Early 156 Rear Brakes

Would it be easy to upgrade from the early 156s small rear brakes to the larger rear brakes that the later 156s got? When I get around to doing the fronts I think it might be necessary for me to do the rears as well to keep the balance right.

This would be changing from the 251mm brakes to the 276mm brakes. Alternatively, could the old front brakes (284mm) be mounted on the rear when I upgrade to the bigger new front brakes?

No point doing either.
The rear brakes do very little anyway.

Originally Posted by David C

No point doing either. The rear brakes do very little anyway.

What he said.

Originally Posted by David C

No point doing either.
The rear brakes do very little anyway.

I'm not disagreeing with you, but if so why did Alfa upgrade them on the later cars? With the weight distribution of the car, and the weight shifting forward under high deceleration, I know the rear brakes are doing something like ~10% of the total work done.

But I should be fitting an 8-pot front brake kit with 330mm discs in a month or two, you don't think the extra work done by the front brakes would mean the rear brakes are doing more than they could cope with? Maybe it would just be best to deal with this if it arises, rather than in advance..

Heard it said many times that the rears dont do much but why then did Alfa bother to change them to 276mm or was this because their parts bin ran out of the smaller brakes?

When I fitted DS2500's to the rear of my car I noticed a worthwhile improvement in braking - definitely felt like the front was having to do less - this was with the Brembo setup on the front.

As an example of the lack of need for big rear discs.

Attached is a pic of the front & rear discs from Giovanardi's 1998 156 Supertourer.

(the front disc is the one on the right... )

Originally Posted by Pascs

Heard it said many times that the rears dont do much but why then did Alfa bother to change them to 276mm or was this because their parts bin ran out of the smaller brakes?

When I fitted DS2500's to the rear of my car I noticed a worthwhile improvement in braking - definitely felt like the front was having to do less.

I put EBC Greenstuff on the rear of my 156 only a few months ago, can't say I noticed any difference, but I think the previous pads were fast road of some sort anyway, either Tarox or Red Dot.

Originally Posted by David C

As an example of the lack of need for big rear discs.

Attached is a pic of the front & rear discs from Giovanardi's 1998 156 Supertourer.

(the front disc is the one on the right... )

Do you know the measurements for those two discs? The rears are tiny!

Originally Posted by Pud237

I put EBC Greenstuff on the rear of my 156 only a few months ago, can't say I noticed any difference, but I think the previous pads were fast road of some sort anyway, either Tarox or Red Dot.

That's because Greenstuff pads are notoriously poor.

Originally Posted by Pud237

Do you know the measurements for those two discs? The rears are tiny!

The rears are tiny and very thin. They used small motorbike discs.

Fronts are 380mm

Can't remember the rears, but I can ask if you need to know.

Originally Posted by Roswell

That's because Greenstuff pads are notoriously poor.

Thats OK then, because:

Originally Posted by David C

No point doing either.
The rear brakes do very little anyway.

Originally Posted by Roswell

What he said. :smug:

If the pads I had on when I got the car are Red Dot, then the Greenstuff shouldn't be much different, Red Dot pads don't have a good rep as it stands. I would have got Ferodo DS2500s or Perfs but they were over twice the price.

A set of DS-Performance pads on the back will last many many rears.
They will also be kind to the disc.


What you don't want on the back is something that doesn't work at all or something that suddenly grabs.
You want a consistent pad with consistent friction cold/hot and is a slightly lower friction than your front pads but with a similar shape friction curve.

That way you don't have the rears working before the fronts in a braking from cold situation.

I think the greenstuff pads are the most 'road friendly' of all the EBC, so will be closest to the standard pads in terms of their specification.

Front pads will definitely be DS2500s after my positive experience with them on the JTD, but I have about half the pad thickness left.

The braking starts from rear. They help only about 5 -10 % depend the application. But rear brakes are important to keep the balance of the car.

The braking starts from rear and Abs unit is removing the fluid pressure just before they block the rear disks. That means if you use bigger (disks or calipers) for the rear you help more the front system.
On slow speeds sometimes the pressure of the rear is enough to stop the car.
About Gta rear brakes or late 156, the calipers are the same and the pad area also. The difference are on the disk and caliper mound lungs.

The difference is bigger on small speed braking than high. If you upgrade to Gta rear brakes even if you don't feel it so much you remove some of the work of the front braking system overall.

About balance you don't need to worry. The EBD unit will make the balance for you.

I have 365mm 8 piston calipers on the front and 305mm disks with 4 piston calipers for rear. They work fine. About the stopping power you
I can describe by words. You have to be in the car to feel...

Don't want to appear a smart arse but the typical brake distribution is around 60% to the front and 40% to the rear. However this is governed by the ABS unit which regulates the brake pressure to each wheel depending on the rotational speed of each wheel, i.e if both your front wheels are about to lock up then most of the brake effort will go to the rear and vice versa. Likewise if you have three overweight passengers in the rear, a boot full of luggage and only your 8 stone self in the front then most of the brake force will be applied to the rear So rear brakes do more than you may realise and are worth looking after

Originally Posted by Pud237

Would it be easy to upgrade from the early 156s small rear brakes to the larger rear brakes that the later 156s got? When I get around to doing the fronts I think it might be necessary for me to do the rears as well to keep the balance right.

Yep, it is one on one fit. Just one thing, you have to be creative with the brake cover plate. Easy mod.

It feels more balanced if you´ve 305 on the front.

Originally Posted by GTAFAN

About balance you don't need to worry. The EBD unit will make the balance for you.

On a standard 1998 156 V6? Didn't think it had EBD, only ABS..

Originally Posted by slysi16v

Don't want to appear a smart arse but the typical brake distribution is around 60% to the front and 40% to the rear. However this is governed by the ABS unit which regulates the brake pressure to each wheel depending on the rotational speed of each wheel, i.e if both your front wheels are about to lock up then most of the brake effort will go to the rear and vice versa. Likewise if you have three overweight passengers in the rear, a boot full of luggage and only your 8 stone self in the front then most of the brake force will be applied to the rear So rear brakes do more than you may realise and are worth looking after

I think it is 60:40 when stationary but the more you decelerate the more the centre of balance shifts forward, the harder the front brakes need to work and the less the rear brakes need to work. Obviously if it is loaded rear-heavy this is less of an issue.

Originally Posted by ClaSSiC

Yep, it is one on one fit. Just one thing, you have to be creative with the brake cover plate. Easy mod.

It feels more balanced if you´ve 305 on the front.

Brake cover plates have rusted through anyway and need removing. I only asked about rear brakes as I am planning an 8-pot 330m front brake conversion

Originally Posted by Pud237

On a standard 1998 156 V6? Didn't think it had EBD, only ABS..

All 156 had EBD.

Originally Posted by David C

All 156 had EBD.

Didn't realise that. Thought it would be part of the traction control system the later ones got.