S2 Coupe Rear Brake Upgrade ?

[v|ncenT^]

Hello..

I need to upgrade the brakes on my '93 S2 ABY..

What is the best solution for the rear axle ?
Hoping for a caliper that have the handbrake mechanism, and a disc that keep the ABS function in operating condition..

What gives the most for the money, and are a straigt swap ?

Thanks for good solutions

[ericd]

Hello..

I need to upgrade the brakes on my '93 S2 ABY..

What is the best solution for the rear axle ?
Hoping for a caliper that have the handbrake mechanism, and a disc that keep the ABS function in operating condition..

What gives the most for the money, and are a straigt swap ?

Thanks for good solutions

use the search function, it's your friend

[v|ncenT^]

Tried it, did'nt find any easy solutions

[ericd]

Tried it, did'nt find any easy solutions

You didn't mention easy, try this...

http://www.s2forum.com/forum/showthread.php?t=13798

[Greg_S]

an intermediat solution is braided hoses, red stuff pads and dimpled disks

[S2central.net]

You didn't mention easy, try this...

http://www.s2forum.com/forum/showthread.php?t=13798

Its easy enough - just not cheap unless you can source calipers and carriers 2nd hand. Bolts straight on (after the disc is reduced to size on a lathe) with the help of some bracket spacers. Absolutely no handbrake problems.

[HPmuirt]

an intermediat solution is braided hoses, red stuff pads and dimpled disks

I agree with the braided hoses, but red stuff pads are pointless on the rear, since they are next to useless cold and the rear brakes will simply never heat up and maintain the correct temp for reds....quite apart from the fact that EBC redstuff is best avoided in general.

Also whilst dimpled holes cause less cracking than straight cut holes, they are still pointless, especially at the rear, since modern pads hardly gas on the front (where 70% of the braking is done) let alone the cooler rears, so you are simply giving up 5% braking surface for no benefit.

Remember that the main reason for running bigger disks is increased heat dissipation. Prolonged over-heating causes the disks and pads to run above their optimum frictional efficiency, thus loosing braking performance. Also, it causes heat soak in other components where it is most unwelcome. Calipers running too hot cause the fluid to boil and degrade, plus eventually the heat reduces the lubrication in the wheel bearings, leading to bearing failure. I am not convinced that even moderate track sessions can cause any of this with well maintained stock rears, so why upgrade?

The downside of running bigger brakes is an increase in the unsprung mass and also the rotational mass, so again, pointless upgrading the discs to monster proportions all round, if you never race the car....it is basically all for show, so why upgrade?

I really like Paul's solution for larger rear brakes, but unless you are running serious power and using it all...regularly, then I am not sure that you will see much benefit from upgrading the rears when running the monoblocks at the front. I think the brake bias with the standard rears and front monos is very good, so unless running Ben stylie RS4 fronts I would simply runs good pads and braided lines at the back on standard disks and use ATE racing fluid - changed yearly.

A final comment would be that decent suspension and tyres will dramatically increase braking performance far more than spending £100's on rear brakes ever will.

Cheers n

Si

[LHD_Kid]

A final comment would be that decent suspension and tyres will dramatically increase braking performance far more than spending £100's on rear brakes ever will.

Yes, I really agree with all of this post, and this part in particular, plus you obviously get much, much better general handling as well...

[Crawford_S2]

Totally agree with the race pad and dimple/grooved/drilled disks on the back being a waste of time theory as the disks really suffer from scoring. Ran drilled all round before i upgraded to monoblocks and believe all it did was dramatically reduce disk life.
However the option of a larger oe disk/caliper/pad configuration on the rear to go with the monoblocks is not a bad idea at all. Audi set the brakes up with the sizes of the disks being, in most peoples opinion, inadequate even for a fit car in mild tune. So to increase the front rotor size it seems only sensible to do the same to the rear at least in proportion. Paul has done loads of work on this and he isn't the sort of chap to upgrade for a pose, increasing rear brake efficiency in proportion to the front is what i intend to do eventually and pauls upgrade seems very sensible to me, oe plain disks and oe pads are the way to go.

[Wolfgang]

hello vincent,

as you can imagine i´m not pleased seeing you using my car as avatar.

this picture is either from www.tots.ch or from www.audi-vw-projekt.de

i hope you´ll delete this picture in order to use another one. Perhaps one of YOUR car?

have a nice day,

wolfgang

[caterpillar]

org s4 rear vent disk å calipter( 270x20) may fit ( 5x112) its org part from audi

[Wolfgang]

omg, nothing changed in his avatar yet.

@caterpillar

it isn´t that way easy as you are writing. the problem with this brake and these carriers is that there is a 5-7mm spacer under the brake-disc needed.

hopefully my english is understandable enough, not knowing how to describe the problem better.

have a nice weekend,

wolfgang