Best Brakes for A3 S3 guide

As some of you know I've been doing some brake investigations and I think I've pretty much found the best setup for A3/S3's.

I've spent a LOT of money to finally come to a brake setup I think is more than adequate, so far I have tried:

Discs:
Audi OEM Discs
EBC Turbo Groove Discs
Mintex
Zimmerman Solid
Black Diamond Grooved
ATE Power Discs

Pads:
OEM (Textar)
EBC Green Stuff
EBC Red Stuff
EBC Yellow Stuff
Pagid FR
Mintex Extreme
Ferodo DS2500
Ferodo DS3000

There may actually be more, I cant remember it all, I've had a lot!

I have the standard 312mm setup in regards to calipers, and my car is probably 150-200kg lighter than you guys, but the following info is still very relevant due to the power I am running.

Lets start with the actual braking hardware, and compare Brembos to the standard 312mm brakes.

The Brembo GT two piece calipers are a similar weight (although are lighter) than the stock 312mm calipers. They are also 4 piston calipers and thus better/more efficient than the sliding caliper (equivalent to 2 pistons) standard caliper.

However, there is one major downside to the Brembo GT system = weight. The GT discs are 323mmx28mm compared to the 312mmx25mm standard discs.

The Brembo GT discs weigh a LOT, I havent actually weighed them for exact figures but holding them up side by side there is a huge difference, probably somewhere in the region of 1.5-2kg. (Much wider, taller discs on the Brembo is a lot of extra metal)

The big disadvantage there is in unsprung weight, as adding 1kg of extra unsprung weight is the equivalent of adding 6kg of sprung weight, plus it is detrimental to handling/cornering/suspension.

Aside from this Brembo discs are pretty famous for warping so cost is a factor considering ideally you should throw away the drilled discs and buy Leon Cupra solids.

That said, they brake very very well even on standard pads

However, for this I am going to discount them on the basis that they arent needed for anything but big turbos, they cost a lot to buy, they cost a lot to replace discs and they are detrimental to the handling of your car.

So, the cheapest and generally most sensible choice is
to retain the standard 312m setup and make it the best it can be.

The first thing you need to do is change your fluid. After only one year your fluid can take on as much water as 3%, which actually translates to 15-25% less braking power!!!!

The type of fluid is important too, as DOT5.1 fluid with 3% water still performs as well as brand new DOT3 fluid.

So you ideally want to use DOT5.1 as its more resistant to water, and has higher and lower boiling points.

This is one of the things that makes brakes fade, boiling fluid, the fluid boils due to heat and the boiling produces steam, which then cools to air and water, which then gets into the system making for a spongy brake pedal.

So you also need to try and use a fluid which has the highest possible wet and dry boiling points.

You have three choices:

Halfords DOT5.1 - Cheap with a trade card (3 per bottle)
Motul RBF600 - 11 per bottle and excellent properties
Castrol SRF - The best of the lot but 40 per bottle.

So if you dont mind changing it often and have a Halfords trade card, the Halfords stuff is great.

Castrol is VERY expensive so that leaves Motul RBF600. It is actually classified as a DOT4, but everything except viscosity at 40 degrees is better than DOT5.1 and its cheap at around 10-12 a bottle so well worth using.

So first thing, make sure you fluid is new, and good quality, such as Motul RBF600 Factory line.


Right, now onto discs, these are less complicated, all discs are is a friction surface for the pads to act against, so they are the least important parts of a setup.

For heat dissipation and price, any solid discs such as Zimmerman/Mintex whatever would be great, and cheap at under 40 pound each.

Grooved discs have slightly more cooling area than solids due to more surface area and they also serve to slightly deglaze the pads (although this is less important when using better pads but I'll come to that).

Drilled discs are the devils work, they are actually nothing to do with heat dissipation and all to do with reducing weight, which is why you see drilled discs on cars with huge brake discs, its to reduce the unsprung weight. However, on cheap discs it also provides a heat concentration point and it tends to warp and crack the discs.

Another important factor is how the discs are treated, their carbon content etc, but the idea is, the more you pay for a set, the longer they will last.

Black Diamonds are a good example of this, they last forever and a day, where the BD had 10K miles and were 1mm down from new, the Zimmermans had 5K and were 1mm down from new.

So, fluid is very important, discs less so, now onto pads.

Pads these days vary in quality a huge amount, right from 30 pound OEM pads to 160 pound DS3000s.

The most important thing to remember with pads is, you get what you pay for.

ALL EBC pads are rubbish, utter, utter rubbish and I wouldnt wish them on anyone. They have slightly better properties than OEM when warm, but otherwise are way worse. (With the exception of yellows, which are better than OEM at all times but awful compared to other track pads)

OEM, Pagid FR and Textar pads all seem to be very very similar, or at least made to similar specs. Pagids again have better fade resistance than OEM but the same friction properties in general. They would be a good choice if only wanting something cheap but better than OEM.

Mintex Extreme are very good, they are far superior than OEM from Cold, have great, repeatable friction and it takes some work to get them to fade. They are however, discontinued.

Now onto the Ferodos. These are the pads to end all pads. There are a few better for certain applications but very little will touch these two for road and track use.

Firstly Ferodo DS2500s. They have better bite from cold than OEM, better bite hot, never EVER fade and have a really consistent friction co-efficient of 0.48 from cold right to about 500 degrees.

These make OEM pads look like you've been using compacted paper as pads, they are a world apart.

They cost about 130 the pair and are well worth the money.

Now until about a week ago, I would have ended there, but as it happens Bill at Badger5 supplied me with some Ferodo DS3000s and I fitted them the day they arrived.

The difference between DS2500 and DS3000 is like the difference between OEM and DS2500 - its HUGE.

DS3000 are 160 the pair, but I absolutely will never use DS2500s again.

The friction co-efficient of the DS3000s is better (0.62) and again is the same, repeatable throught the temperature range. Basically your fluid will boil before the pads suffer fade, they are THAT good!

They do suffer badly from squeal at low speeds and when cold, they also need a little bit of heat to work (they are race pads) but they absolutely stop the car dead.

Prawn from this forum drove my car yesterday, we have pretty much the same car but he has Black Diamond discs and Ferodo DS2500 pads. He got out of my car and proclaimed that they are 'shockingly' good, and hes right.

The tyres loose traction if you brake too hard with DS3000s (Goodyear Eagle F1s) and on continued braking they just keep braking exactly the same regardless of heat, doing some country back roads they were the same from start to finish.


To finish off, the other thing you should look at is replacing your brake hoses if you have a lot of miles on them. The standard Audi hoses are internally braided but also very large bore, so replacing them with small bore braided hoses means less effort - same braking = better pedal feel.

So, for the BEST system for 99% of S3s you would need:

Braided hoses
Motul RBF600 Fluid
Discs of your choice (ATE Powerdiscs for me)
Ferodo DS3000 pads.

P.S For the rears, they do very little braking so even OEM pads will be fine, and OEM or Brembo Max discs (Solids).

Brembo GT - New 800, but lets imagine you buy a set secondhand, so 450.

Next time you need discs its 250 per pair for solids and 90 for the cheapest decent pads (DS2500)

However, if you have 312mm and Ferodo DS3000s then its 120 for the discs and 160 for the pads. 40 if you dont already have braided hoses.

So Brembo GT kits are heavier and can affect handling, cost more and the pads that come with them are not even 50% as good as DS3000s.

Brembo GT set with DS3000s would be the way to go for big turbo cars, but you absolutely dont need to spend that much and the 312mm kit above is BETTER than the braking provided by brand new standard Brembos.
(For track work and very fast road, I doubt anyone would notice any difference day to day)

I type fast

Putting the same friction material in the rear will produce a rear bias on a FWD car and it'll handle like cack on a track.

Ferodo DS pads (not DS2500 or DS3000) will be OK, but having the same material front an rear is a BIG no no

I have experience

On what basis? They have a friction co-efficient of 0.58-0.60 whereas Ferodo DS3000s have a friction co-efficient of 0.62.

They should be better than Ferodo DS or Ferodo DS2500 but they are NOT better than Ferodo DS3000 pads.

They are however, cheaper and not far off the Ferodo characteristics. (For Brembos, you cant get them for 312mm S3 calipers)

One of the only similar priced pads that you can get that are as good as the DS3000s are made by Performance Friction.

Less dust would be a definate positive.

But tell me again why you'd go to the trouble of getting some Carbotech pads made up to your own backing plates when their material doesnt have a friction co-efficient as high as off the shelf DS3000s?

jojo - I have experience with both, and believe me, DS3000s on the 312mm setup will make your Brembos look very silly indeed.

Stick DS2500s or DS3000s in the Brembo calipers and theres a different world of braking, but standard Brembo pads (made by Textar) are nothing compared to DS3000s

A couple of people are asking about if I meant road/track...

I wrote it in the mindset of my use, which is daily driver and occasional track use.

The DS3000s have a 'constant' friction co-efficient of 0.62, so when I say not that good cold, I mean the very first stop of the day, like the stop you do at the end of your street before turning onto the main road. After that, they are 100%.

However, they can be noisy at low speeds, which DS2500 are not.

DS3000s also produce more dust than DS2500.

Regardless, the DS3000s are SO much better than DS2500 I would be hard
pushed to think of a situation where I would rather have the DS2500 than the DS3000.

This is why I say they are the 'Best'.

On another note, please dont anyone think that I am saying the above system is 'better' than a Brembo GT kit. Brembo kits are excellent. But you do have to remember a few key things about Brembo kits.

They are very expensive for what they are, which is a very old two piece brembo design that doesnt even come on the cheapest porsche these days. The discs are expensive to replace and warp easily (although buy solids and problem solved)

They add a lot of unsprung weight, roughly the equivalent of 48kg sprung weight (1:6 ratio) so your handling will be ever so slightly affected.

The standard pads supplied with the brembo kit are made by Textar, they have a much lower friction co-efficient than a lot of quality pads.

So, to make a Brembo GT kit 'really good' you're going to need to have 2 piece discs and bells, and use Ferodo DSxxxx pads, along with a decent fluid.

This essentially takes the price for the initial buy up to 1500 pounds which is a LOT of money considering how cheap decent 312mm sets are and the 312mm system is proportionately more than enough for most S3 drivers as most dont have big turbos or spend their lives on track days.

Not only this, if you want a GOOD big brake sytem you would have bought an AP Racing kit anyway

That was the difference between the standard set and what I've listed above as a good set. Co-incidentally, the lesser price with two piece discs was for the smaller Ibiza Cupra R set.

But yeah, you cant get the kit without the standard pads and good pads are £130

Then add the Castrol SRF at 40 per litre

and your two piece discs, they are easily 500 for proper ones.

The math is correct.

S3Rav - changing the rear discs and putting on a higher friction compound than the fronts will cause rear bias and it'll drive terribly, the back will constantly try and overtake the front under heavy braking - dont do it!! Putting OEM on the rears, or making sure the fronts has better friction material and you'll be fine though.

S3Ren - Yeah you could jsut change pads/fluid and it'd take little longer to bed in but be fine with the OEM discs.

Just do the rears now with OEM parts/pads.

Do the fronts later with the decent stuff....

The S3 is a FWD car to all intents and purposes, it is only AWD when the Haldex is in operation, which only happens when the fronts lose traction.

So you should adopt the FWD basis for compounds on the S3 to be on the safe side?

scib4 - Whats talking mince? gay talk? Either way, I talk with a lot more knowledge on the braking systems of this chassis than you do.....

Please do enlighten me with your advanced knowldge of the chassis then? And why its vastly different to either an A3, or a TT or a VW 4 motion?

And whilst we are at it, explain again why Carbotech pads with a friction co-efficient of 0.58-0.60 are better than Ferodo DS3000s with a co-efficient of 0.62..................................

Very very VERY true

Brembos look the business. Especially in red.

Because the rolling intertia of the S3 is about 200kg heavier, using the same braking system. However, due to the 70/30 split and the S3 having 256mm vented rears instead of 239mm solid discs means the actual braking effort needing to be imparted on the cars front axle is nearly exactly the same.


Do most cars do short trips? I know mine does, my work is only 6 miles away, however due to the CONSTANT friction co-efficient of DS3000s the very first stop of the day, the 10mph-0 as i get to the t-junction 20 yards from my house is not as good as when I re-apply 50 lards later turning left. However, that stopping is still better than OEM pads. I believe I did mention this earlier.

You can only have tried both Carbotechs and DS3000s in Brembos, whic makes your point invalid as the discussion is about the 312mm setup. The actual figures prove you wrong again, as the friction coefficient is higher with Ferodo pads.

You would buy RBF600 over and above RBF660 for two reasons: Firstly price, at £11 per bottle for 600 its cheaper by a long way, and as my discussion relates to road and track use, as opposed to track only, the extra money saved buying 600 is worthwhile. Even Bill brockbank in his 500Bhp Ibiza rates RBF600 so you would assume its plenty good enough for occasional track use.
Secondly, the RBF600 is a DOT4 fluid that exceeds DOT5.1 fluid specificatiosn except viscosity at 40 degrees. RBF660 is a DOT5.1 fluid.
DOT 5.1 is more compressible than DOT4, hence you get a firmer pedal feel with DOT4.

You can get a CHEAP set of Brembos with two piece discs for very little money, but then I started specifically referencing a 'ultimate' set which would have Ferdodo pads and two piece discs. The same as you can buy 312mm discs for £30 (Eicher) or £170 (Black Diamond) there is also a massive margin of differences hence the price differences oultined in previous posts.

I got my specs from the Carbotech website, I think it was the AU website....

Well, your 1100kg 306 experience is about as relevant as a medal in pickled onion monster munch eating isnt it.

How is the brake bias setup, what distance are the pads and what what angle are they located from the inner disc face?

They are totally incomparable.

I buy RBF600 for £9 per bottle, the RBF660 was closer to £15 when I check, so thats 1/3rd the price more. Opie Oils and the like are more expensive at £11 per bottle but then you would imagine the same price differential should they start to stock RBF660. You cannot account for future developments, my information is based on what is available NOW.

Google Carbotech XP8 friction co-efficient, there are literally hundreds of webpages showing specs, here is one:

http://www.ricks2k.com/products/Carbotech.php


I suggest you read up on friction co-efficient before bringing a knive to a gunfight, so far, you've brought nothing worthwhile to the topic and added nothing of merit.