Finally got parts required for S4 brake swap!

[B5QUAT]

Hi

After quite a few months scouring ebay and the small ads I have managed to gather together all the bits I need for my conversion of the brakes on my B5 1.8T Quattro to upgrade it to B6 S4 spec.

All the parts are hopefully being fitted tomorrow.

First on my shopping list was a set of B5 S4 uprights, which look like this:

I bought a set 2nd hand of SRS for about 130 quid if I remember. They were a bit manky and both wheel bearing were goosed but they came with 2 brand new ABS sensors. I cleaned them up and hammerited them and bought 2 new wheel bearing kits (about 30 quid each) ready for the transfer.

these are the painted uprights and this is one of the bearing kits

Finding 2nd hand B6 S4 calipers was a nightmare. I toyed with the idea of buying new (at around £150 each) but then you would also need to buy the carriers which are audi only and £150 each also. So looking at abill of 600 quid put me off and I decided to wait for 2nd hand. In the meantime I got some brand new 345mm B6 S4 front discs and pads. (around 45 quid a disc and about the same for pads from All German Parts in Leeds who are great)

Here is one of the discs with a 10p for scale and the pads too

Then finally I spotted some calipers (with carriers) on ebay which were in a set with the B6 S4 rear calipers (with carriers) also and front and rear part worn discs and pads. The back pads were FUBAR but the discs were great. So I bought the lot for just over 350 quid which gave me what would have cost me 600 quid new and I also got effectively free rear B6 S4 calipers and carriers (which I didn't need, so I sold on) and a spare set of front discs and pads and rear 300mm discs too! Bargain!

Tha calipers cleaned up well with a stiff brush and some detergent and once the crap and surface corrosion was wirebrushed off I painted them blue (just to be different!)

Here you see the front calipers and carriers separated. How Audi can charge 150 quid for what is essentially a lump of metal I don't know! I may upgrade the front brake hoses to braideds, but thought I would stick to OEM for now. I then got some rear caliper brackets from Trig off SRS and he also sent me some extended rear brake hoses as well for about 50 quid for the lot.

All I needed now was a set of B5 S4 facelift rear calipers which I finally sourced from the states (great cos less corrosion). They are en route to me now. So along with the 300mm back discs I have everything I need except rear pads which I will get when the calipers arrive.

rear calipers (which were £100) and back discs:

The fronts are being fitted tomorrow (along with DOT5.1 fluid) and the rears will be done as soon as the calipers arrive.

I should then have 345mm on the front and 300mm on the back instead of 288mm on the front and I think 240mm on the back so I would expect it to stop A LOT quicker!

 

[boost-addict]

looks real good so for £800 youve got much bigger brakes allround

isnt a 312mm conversion less? considering the ones you have are single pot also
and rears are 245 which i thinks more then enough if you have 300/312's up front

not putting a dampner on it all as youve got it all sorted new bearings etc but wondering if thats the long way round the houses?

 

[adamss24]

Way overkill for the b5 unless you're running 500-600 Bhp. 312mm would have been enough !

 

[B5QUAT]

looks real good so for £800 youve got much bigger brakes allround

isnt a 312mm conversion less? considering the ones you have are single pot also
and rears are 245 which i thinks more then enough if you have 300/312's up front

not putting a dampner on it all as youve got it all sorted new bearings etc but wondering if thats the long way round the houses?

Yeah know what you are saying. 312mm conversion would've been a lot less but I'm planning on a GT28RS conversion and well over 300bhp eventually and palnning on a few trackdays, so wanted excellent stoppers. They may be a little overkill but I also love the look of them. Saw a few cars at Inters last year with the huge B7 RS4 calipers on and they looked awesome. Wanted something similar for a fraction of the cost. I had AP Racing brakes on one of my old Subarus that was arouns 390bhp and it gives you tremendous confidence while driving fast having monster brakes.

 

[B5QUAT]

Way overkill for the b5 unless you're running 500-600 Bhp. 312mm would have been enough !

Don't agree, sorry. Audi put these on as standard on a car that although it weighs more has only 344bhp. Even the B5 RS4 with 380bhp has bigger brakes than these. For 500-600bhp I'd want something way beyond that. B7 RS4 stuff or similar.

 

[aragorn]

What you need to remember is the brakes are only as strong as the tyres.

I had my car out on track on saturday, with standard 288's, and was managing to get the ABS activating under heavy braking at times.

If the standard 288's are powerful enough to lock the wheels (ie activate the ABS) then some massive 345mm disks physically cant slow you down any faster, because your still limited by the tyres grip. Now yes, the 288's were marginal on track, and i would have benefited from larger brakes, but dont expect you can now stop in half the distance, because your still attached to the road with the same four squares of rubber. It would simply have meant i could have stayed out on track longer, rather than having to come in after 5 laps to let the car cool.

What larger brakes do give you is a bigger thermal mass, so they'll take the abuse for longer before chucking in the towel, and better pedal modulation due to reduced line pressures required to generate the torque required to lock the wheels, which makes it easier to control near the limit. This means that when you go out and test your new brakes, they'll stop harder with less pedal effort, giving the impression that they're many times better. In reality it just means you'll lock the wheels up pushing half as hard on the pedal.


What i'm intrigued by, is why you didnt just use the B6 rear calipers you had, instead you sold them and bought the B5 calipers and adaptors etc instead?

 

[B5QUAT]

I got told that I couldn't use the B6 calipers that I HAD to have B5 facelift ones. Please don't tell me I could've used the B6 ones! lol

I wanted to ask on here when I got them but at the time I was having problems posting on here. My computer wouldn't let me!

What you said is exactly what I wanted them for, not so much for stopping any quicker but to maintain their ability for longer periods, especially when I get to over 300bhp. I live near a lot of twisty B roads and I love nothing more than to hit the tops and give the car some sustained abuse, when your brakes start to boil, it's less fun, hence the 345's and 300's.

 

[aragorn]

Yeh you need a spacer and some fiddling with bolts and handbrake cables, but you could have used the B6 calipers!

 

[ScottD3]

Big Brakes

 

[B5QUAT]

Yeh you need a spacer and some fiddling with bolts and handbrake cables, but you could have used the B6 calipers!

******! I specifcally got told that the B6 was no good and I'd have to have B5 facelifts only. Oh well, you live and learn!

 

[adamss24]

Don't agree, sorry. Audi put these on as standard on a car that although it weighs more has only 344bhp. Even the B5 RS4 with 380bhp has bigger brakes than these. For 500-600bhp I'd want something way beyond that. B7 RS4 stuff or similar.

Listen man, Kev gave you a decent, reasonable explication above with regards bigger brakes, the b5 platform ABS/brake modulator is way too overservo-ed for such a light car. You should try 312mm new fronts/stock brakes all round then you come to preach me. Better pad choice is essential not the bigger size. I have had bigger 4 pot calipers on my b5 avant and rs4 rears and in the wet/snow the ABS was buzzing constantly. Yes, it would have stopped the car faster from a high speed motorway but only in the dry, as mentioned above you limited to the grip from the tyres.
The good thing with big discs is constant pad pressure along a wider part of the disc. I have now rs4 b7 front brakes to my allroad and it's not any different to what it was before. The only real benefit is lighter calipers which equates lower un-sprung weight on the front. They come at a price though and i dread the time of replacing !

 

[boost-addict]

so in essence, if ive read right, theres no point in going from 288's to 300/312's and is just a waste of money unless you plan to be driving hard 80% of the time or get alot of track time?

 

[ScottD3]

so in essence, if ive read right, theres no point in going from 288's to 300/312's and is just a waste of money unless you plan to be driving hard 80% of the time or get alot of track time?

Don't forget though, bigger brakes looking fkn cool!!



Not everything has to be about handling or performance gain, surly?

 

[boost-addict]

thats true. big fat porsche brembos sat behind some nice rims look good, but for £800+ quid id would rather have spent all that money else were. or at least just upgraded to 312's which is the most easiest way of doing things.

but there you are at least hes now ready for anything!

 

[aragorn]

yeh i think for most mildly tuned road cars, a set of 312's and GOOD pads would be plenty.

I dont think you can say you've got "too much" braking, but the gains from the expense are somewhat deminishing returns, unless you have a LOT of power or use the car on track.

One thing you will find with a rigid multi-piston caliper like a porsche brembo, is a much more progressive pedal. The standard sliding calipers flex and bend, which makes the brakes a bit spongey. The solid 4pot caliper gets rid of this, giving a more confidence inspiring feel to the brakes.

 

[B5QUAT]

ARGH! Beginning to wish I'd gone the 312mm route now. MY ****** wheels won't fit over the calipers now!

Going to need a 10-15mm spacer.

This just gets worse.