Hi every one I have a mild modified fabia vrs and one of the mods are some 312mm front brake set up.

I now wish to upgrade the rears to some oct vrs! I hope this may balance out my braking because all it wants to do in the wet is lock up! and Its getting f##king scary

rear brakes do sod all so octy brakes will just be for cosmetic reasons, not performance. Front brakes do 90% of the work.

It won't lock up though because the ABS will kick in.

You'll notice that the rears are probably fairly rusted up so some good hard stops in the dry might well clean them up and address any issues you're seeing.

I have had situations where the back of the car felt like it was going to swing around under emergency/extreme braking. The brake balance of the car is easily adjusted by fitting the relevant hydraulic distribution box and a set of Octavia vRS rears make the car stop even harder.

OEM+ is fine, but sometimes you do need to go to a Motorsports Tuner and have things modified. I think the total cost of brakes is about £1000 for the complete fronts, rears and the small modifications to be able to adjust the balance. You can also adjust the braking force required by changing the Master (I think) Cylinder, so you can put your passengers though the windscreen with a dab of the left foot.

It depends what you're after, really. The standard 312mm upgrade is brilliant though.

I hope this may balance out my braking because all it wants to do in the wet is lock up! and Its getting f##king scary

drive slower for the conditions and brake earlier

and as someone has already said , if the ABS is working , this will kick in before the wheels lock up completely

good tyres would also help

Scary brakes! as others say they should not lock up else you have a faulty ABS system. Also you should not brake on corners only in a straight line, SOP's.

Yer I realize the abs will kick in. And I Have built several rally cars with bias box e.t.c

but all I realy want to know is will the ocy rear disc set up bolt on? or will i have to cut, weld e.t.c

as for the cossmetics, the disc's are larger on the rear of a ocy vrs and should help the bias.

It's a straight bolt-on. but you will need to adjust the bias to get the full benefit as, has been pointed out, the standard set-up is very heavily front biased.

It's a straight bolt-on. but you will need to adjust the bias to get the full benefit as, has been pointed out, the standard set-up is very heavily front biased.

when you say standard set up do you mean the disc's and calippers off the ocy vrs?

or the stand fabia vrs pedel box?

Thanks Richie

when you say standard set up do you mean the disc's and calippers off the ocy vrs?

or the stand fabia vrs pedel box?

Thanks Richie

The hoses, carriers, discs and pads from an Octavia vRS will bolt straight on. I don't recall mentioning the pedal box, but if you want to adjust the brake bias, you will need to install that device as well.

You dont need to adjust the brake bias, for the same reason the car doesnt have a load valve on the rear axle. The ABS system should do it all for you. What are your tyres like? Pressures? These have far more effect of braking than a bias system. How are your console bushes and dampers?

Im running 312mm front and 256 rears, not noticed any difference in day to day driving since fitting the bigger rears.

You dont need to adjust the brake bias, for the same reason the car doesnt have a load valve on the rear axle. The ABS system should do it all for you.[/Quote]

I genuinely, really, honestly, hate to disagree, but if you want the back brakes to work more of the time, you do need to adjust the brake bias. I don't want the backs to start working when the fronts lock up, I want them working all the time, as I did notice that under extreme braking the back of the car would go very light indeed. With the bias adjusted more to the back of the car it brakes flatter and feels more planted.

Im running 312mm front and 256 rears, not noticed any difference in day to day driving since fitting the bigger rears.

Surely, that's to be expected as the back brakes on an unmodified Fabia only come on to balance out the fronts and when the fronts start to think about locking.

Hi all I have the same problem with the front brakes and the back willing to swing. I have the feeling that it will jump in the air under heavy braking. My car specification is 288 3G dimpled and ferodo ds2500 in the front, ATE calipers, and zimmerman with EBC green in the back.Goodridge hoses,tyres: KLEBER Hydraxer 205/45/16, 30 psi front and back, weitec hicon GT coilies with little mileage.

The ABS is properly kicking in but still I get the feeling that the back is being forced up under heavy braking.

Anything i can do to eliminate this?

I can't say I recognise the problems here, but it seems to me that if the sensation of a loose rear end isn't down to the choice / condition of the tyres, then it could be related to harsh braking without first hinting to equalise pressure on all four sets of pads - see below for more details:

Don Palmer's Driving Handbook

Otherwise, the only other thing I can suggest is maybe that there are uprated pads on the front, but not on the back. In my case, both the front back discs have remained clean as long as I've had them, and I've never had any issues with brake balance, even when trail braking, or on wet / poor surfaces... :confused:

Hi all I have the same problem with the front brakes and the back willing to swing. I have the feeling that it will jump in the air under heavy braking. My car specification is 288 3G dimpled and ferodo ds2500 in the front, ATE calipers, and zimmerman with EBC green in the back.Goodridge hoses,tyres: KLEBER Hydraxer 205/45/16, 30 psi front and back, weitec hicon GT coilies with little mileage.

The ABS is properly kicking in but still I get the feeling that the back is being forced up under heavy braking.

Anything i can do to eliminate this?

I have the same problem, but, only in track days. On public road it is infrequent phenomenon...

Check your wheels condition, and try next time to put on Michelin pilot exalto 205/45/16 (The best tyre for Fabia and Greek roads' condition). Also check the alignment of the front wheels.

I genuinely, really, honestly, hate to disagree, but if you want the back brakes to work more of the time, you do need to adjust the brake bias. I don't want the backs to start working when the fronts lock up, I want them working all the time, as I did notice that under extreme braking the back of the car would go very light indeed. With the bias adjusted more to the back of the car it brakes flatter and feels more planted.

Surely, that's to be expected as the back brakes on an unmodified Fabia only come on to balance out the fronts and when the fronts start to think about locking.

ok so how do you adjust the bias with out a bias comp pedal box?

as for bushes e.t.c the car is fully poly bushed plus cupra arm bushes, oem pads all round, yoko pradars 215/40/17 on tt comps, kw coilovers, awsome gti rear arb strut brace and just had the tracking done.

the car is so bad in the wet I am thinking of going back to std fronts!

but if a bigger rear set up works I would rather that.

thanks for the help so far every one

I looked into this back in 2005. I ended up putting 15mm rear spacers on, combined with a jabba rear arb stabilised the rear of the car under very heavy braking.

Either that or get used to it and use it to your advantage. Skittish rear end is quite fun if you know its coming.

Skittish rear end is quite fun if you know its coming.

:rofl:

ok so how do you adjust the bias with out a bias comp pedal box?[/Quote]

On the invoice it says 'fitted brake bias valve'. Does that help? I don't do spannering, I have someone who does that:D

the car is so bad in the wet I am thinking of going back to std fronts![/Quote]

That really doesn't sound like what I had. If I pulled a real EMERGENCY braking manouevre, the back end would go very light and it would feel like it was liable to swap ends if any steering was applied. Under normal - even 'pressing on' type road use, it felt fine. Now, with more rear bias on the brakes, it brakes absolutley flat and feels secure.

but if a bigger rear set up works I would rather that.[/Quote]

I think a bigger rear setup will only help if they come on, which they don't unless you change the brake bias.

On the invoice it says 'fitted brake bias valve'. Does that help? I don't do spannering, I have someone who does that:D

That really doesn't sound like what I had. If I pulled a real EMERGENCY braking manouevre, the back end would go very light and it would feel like it was liable to swap ends if any steering was applied. Under normal - even 'pressing on' type road use, it felt fine. Now, with more rear bias on the brakes, it brakes absolutley flat and feels secure.

I think a bigger rear setup will only help if they come on, which they don't unless you change the brake bias.

My car is planted! it want go light on the rear but it brings the abs on way to easy.

By fitting larger diameter disc's on the rear you will increase the braking effect on the rear.

It the same theory as putting bigger on the front.

a for the bias valve you must have an in-line adjustable valve.

Or the standard valve that comes out of your master cylinder on the rear lines have been changed to allow more flow.

Since the 312mm vented front / 255mm solid rear is the same as the old 2WD TT, maybe a bias valve from one of them was fitted?

My car is planted! it want go light on the rear but it brings the abs on way to easy.

Never had a problem with the std rears and TT fronts, either on the road or track, if you have decent rubber and don't brake using a lead foot at every corner then I can only think it is an issue with your ABS.

I have the same problem, but, only in track days. On public road it is infrequent phenomenon...

Check your wheels condition, and try next time to put on Michelin pilot exalto 205/45/16 (The best tyre for Fabia and Greek roads' condition). Also check the alignment of the front wheels.

Wheels are new, but maybe I have an issue with alignment, I'll have it checked. Thanks kdouris.