Thread: Can you improve RRC BRAKES?

Originally Posted by clubagreenie

Change from rubber to braided hoses. Especially if they are old and swollen. They swell on the inside so you can't push as much fluid as easy plus generally soften so they expand under pressure.

I agree, I changed to braided hoses front and back. The brake pedal feels better than my l322 using 110 defender calipers, new rotors, discovery brake booster and master cylinder.

Especially given the number of hoses involved.

I fitted EBC Greenstuff pads (Kevlar pads) and Britpart drilled and groved discs to my 130 and the difference is amazing. They aren't so good when cold, but when they warm up they will certainly stop you in a hurry! This might be an easier option if you didn't want to go for a complete brake system change.

I'm now confused,

I have a 1986 RRC, which Defender Calipers and discs do I use? Or are they bits and peices. AND can I use orginal Brake booster and Master cylinder?

Cheers NAT

Originally Posted by nat p

I'm now confused,

I have a 1986 RRC, which Defender Calipers and discs do I use? Or are they bits and peices. AND can I use orginal Brake booster and Master cylinder?

Cheers NAT

Part numbers are all listed on page 2 of this thread.
Disc rotors are all the same. Just make sure you match vented or not vented rotors to vented or not vented calipers.

The original booster and MC work perfectly. But you need to replumb your vehicle to single line front brakes. This can be done using all the original lines and fittings, I only had to make one plug and that was for one port in the pressure reducing valve.
The MC has two stages, one has more stroke than the other. The stage with more stroke needs to go on the front calipers as it's pushing twice as many pistons as the other stage plumbed to the rear.

You will have to clearance some corners on the caliper mounting tabs with a grinder

Just some thought s I had about this thread.
You are not really improving the Brakes of a RRC by doing this mod but improving the "feel" of the brakes.

The limitinng factor of brakes is the area of pad onto the disc, and certainly you can generate enough friction with standard pads to boil the fluid and burn the paint off the backing plates.

Fitting performance brakes on most cars entail increasing the pad area eg falcon GT with Brembo or Commodore performance brakes where 6 spot calipers are fitted so that the pad area is increased. In this case I believe they also increase the Master cylinder diameter to restore the master to caliper displacement ratio.

What I think is happening is that with this mod you are changing the mechanical/hydraulic displacement ratio from Master cylinder to calipers which gives you a higher ratio but increases pedal travel by a proportionate amount.

Given that RRC brakes can "knock back" quite easily , I wonder if it is possible to run out of pedal travel on first application, just when you do not need it as certainly I have had the experience on long trips where the bearing have slackened a bit that the first application can see a lot of pedal used.
While I agree that RRC brakes can have a hard pedal, I think a real upgrade would involve increasing pad area and subsequently master cylinder volume..

BTW, vented discs only reduce the speed of heat build up of the calipers/pads/disc and are manily designed to reduce fluid boil on long applications. They have no role in feel.

I have never been able to find an upgrade involving larger pad area.
I tow an unbraked trailer of about 650Kg and I must admit that I would like to see more effective brakes, but when I look at my pads , I find that they have got really hot, and I have actually pushed through the anti squeal backing. This is on EBC black which I would not get again.

So to me the answer is more to do with a good soft pad material which has high friction but retains it when very hot. I have yet to find it.
Regards Philip A

No, it increases the braking dramatically, applying more force to the pads, it works....well

Originally Posted by PhilipA

Just some thought s I had about this thread.
You are not really improving the Brakes of a RRC by doing this mod but improving the "feel" of the brakes.

The limitinng factor of brakes is the area of pad onto the disc, and certainly you can generate enough friction with standard pads to boil the fluid and burn the paint off the backing plates.

Fitting performance brakes on most cars entail increasing the pad area eg falcon GT with Brembo or Commodore performance brakes where 6 spot calipers are fitted so that the pad area is increased. In this case I believe they also increase the Master cylinder diameter to restore the master to caliper displacement ratio.

What I think is happening is that with this mod you are changing the mechanical/hydraulic displacement ratio from Master cylinder to calipers which gives you a higher ratio but increases pedal travel by a proportionate amount.

Given that RRC brakes can "knock back" quite easily , I wonder if it is possible to run out of pedal travel on first application, just when you do not need it as certainly I have had the experience on long trips where the bearing have slackened a bit that the first application can see a lot of pedal used.
While I agree that RRC brakes can have a hard pedal, I think a real upgrade would involve increasing pad area and subsequently master cylinder volume..

BTW, vented discs only reduce the speed of heat build up of the calipers/pads/disc and are manily designed to reduce fluid boil on long applications. They have no role in feel.

I have never been able to find an upgrade involving larger pad area.
I tow an unbraked trailer of about 650Kg and I must admit that I would like to see more effective brakes, but when I look at my pads , I find that they have got really hot, and I have actually pushed through the anti squeal backing. This is on EBC black which I would not get again.

So to me the answer is more to do with a good soft pad material which has high friction but retains it when very hot. I have yet to find it.
Regards Philip A

No.

More clamping force is the #1 way to improve brakes. Pad area is minor, almost insignificant.

Attempting to increase MC volume through stroke will have no effect. Attempting to increase MC volume by larger MC piston will reduce braking force. It is the exact opposite to fitting larger calipers.

Boiling brakes is about heat rejection, not stopping force. Heat rejection is improved by better airflow through and over the brakes (vented rotors, more open wheels etc). Or just by not driving like a plonker.