S3/R32/Cupra 2 brake upgrade

[Teutonic_Tamer]

Nice info :thumbsup: thanks for sharing . Bob.G

Here the link for people experience the O.P. is having

http://www.golfgtiforum.co.uk/index.php?topic=93993.0

Hey, my thread has found its way across the pond! :23:

 

[Teutonic_Tamer]

If anyone doesn't like painting the blue R32 calipers, then the latest Seat Leon Cupra also uses the identical 345x30 front brakes, but are already painted red - and match the OEM GTI colour. Details below

Last week I've installed the S3/R32/Cupra 2 front brakes on my '05 GTI. The parts required for this are :

- brake caliper left blue > 1K0 615 123 G
- brake caliper right blue > 1K0 615 124 G
- caliper carrier blue > 1K0 615 125 F
- retaining spring > 4F0 615 269
- brake disc ventilated 345x30 5/112 > 1K0 615 301 M
- splash shield for brake disc left > 1K0 615 311 C
- splash shield for brake disc right > 1K0 615 312 C
- brake pads with wear indicator > 1K0 698 151 B
- hexagonal head bolt M8x12 > N 907 186 02
- brake hose > 1K0 611 701 N
- brake pipe hose from brake hose to piston housing left > 1K0 611 763 A
- brake pipe hose from brake hose to piston housing right > 1K0 611 764 A
- retaining clip > 191 611 715
- bracket for brake hose left > 1K0 611 841 A
- bracket for brake hose right > 1K0 611 842 A

- brake caliper left red > 1K0 615 123 K
- brake caliper right red > 1K0 615 124 K
- caliper carrier red > 1K0 615 125 G

I don't know how easy these will be available in the US or Canada, but they are freely available in the UK and Europe. I guess they are also available in South Africa and Mexico too.

 

[Teutonic_Tamer]

MkV GTI front brake is called "FN3(16)", which disk is 12.3inch(t=25mm), it fits 16" wheel minimum.

MkV R32 is called "FNR-G(17)", 13.6inch(t=30mm), and it 17" wheel minimum.

But that uses an "American" terminology to describe brake dimensions - which is factually incorrect and confusing.

The Mk5 GTI has a 312mm diameter disc, which, as you correctly state, equals 12.3 inches. And the R32s discs are 345mm diameter (about 13.6 inches).

The size of the actual roadwheels required, whilst being important, is actually a very misleading way to describe brake sizes - particularly as most aftermarket wheels have differing clearances compared to the standard OEM wheels. This then also leads to confusion in the quoted Ross-Tech Wiki article.

I've seen the mention of 16" somewhere under ABS in Vag. They tried several codes there but everyone of them was throwing some fault codes. They also say about firmware in ABS not accepting the new brakes or wiring differences (bridge or ground connection) >

T47/14 <> T47/38 = PR-1ZF/1ZM/1ZC (15")
T47/12 <> T47/38 = PR-1LJ/1LL/1ZE/1ZD/1ZP (15" & 16")
T47/14 <> T47/39 = PR-1LK/1LM (17")

Now, I'm not an expert with vag-com and nor an electrician but from what I understand, I should change some pins in the ABS sensor connector !? Even so, I never worked with pins so I don't quite know what T47/12<>T47/39 means (this is the one i should have with the new brakes) !

Those above deal with the differing requirements for the electronically controlled brake bias (commonly called "Electronic Brakeforce Distribution" or EBD). This is due not only to the increasing diameters of the actual brake discs (which make them more efficient for the same applied force), but also, and more importantly, that the different calipers have different diameter pistons, therefore differing surface areas within the hydraulic circuit.

Some sources state that just a simple coding change in VAG-COM is required, whereas other sources state that electrical contact pins need swapping on the main connector to the ABS/ESP modulator.

 

[Teutonic_Tamer]

Today I've also drove an Audi A4 with 2.5L engine. It had the same calipers and discs as S3/cupra/R32 but its brakes were weaker than mine so I'm somewhere between S3 and A4.

A couple of crucial differences, though. The A4 will be quite a bit heavier than the S3/GTI/R32, and also its weight distribution is much closer to 50:50 distribution compared to a GTI - so not only will the brake bias be slightly different, but the brakes will have to work harder to cope with the extra mass.

The other crucial difference though is the actuall calipers. Whilst the Cupra/S3/R32, and the larger Audi A4/S4/A6 all share the same fundamental design of ATE FNRG caliper, the Cupra/S3/R32 has a 57mm diameter piston, whereas the Audi A4/S4/A6 has a 60mm diameter piston - which will again make a difference.

 

[Teutonic_Tamer]

I'm interested as well to upgrade the front brakes of my A3 8P 2.0 TFSI and i thought R32/CUPRA/A3 3.2 and S3 brakes were the same but if you look close at the pictures below, you will notice some différence betwen them.

S3 Brakes

The S3 brakes are identical to the R32 and Cupra brakes - with the very obvious change in the colour of the paint. What you seem to have a concern with is the different caliper retaining spring - the Cupra and R32 use a plain unpainted spring, whereas the S3 (and S4) use a painted spring with the model logo. So if you fancied black calipers on a normal A3, get the S3 caliper housings and carriers, but get the plain springs from the Cupra or R32.

EDIT: Whoops, the above had already been answered!

Huh - why are those ECS ones missing the crucial caliper spring? :mad0259:

 

[Teutonic_Tamer]

less mass = faster heat soak

For a simplistic view, I would agree. However, many quality aftermarket brake upgrades from the likes of Alcon, AP Racing or Brembo can offer improved brake performance from much lighter brake discs. The crucial issue for preventing "heat soak" is simply down to the quality of the design, and therefore the efficiency, of the intregral ventilation ribs.

drilled = cracked rotor

Only on cheap poor quality drilled discs. On OEM drilled discs, such as the Audi RS4, or quality aftermarket drilled discs - where the drillings are correctly chamfered, then you will NOT suffer with cracked discs (unless they are blatantly abused).

Drilled discs, correctly engineered, DO offer noticeable advantages, particularly with reducing or limiting brake fade, by allowing the gasses to vent from the pad surface to the central ventilation areas of the disc.

slotted = faster wear on pads

Fully agreed. And slotted discs make more noise too.

drilled = hissing noise every time you brake

Again, only partially agree. On poor quality or cheap discs, then yes, they may make a hissing noise. However, for correctly engineered quality OEM or aftermarket drilled discs, the pitch of the drilled holes should vary (just like the pitch of the tread on tyres), and this not only eliminates any hissing noise, but actually helps reduce general brake squeal.

drilled or slotted = more expensive

Not necessarily. I guess you could get some cheap drilled/slotted discs cheaper than say an equivalent plain disc from AP Racing.

 

[dustinwark]

subscribed

 

[etang789]

If anyone doesn't like painting the blue R32 calipers, then the latest Seat Leon Cupra also uses the identical 345x30 front brakes, but are already painted red - and match the OEM GTI colour. Details below



- brake caliper left red > 1K0 615 123 K
- brake caliper right red > 1K0 615 124 K
- caliper carrier red > 1K0 615 125 G

I don't know how easy these will be available in the US or Canada, but they are freely available in the UK and Europe. I guess they are also available in South Africa and Mexico too.

Do you have any UK or european website that you recommend? I am located in Hong Kong, and would like to order these in red for front and rear!

 

[-h2n-]

OK.

I've pulled the trigger on the R32 brake upgrade.

Managed to consolidate most of my parts with those posted on here except for one piece which is puzzling me. Can someone please shed some light on what this piece is and what it does? Please refer to the pic attached below

Thanks!

 

[VW_MKV]

OK.

I've pulled the trigger on the R32 brake upgrade.

Managed to consolidate most of my parts with those posted on here except for one piece which is puzzling me. Can someone please shed some light on what this piece is and what it does? Please refer to the pic attached below

Thanks!

u are kidding me right? Take a look at the pics posted on page one, threre is a pic that shows the back of the caliper with the brakes hose, bracket and that metal pipe connected to the caliper. Maybe u should have someone do the install for u.....:eyebulge:

I am running front and rear r32 brakes and its such improvement over stock.

 

[-h2n-]

love this site. a reply in one minute.

excuse my ignorance. i admit to being a noob but i'm still learning so please bear with me.

i just couldn't see that piece when i took off the caliper. it should be visible from the back of the caliper no? (refer to pic below) is it possible to run the brakes without this item?

thx again!

 

[jakethemoss]

Subscribed

 

[Dan GSR]

is it possible to run the brakes without this item?

thx again!

sure if you get custom made brake lines as r32 length lines will be WAY too short
and don't mind the line rubbing against the axle or tire

 

[-h2n-]

sure if you get custom made brake lines as r32 length lines will be WAY too short
and don't mind the line rubbing against the axle or tire

i'm using Goodridge SSBH that were on there when i had my stock GTI brakes on. they seem to work fine, just had to use a different sized bolt to attach it to the caliper body.

does that make sense?

 

[Dan GSR]

i can't visualize it working well
pics?