Jim Haseltine]

No accounting for taste. Maybe they're OE calipers refinished in yellow* with Brembo decals**.

* 'cos yellow = ceramics (sometimes)
** 'cos Brembos are an upgrade - aren't they?

[IanH755]

The OEM C6 RS6 calipers are made by Brembo. These look like someone has just refinished the OEM calipers to me as Jim said.

[Jim Haseltine]

Back in the 90s a mate had a Mk1 Golf project for which he sourced some Recaro seats (upgrades, aren't they, better than OE). Had to muck about cutting and welding subframes for the runners and then took the seats to be trimmed. When he was telling the trimmer what he wanted and why, the guy showed him a set of OE Golf seats he was working on - stamped on the frames was 'Recaro'.

[jbourne]

Took off the wheels today and looked at them more closely. They’re stamped Audi on some of the edges (in small writing), so I suspect refinishing them in yellow was what was actually done. Weird!!!! I guess they brake better in yellow?...

[IanH755]

Just a FYI, the OEM calipers really are fantastic and the same basic units (with different "car specific" mounting brackets) are used by the Nissan GTR, various AMG's etc. On the RS6 it's the crap OEM discs and the lack of adequate cooling which massively let the car down if you really push them hard.

I recommend that, at the very least, if you really want to push the car hard you swap the discs to AP Racing's OEM Replacement 390x36mm ones which are the same cost as OEM (maybe a little cheaper) but far out-perform the OEM disc. Using that AP Racing disc, Ferodo DS2500 discs and ATE Superblue Fluid I did nearly 50 stops from 160 to 10mph on the track without having any fade.

[jbourne]

Just a FYI, the OEM calipers really are fantastic and the same basic units (with different "car specific" mounting brackets) are used by the Nissan GTR, various AMG's etc. On the RS6 it's the crap OEM discs and the lack of adequate cooling which massively let the car down if you really push them hard.

I recommend that, at the very least, if you really want to push the car hard you swap the discs to AP Racing's OEM Replacement 390x36mm ones which are the same cost as OEM (maybe a little cheaper) but far out-perform the OEM disc. Using that AP Racing disc, Ferodo DS2500 discs and ATE Superblue Fluid I did nearly 50 stops from 160 to 10mph on the track without having any fade.

This is rather interesting as I always thought steel discs are more or less steel discs, though I've never driven a car this heavy and this powerful, so maybe there's a difference - on my previous 911, I focussed more on pads and caliper power than actual rotors themselves. Noted, though - I've heard AP mentioned a number of times, and I'm considering getting those, and I guess subsequent disc swaps would be cheaper as well. Just have to figure out how to get them out East... considering they're mostly Europe-based, it seems.

Incidentally, as I won't be tracking it in the first set of pads, I'm considering going with Brembo P50127 (front, looks like same pads as AMG G, Maybach and a few others) P85143 (rear, fits Bentley and some others) - and both _appear_ to be a fit to the RS6. Any thoughts on that?

[Jim Haseltine]

The cooling design of the OE discs isn't great especially with the holes tending to fill quickly with brake dust and other rubbish. As for the OE pads, their performance is well down to the low end of what is available - good enough for general road use but disappointing if you tend to drive in a push-on mode on routes with corners. For my driving I've found that a combination of OE discs and EBC Yellow Stuff pads are up to the task but am likely to be going for AP discs on the next disc change if I still own the car. As the distance I cover will drop significantly in 6 months time the next disc change could be some way in the future.

[don0301]

I have DS2500 pads now, but find them no different to OEM other than no pad wear connection *shrug*

One thing I WOULD recommend, which I'm amazed no-one has mentioned, is the "Phaeton mod" for standard sized discs. These are cooling "ducts" that fit the RS6 as if made for them.They cost about £100 (parts) plus fitting. Search on here for more details.

Make a considerable difference to initial "bite" and reduced brake fade.

I've been stage 2 about 5 years now, with standard setup other than uprated fluid,stainless lines, and the Pheaton mod. Have had no problem.

[jbourne]

Does the Phaeton mod work for AP discs too?

[don0301]

I don't know for sure, check the relevant "thickness" of each disc?

Don't see why not on the face of it.

The Pheaton mod replaces the OE brake back plate.

[Jim Haseltine]

It's the diameter that matters - a little. The Pheaton discs are a bit smaller than those on the RS so the disc shields are a tad small, leaving approx 5mm of the disc clear of the shield but as approx 2mm of that is pretty much unswept it's neither here nor there really. The AP discs are the same diameter as the OE so make no difference.

[IanH755]

Does the Phaeton mod work for AP discs too?

The Phaeton mod works with the AP discs no problem.

This is rather interesting as I always thought steel discs are more or less steel discs, though I've never driven a car this heavy and this powerful, so maybe there's a difference - on my previous 911, I focussed more on pads and caliper power than actual rotors themselves. Noted, though - I've heard AP mentioned a number of times, and I'm considering getting those, and I guess subsequent disc swaps would be cheaper as well. Just have to figure out how to get them out East... considering they're mostly Europe-based, it seems

OEM Vs AP Discs - The OEM discs internal "cooling veins" are not designed for maximum cooling as, to save costs, the discs are designed to be fitted to either Left or Right side, meaning that veins have to be straight, reducing the cooling effect dramatically. The AP discs are designed as Left or Right so the veins can now be curved to get maximum airflow from the centre to the edges, there are also lots more veins and the steel used is a much better quality steel, able to cope with the heat far better than the steel used in the OEM ones.

Now, if you're just road driving and only use 85-90% of the normal brakes you'll probably never had an issue. However, if you track the car or are extremely hard on the brakes at way above "spirited" driving levels, then that extra performance from the AP discs between 90-100% will be noticeable.

As an example of what I consider "hard" braking looks like, here's two images of my brakes and pads -

This is my AP 390mm discs (at the bottom - new 410mm AP discs at the top) after several track-days and about 20k miles of my own hard driving at 740hp and they are cooked! There's heat cracks all over, the metal is badly discoloured etc and they weren't even at minimum thicknesss yet. Compare them to the nice new discs above and thats how hard I use my brakes, if yours don't look like that then OEM will probably be fine and the AP's would be overkill.



This image is the state of the OEM pads which had the leading/trailing edges start to disintegrate after only a handful of hard road drives but NOT on a track. They couldn't cope with the heat I was creating and started to crumble away so much they almost looked like the cheap Textar pads you can get (definitely OEM pads), which is why I swapped to Ferodo DS2500's and never had that problem again. Once more, like with the discs, if your pads are fine already then there's no need to upgrade.

[jbourne]

Interesting. I definitely want to track the car, though potentially not in the first pad cycle (while I figure out the oil leak, I don't feel like I should be tracking it). So I might stick to Brembo pads first (the P/Ns I listed should work ... right?), but probably get something more serious for the next set.

If there's no major price difference between OEM rotors and APs, though, I think I'll just go AP and do the Phaeton mod. It seems illogical to cheap out on this!