Well the main thing here is, for those that can, this isn't a difficult thing to try and is easily reversible. On the up side (in a big way) at least you'll be getting rid of those flimsy disc guards.

lol You love those guards too?! lol

I mean why does the R32 have 330 upfront and, is it 288mm at the rear?

I know its four wheel drive but to be fair thats not got a lot to do with it.

Nope, the Mk4 R32 has the same 256x22mm rear discs as the Mk1 RS. Identical rear brake setup with the same discs/pads/calipers.

R32 fronts are 334x32mm, RS fronts are 312x25mm.

Nope, the Mk4 R32 has the same 256x22mm rear discs as the Mk1 RS. Identical rear brake setup with the same discs/pads/calipers.

R32 fronts are 334x32mm, RS fronts are 312x25mm.

Oh right!

Perhaps im thinking of the Mk5 then!?

But i thought there was a rear brake upgrade as such for an RS, from something like an R32?

Right made a mock up bracket!

Works a treat, just need to take it to an engineering company to get two made

Will be back once i get them!

Interesting

Don't forget to talk to them about a possible bulk purchase. Big it up, make it sound like an essential mod, and they may tweak the price in your favour. Of course there is always the possibility that you find it is an essential mod and drum up some interest. And of course you'll have done the groundwork already. People have made similar projects turn out lucrative in the past.

Yeah cant be too interested though as they might put the price up! lol

I'm surprised that the rear calipers with new pads will fit over a 25mm thick disc, and not drag. You're obviously increasing the disc thickness by 3mm, but using the original calipers and pads designed to work on a 22mm thick disc.

You'll also be left with an unsightly wasted unswept area, so you may want to get the 312mm disc faces sprayed with an anti-corrosive coating like Geomet to stop the epic rust! The 312mm discs are designed to be used with pads that are 74.2mm tall, but the rear pads are only 51.3mm tall. So you'll be left with a 23mm unswept band.

If the disc offsets are different, then I suppose you can get around that with the bracket design. But since you still have to use the standard carriers, you're having to add an extra bracket between the carriers and hub mounting face. Obviously that'll weaken the joint, and you'll see more caliper deflection unless your adapter bracket is a beast. Once the rear caliper is spaced out to fit over the 312mm discs, then you have to worry about wheel clearances. I'm guessing the 17" spiders still slide over fine without spacers?

You're increasing the radial distance from the braking surface to hub centre, so you get more torque advantage. But that increased torque has to be reacted by the carrier, your adapters and the carrier mounting face on the rear beam. So I'd worry about the fatigue of those components, seeing as they are being operated beyond their design limits. Maybe beef things up a bit, or run some FEA and BJA simulations if you can get the software.

The performance downside of this is that you have more mass to accelerate and deccelerate. I don't know the weight differences between the discs, but you could find out.

If you're planning on running no disc shields, then try it out on a waterlogged motorway and see if you have any more problems than normal. The shields attempt to stop a film of water building up on the discs, to help avoid that brown pants moment when you initially stamp on brakes in the wet and they take a second to bite!

I would have said what's the point in doing this to an old diesel octavia, which already has brakes that are more than capable for it, but then it's your car so you can do whatever you want! It must be a nightmare detailing all these non-standard changes you've made to you insurance company though....

Right....

1. Calipers and pads fit fine

2. Yeah there will be an unswept area as there are with Porsche Callipers, see front of car!!! But I use Pagid discs which are coated and you put them on and the pad area cleans off the protection so the area not used wont rust or look unsightly

3. Spiders do fit as you are using the same disc as the front with a smaller calliper, so no issues there!

4.Using steel to make the brackets will be more than strong enough as the originals are cast which means they are in fact more brittle and weaker than the stronger steel which will be softer, so....

Steel, case hardened to stop corrosion should be spot on!

5. Mass and weight difference isn’t an issue as the 312 disc isn’t that much heavier.

6. Discs shields aren’t designed to keep out water more to stop damage to the inside of the disc but if they were I’ve got a spare set of fronts that ive worked out how to fit to the rear to cover the disc.

7. And is there any point doing this to a Diesel Octavia?

Probably not! but I’ve got the time, the knowhow, the tools and the parts in the garage already so why not !

I know it’s a Diesel but it’s got all the same bits as an RS but yet it’s cheaper on insurance, tax gives better MPG and its faster!

And to be fair if we were going to go down that route is it really worth bothering modding and Octavia at all?

As it’s not got a very good Chassis, its wrong wheel, sorry front wheel drive, common beam rear axle, and not even trailing arm!

And the only things that make it special above and beyond a taxi are the stick on Halfords bits and a bit of green paint apart from that it’s any other old Octavia!

But perhaps that’s why we love um lol

Edited 13 July, 201114 yr by dannyboy759

I still think your running the risk of overbraking on the rear however you don't seem to want to listen to any advice so carry on.

just for reference, compbrake 330mmx28mm vented rear disc with oem caliper

I have to admit, it looks a bit weird when the caliper doens't cover the disc.

Does it brake any diffently?

I still think your running the risk of overbraking on the rear however you don't seem to want to listen to any advice so carry on.

So you have a lot of experience with over braking then?

You sound like and expert?

This was just a little project as i had the parts to see what it looked like if it could be done and how it felt

It not supposed to be some F1 Race winning braking system!

Just a bit of fun that i thought some of you guys on here might be interested in if it hadnt been done before thats all

And i thought Audi drivers were the stuck up ones!!!!

So you have a lot of experience with over braking then?

You sound like and expert?

This was just a little project as i had the parts to see what it looked like if it could be done and how it felt

It not supposed to be some F1 Race winning braking system!

Just a bit of fun that i thought some of you guys on here might be interested in if it hadnt been done before thats all

And i thought Audi drivers were the stuck up ones!!!!

I look at like this if they spend billions designing a car and that includes fitting smaller brakes on the rear, it has to be a reason, but if a man in a shed knows best then as I said earlier carry on.

I still think your asking for trouble myself.

Only been working on cars for 20 years so maybe I am not an expert but I do know how little work rear brakes do or need to do.

I look at like this if they spend billions designing a car and that includes fitting smaller brakes on the rear, it has to be a reason, but if a man in a shed knows best then as I said earlier carry on.

I still think your asking for trouble myself.

Only been working on cars for 20 years so maybe I am not an expert but I do know how little work rear brakes do or need to do.

Yeah know what you mean, but what youve got to think is nothing is a good as it could be, and with a performace increase and a front braking increase why not up rate the rears too!

I know car companys spend millions on developement but this goes back to what i say about an EGR on a diesel, its there for a good reason, why take it off?!!!

Its only a project to keep me ouit of trouble with some bits ive already got but im keen to see what the results are

I say go for it mate. If it turns out to be pants, you can always re-fit the old discs. Some people on here do some pointless mods anyway. It's nice to see someone thinking out of the box. It may not work, but there's only one way to find that out.

I say go for it mate. If it turns out to be pants, you can always re-fit the old discs. Some people on here do some pointless mods anyway. It's nice to see someone thinking out of the box. It may not work, but there's only one way to find that out.

Ny point exactly

just for reference, compbrake 330mmx28mm vented rear disc with oem caliper

That looks crap. doesnt look right at all.

So you have a lot of experience with over braking then?

You sound like and expert?

This was just a little project as i had the parts to see what it looked like if it could be done and how it felt

It not supposed to be some F1 Race winning braking system!

Just a bit of fun that i thought some of you guys on here might be interested in if it hadnt been done before thats all

And i thought Audi drivers were the stuck up ones!!!!

heard this once:

EX = something that has been

sPERT = a drip under Preasure.

Mine dont look anything like that!

That doesnt even look like the caliper is even on the disc!!

Mine dont look anything like that!

That doesnt even look like the caliper is even on the disc!!

what happend to ur project??whats the result??did u fix them??just curious...

Search through his posts. He started another thread altogether.