People with big brake kits

[Dave_Bayern]

Can you tell me, or even better post a pic of the pad contact area.

Say for example you have a big brake kit, does the pad cover the entire disc, or just some of it?

Just a picure of the calipers on the disc would be fine, just to see how much of the disc the pads come into contact with....

 

[ChriS3]

Any use?

 

[Dave_Bayern]

Am wondering if the following would be a suitable amount of pad contact area in comparison to other kits.

The discs shown are 312mm.

 

[Dave_Bayern]

Thats fantasic Chris, I assume the pads come very close to the hub?

So most of the disc is swept by pad?

 

[ChriS3]

Thats fantasic Chris, I assume the pads come very close to the hub?

So most of the disc is swept by pad?

Looks that way. You'll end up with some strange wear patterns, but I think it'll work, technically speaking. Just not at it's prime. Here's my big rear discs for comparison - 308mm, standard caliper.

 

[jojo]

On my Brembo GT's Dave, the pad sweeps the whole of the disk area(don't have a close up pic - sorry), and looking at the second pic you posted, you would get a groove all the way round the disk once it starts to wear down.

 

[Prawn]

yea jojo, we realise that on most proper big brake kits the pad sweep is the same as the rotor.

the question is, we know it will look a bit random, but is there any reason the setup dave posted above wont work?

im in the same position as dave. ive got the same calipers and 312mm S3 discs, and i dont see why it wont work.

sure, there will be some disc untouched by the pads, but is this reall an issue?

one option would be to machine the discs down to around 300mm, and machine the carrier accordingly so it looks a bit more normal. but is there any point sacarficing power all for it to look 'right'?

so.

anyone with any sensible reason why the above setup shouldnt work, speak up!

 

[CLS3]

Prawn and Dave,

if these are Boxster rear calipers, I ran these with S3 discs on my A3 1.8T Quat for a while, they worked fine, a massive improvement on the standard A3 braking ability, due to the larger diameter discs over the A3 ones not sure how much improvement there would be on an S3, but the offset was wrong on my caliper carriers and the calipers scored the back of the discs otherwise I would have kept them. So i bit the bullet and bought the Brembo kit. But with the correct carriers they would be fine...not ideal but fine.

Pics below of both set ups. Hope this helps... Chris

 

[Prawn]

CLS3, i think you could well by me new best friend....

ive had a few rather irritated phone calls from dave tonigh, saying hes giving up, and now saying hes selling his calipers! but im CERTAIN it can be done!

what carriers were you using on that setup? daves lined it up with ibiza cupra R carriers and says its MILES off and the carrier will need 7mm taking off the hub mounting face, which is severe!

the calipers in your picture are indeed the ones we have! and apart from that silly rust line (which can be cured with some paint) they look awesome!

if they scored the back of the discs slightly, but enough to work, surely with a little clever machining they could be made to work fine?

if you could let us know what carriers you were using, ill get myself a set, and we are back on track!

thanks!
Nick


(ive PMd you incase you dont check this thread again)

 

[Dave_Bayern]

CLS3 - Thats great, that is indeed what they are. The are actually 996 rears but same part number as Boxster rear. Mine are anodised, i think Boxsters are painted.

Anyway, yeah, I wasnt sure if there would be enough pad contact, but you are saying its OK?

I was intending to run this on a 255Bhp A3, so plenty power, but then considerably lighter than a A3 Quattro.

I was considering running it with 288mm discs but considering the pad area is 15mm smaller than standard pads, it seemed to make more sense to have that smaller contact area on bigger discs, due to stopping being better on the outer edge of bigger discs.

Is there a massive difference between the braking power of the Boxster rear and Brembo setups? The Boxster rears are monobloc and therefore lighter, and the piston sizes are a MUCH closer match to the Audi master cylinder so in pure physics, the calipers should be preferable.
Was the scoring the only reason you changed, is there marked difference in braking?

Bear in mind I wanted this to be a cheap braking solution for track days....

 

[CLS3]

Right then...!! Nick and Dave where do I start!

I bought the calipers with carriers which were custom made apparently, I went to AMD when it was still AMD and they said they were Seat Leon (? don't quote me on that it was a long time ago) carriers iirc but with a bit machined off. Thats the bit i needed!

Basically the surface of the carrier which bolted to the upright had been machined flat and there should have been two lugs on there of about
3mm each.

When I fitted them initially I spaced them off of the upright to get the right offset for the S3 discs with 6 washers 3 at each bolting point, and yes they were normal S3 discs 312mm. I had the idea that I would run them like this, not an ideal solution, until I had the time to turn myself some proper spacers up to fit between the carrier and the upright, I never got to this point!... After not long at all the washers compressed as I thought they would and the 2 lugs on the inside of the caliper in the recess where the pads sit started to score the discs, not badly to start with but constantly. I checked them and decided that I couldn't run them like this and took them off and replaced the whole set up with the Brembo set up as I got a deal on them through work.

No radial spacing was needed at all with my carriers. Just offset.

The braking performance on an A3 was vastly improved and if you can get the offset problem sorted I would recommend them as an upgrade. The pad contact was fine as it was further out on the disc, the distance from the centre of the discs was more so the force applied to had more stopping power.

I'm not sure about ibiza carriers, never seen a pair tbh but 7mm does sound severe but if thats the difference between the offsets then so be it! Tbh if radial spacing is needed to get the carriers to fit scrap them, get a set that needs some adjustment to offset and it is a lot easier, or no adjustment at all would be even better!

As Nick says a bit of high temp paint will sort the lovely corrosion line nicely!

As dave says the pistons on the 996/Boxster calipers are closer to the A3 master cylinder, the pistons on the 996/Boxster calipers are smaller than the Brembo ones.

and yes the scoring was the only reason I changed, I felt like I had been fighting an uphill battle, I had had custom Goodridge hoses made, tried and tested about 3 different front discs and looked into different carriers and when the discs started scoring I was at the point where I felt better just scrapping the set up and buying the Brembos through work. They are on the S3 now and are the best money I've ever spent on it so far!

Hope I've covered all of your questions, If you need to know anything else just ask.

Hope that helps a bit Chris :icon_thumright:

 

[Prawn]

Right then...!! Nick and Dave where do I start!

I bought the calipers with carriers which were custom made apparently, I went to AMD when it was still AMD and they said they were Seat Leon (? don't quote me on that it was a long time ago) carriers iirc but with a bit machined off. Thats the bit i needed!

Basically the surface of the carrier which bolted to the upright had been machined flat and there should have been two lugs on there of about
3mm each.

When I fitted them initially I spaced them off of the upright to get the right offset for the S3 discs with 6 washers 3 at each bolting point, and yes they were normal S3 discs 312mm. I had the idea that I would run them like this, not an ideal solution, until I had the time to turn myself some proper spacers up to fit between the carrier and the upright, I never got to this point!... After not long at all the washers compressed as I thought they would and the 2 lugs on the inside of the caliper in the recess where the pads sit started to score the discs, not badly to start with but constantly. I checked them and decided that I couldn't run them like this and took them off and replaced the whole set up with the Brembo set up as I got a deal on them through work.

No radial spacing was needed at all with my carriers. Just offset.



I'm not sure about ibiza carriers, never seen a pair tbh but 7mm does sound severe but if thats the difference between the offsets then so be it! Tbh if radial spacing is needed to get the carriers to fit scrap them, get a set that needs some adjustment to offset and it is a lot easier, or no adjustment at all would be even better!

hmmmmmmmmmm

thanks chris, at least we now know it can be done!

what did you do with your setup? you dont still have the carriers around do you?

interesting that they could be leon carriers, i assume the maching down was to take the disc size down from 323 down to 312? and the offset was done entirely with spacers?

if the only problem you had was the washers compressing, then in thoery at least, if we get some proper spacers made up for the offset, we will be sorted!

if youve got any pics of the carriers that would be awesome, or if on the off chance you still have them lying around, ill happily buy them from you!

thanks for all your help. at least we know its possible now. i just dont want to waste a fortune on the wrong carriers

i wonder how much a set of LCR carriers cost!

 

[CLS3]

Just found these actually...they might help a bit...














I've got some pics of the Goodridge Hoses too if you need them.

 

[CLS3]

Sorry Nick, I sold the entire setup to a guy on RS246, for his S2. But hopefully those pics might help a bit.

I know big boys toys own AMD now but AMD used to have the correct carriers for them. If they still do them then they would work for sure. I think LCR carriers would work too, but prob worth getting you hands on a set and offering them up and seeing. Think they can be £££.

 

[Dave_Bayern]

Oh thats great, it has given me an idea, as the carriers are similar to the Ibiza Cupra R ones, well, they would be if I had the Ibiza ones machined.

The brakes hoses are fine, they are standard Audi fitment with Banjo-Porsche converters on them, which I also have.

I 'might' look into actually using these for a short while, but I think I will end up replacing the calipers with something that uses a bigger pad.

 

[Prawn]

awesome, thanks Chris, thats a big help. those carriers look VERY like the ibiza cupra R carriers too.....

sorry to keep asking questions, but which face on those carriers was machined? was it the two flat faces where the caliper meets the carrier, or the face what bolts up against the hubs on the car to alter the offset?

i might give AMD a call this week, although now theyre BBT owned i wont hold out too much hope.

 

[CLS3]

Hi Nick,

The carriers were machined on the two faces which bolt up against the upright on the car. this is where i had to put the spacers (washers!!)

def worth giving AMD a call, the set I saw had their name machined into then, very smart they looked to but not sure if they have stopped the production now.
Prob best to phone up explain what you have and see what they say.

If you did need any spacers turned up for the Ibiza carriers if you need to space them off of the upright to get the offset right, I would be more than willing to do it, I can do them at work, If that helps.

Chris

 

[Dave_Bayern]

I have the Ibiza Cupra R carriers, and it needs 3.6mm of radial spacing to accomodate the 312mm discs, this is fine though, as i have a length of 3.6mm steel.

If your were the Leon carriers (I reckon they were too) then you'd need both faces machining off, as the Leon carriers are designed for 323mm discs.

I found the offset on the Ibiza carriers when mated to 312mm discs means that the caliper sits approx 6-7mm too far forward, and thus material needs to be removed to allow the caliper to sit central to the disc. Which is odd, considering you needed to add that amount with the Leon carriers. I wonder if they were designed for a different purpose? (Like S2 or Mk2 Golf)

You know you said your pins started digging into the discs?

Were your pins modified in any way? The standard thickness of Boxster/996 rear discs is 22mm and the pins are spaced 24mm apart.

I have taken off an extra 3mm or so on each pin to allow the 25mm disc to locate and room for heat expansion. They are toughened though and I blunted 7 hacksaw blades doing one caliper.

 

[Prawn]

ah, this is making more sense now.

the LCR carriers are designed for the Audi disc offset, which explains why you needed to space yours, not maching it down. the ibiza carriers we have, are designed for a disc which sits further out. hence it needing to be machined down to fit right.

the LCR carrier idea sounds right to me in terms of offset, but i dont quite see how it worked with a 312mm disc when the LCR is a 323mm disc!

ah well. ill give AMD a call this week and see what they say!

thanks for all your help, its great to know it WILL work.

dave, did you not try using an angle grinder on those pins>? i know thats how ill be taking mine back!

 

[CLS3]

I have the Ibiza Cupra R carriers, and it needs 3.6mm of radial spacing to accomodate the 312mm discs, this is fine though, as i have a length of 3.6mm steel.

If your were the Leon carriers (I reckon they were too) then you'd need both faces machining off, as the Leon carriers are designed for 323mm discs.

I found the offset on the Ibiza carriers when mated to 312mm discs means that the caliper sits approx 6-7mm too far forward, and thus material needs to be removed to allow the caliper to sit central to the disc. Which is odd, considering you needed to add that amount with the Leon carriers. I wonder if they were designed for a different purpose? (Like S2 or Mk2 Golf)

You know you said your pins started digging into the discs?

Were your pins modified in any way? The standard thickness of Boxster/996 rear discs is 22mm and the pins are spaced 24mm apart.

I have taken off an extra 3mm or so on each pin to allow the 25mm disc to locate and room for heat expansion. They are toughened though and I blunted 7 hacksaw blades doing one caliper.

What diameter are Ibiza CR discs standard? smaller than 312mm i'm guessing? hence the radial spacing.

Whats faces would need maching off of LCR carriers to get them to fit 312mm discs instead of 323mm? that is different discs diameters not different offsets.

The offset on my LCR carriers may well have been perfect if the guy ho had them before me hadn't had them machined down. but as he did I had to space them to get the offset right to the discs to get the discs to sit in the middle of the caliper.

I don't think my pins in the calipers where modified at all, I didn't anyway. They fitted over the discs fine and with room to spare until the washers compressed.

ah, this is making more sense now.

the LCR carriers are designed for the Audi disc offset, which explains why you needed to space yours, not maching it down. the ibiza carriers we have, are designed for a disc which sits further out. hence it needing to be machined down to fit right.

the LCR carrier idea sounds right to me in terms of offset, but i dont quite see how it worked with a 312mm disc when the LCR is a 323mm disc!

ah well. ill give AMD a call this week and see what they say!

thanks for all your help, its great to know it WILL work.

dave, did you not try using an angle grinder on those pins>? i know thats how ill be taking mine back!

Think you have it spot on there Nick!

It worked fine with a 312mm disc about 1mm of pad did hang over the back of the discs but getting LCR discs 232mm is impossible or very £££ well it was when I was trying. No one could get them. Eurocar parts, AMD GSF no one. I think they would be the ideal solution with LCR carriers. but see what you can get.

Chris:icon_thumright:

 

[s3ollie]

You could get custom brackets and run the TT 3.2/R32 334x32 discs. a bit cheeper and easier to come across. if your calipers go that wide.

 

[mk1chopper]

ibiza cupra r run 305mm iirc

Has anyone ever looked at using brembos of an alfa gtv or fiat coupe turbo? I know someone on performance vw forum spoke of using 300zx calipers on a mk2 golf, iirc 300zx front disc are 280mm, so you could you use them on standard a3 disc if you had a custom bracket made up?

 

[Dave_Bayern]

Fiat Coupe are 304mm, so probably very similar to the Ibiza Cupra R calipers.

Pads are the same as Focus RS.