Technical 257 mm brake discs on panda 1.2 69HP 4x4
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Technical 257 mm brake discs on panda 1.2 69HP 4x4
The Panda Nut
Nutty about Pandas Infected by Panda virus and OPD
Well you can do almost anything if you spend enough, but You need to ask why. What are you aiming to achieve. Messing with the brakes is not something to be tackled lighly. Have you upped the power and need more stopping power? You need to consider wheels and tyres as part of the equation. I know this doesnt answer you question but I think you will be throwing money away. You will need calipers, caliper mounting brackets and probably wheels and backplates etc. The diesel is heavier on the front than the petrol and has a greater capacity to grip hence the bigger discs. If the brakes dont fade and the ABS works Im not convinced you are going to get anything out of it. There are probably mods that will give more back for your money.
If you mess with the brakes you may upset the 4x4 operation as this works using ABS sensors and these too may need to change too. There will be insurance implications too.Sorry for a negative response and I wish you well with upgrading.
If you mess with the brakes you may upset the 4x4 operation as this works using ABS sensors and these too may need to change too. There will be insurance implications too.Sorry for a negative response and I wish you well with upgrading.
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You would need bigger callipers but braking is limited by tyres, weight on the tyres and suspension. Bigger brakes will not improve the stopping power AND as already said you'll probably mess up the braking balance. You will also add another chunk of unsprung weight that further damages grip on rough surfaces.
Alloy hub carriers, alloy callipers and stainless discs would save a lot of weight but such things don't exist unless you have silly money to spend.
Alloy hub carriers, alloy callipers and stainless discs would save a lot of weight but such things don't exist unless you have silly money to spend.
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Standard Panda brakes will lock the wheels so there's no point going for bigger brakes.
vexorg
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The may lock but they will also run cooler and have less brake fade. You also have more control with a lighter touch than trying to gauge how heavy to stomp on the pedal. Jumping from the citroen to the fiat does give an initial thought of what's wrong with these brakes 
The size difference is marginal, so unlikely to mess up the balance since the majority is on the front anyway. And many other manufacturers have bigger breakes on the front for same size rears on the sportier versions.
You might not need different calipers, vauxhall often use the same caliper on bigger brake discs, just the carrier is offset to accomodate the disc.
Wheel clearance would be the main concern, and if you are using standard fiat parts off other cars then there should be no risk of messing with the safety side.
The size difference is marginal, so unlikely to mess up the balance since the majority is on the front anyway. And many other manufacturers have bigger breakes on the front for same size rears on the sportier versions.
You might not need different calipers, vauxhall often use the same caliper on bigger brake discs, just the carrier is offset to accomodate the disc.
Wheel clearance would be the main concern, and if you are using standard fiat parts off other cars then there should be no risk of messing with the safety side.
That. The standard brakes are more than adequate for the performance.
Neither of which is remotely relevant to normal driving in a 1.2 (unless you're planning to take it round a track)
Stomping on the pedal has no place in normal driving unless you are in an emergency situation
Citroens generally have much more powerful servo assistance than most other cars, so pedal pressures are much reduced. Citroen salesmen often find customers on test drives brake much harder than intended until they familiarise with the cars. Personally I like Citroen brakes, but they're not to everyone's taste.
I'd agree that Fiat brakes often lack feel, vibrate, rattle, and snatch, but that's usually down to corrosion causing the pads to bind in the reaction frames. If they're in proper order, then you'll have no problem with braking under full control and there's nothing wrong with the feel or the pedal pressures either. If you are experiencing any of these issues, then the brakes need stripping, cleaning and lubricating.
Ensuring the existing brake setup is in first class condition (discs & pads are cheap enough to change if there's any doubt) will gain you far more than transplanting a set intended for a different model. Doing this will likely involve replacing a lot of parts for no meaningful benefit. And that's before we start discussing the insurance implications.
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TL100HP
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Thank you all for your answers. The main reason for putting on larger and slightly thicker discs (22mm vs 20mm) is mainly to eliminate the fade, which I experience occasionally on downhill “runs”, I live in the mountains.
I have also a Panda 100HP and by fitting the same calipers I would also have better (let's say sporty) pads available. Thanks koalar for your eper knowledge, can I then ask you if the calipers on a Panda 100HP will fit without further modification on the 1.2 4x4 69HP?
That makes good sense.
The only time I've experienced brake fade in a road car was coming down the Bealach na Ba. Descending 2000ft of steep terrain using the brakes to keep the speed under control puts way more energy into them than just stopping from 70mph. Serious brake fade on a long downhill can leave you in real danger of being unable to stop, hence the need for overrun areas. There's a reason for those signs at the top which tell you to engage low gear.
I'm still not convinced that another 10% of metal in the discs is going to make that much difference; my suggestion is that you keep in low gear and let engine braking do most of the energy dissipation.
If you really are going to try this, I'd be surprised if you didn't need to also change the reaction frames, and I doubt 13" wheels would clear the calipers.
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We all (should) know that brake fade happens when brakes overheat. A long downhill at relatively slow speeds will overheat any brake. The kinetic energy to be dispersed is the same so it’s all about heat dissipation. Bigger discs won’t be any better at that than smaller discs. Bigger vented discs help a bit but only when turning fast enough to throw hot air out of the disc edges. A 10% bigger disc will get hot just as fast because nothing that really matters has changed. You also get worse wheel control as the higher unsprung weight causal more wheel bounce over bumps.
This video explains normal information on the subject and he links to one (also correct) that got many contributors frothing.
This video explains normal information on the subject and he links to one (also correct) that got many contributors frothing.
vexorg
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Basic physics would evade you here, bigger discs must take longer to heat up. And the edge will be spinning faster so will cool slightly quicker.
Every part of the 1.3d 4x4 front brake system is different to the 1.2 4x4
Servo
Master cylinder
Callipers
Hubs
Abs pump
Pads
I can’t find the carrier part numbers
I think first we need to define what we hope to accomplish
Brake fade often used to describes two separate and different problems
First you have to push the pedal really hard because gasses build up between the pad and disc
Second the pedal sinks further to the floor due to the brake fluid boiling
It’s often counter intuitive as to the effects changing parts. I believe the wider discs are due to being vented. Which have less mass so at slow speed might make the problem even worse.
Boiling brake fluid for example could be as simple as changing the fluid and/or adding titanium sheets to the back of the pads
Modern cars rarely have a problem with brake fad unless pushed beyond there capabilities. Even on long descents. Unless the bake is constantly being pressed or the brakes are binding.
Servo
Master cylinder
Callipers
Hubs
Abs pump
Pads
I can’t find the carrier part numbers
I think first we need to define what we hope to accomplish
Brake fade often used to describes two separate and different problems
First you have to push the pedal really hard because gasses build up between the pad and disc
Second the pedal sinks further to the floor due to the brake fluid boiling
It’s often counter intuitive as to the effects changing parts. I believe the wider discs are due to being vented. Which have less mass so at slow speed might make the problem even worse.
Boiling brake fluid for example could be as simple as changing the fluid and/or adding titanium sheets to the back of the pads
Modern cars rarely have a problem with brake fad unless pushed beyond there capabilities. Even on long descents. Unless the bake is constantly being pressed or the brakes are binding.
OP
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TL100HP
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Brake is a torque, therefore bigger discs will always outperform smaller one on multiple stoppages.
OEM system can block the tyres, yes, but no after 5 km downhill.
The second main advantage for me will be the availability of better pads (e.g. ferodo DS2500) that will definitely help in reducing the face on the long runs.
Koalar, thank you again. Last question: is the centre distance between the caliper (1.2 and 1.3 mjet both 4x4) holes the same?
OEM system can block the tyres, yes, but no after 5 km downhill.
The second main advantage for me will be the availability of better pads (e.g. ferodo DS2500) that will definitely help in reducing the face on the long runs.
Koalar, thank you again. Last question: is the centre distance between the caliper (1.2 and 1.3 mjet both 4x4) holes the same?
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Is it plug and play, no idea
Comp. M10 V12 is the 1.3D 4x4
The Panda Nut
Nutty about Pandas Infected by Panda virus and OPD
The only time I have experienced severe fade was with the wrong pads fitted. The effect of this was dramatic and scary. It does show how much pads can affect things. I think maybe some cross drilled discs and harder pads would improve things better and agree with the other suggestions particularly on fluid changing more often. Its worth trying as its a more reasonable cost to experiment and unlikely to cause anything to be worse. If it works job done and if not its not a damning cost.
How about better (fresh) brakefluid? I use ATE Racing (different name now) and never any fading (even when towing a boattrailer over the Alps).
gr J
gr J
Aye, my initial thoughts were fresh DOT4 (maybe even DOT5?) and decent pads.
I used to use EBC Greenstuff pads on my MX5 with occasional track day use, not sure if they exist for Pandas?
I'm surprised a car as light as a Panda with ventilated discs has brake fade. Makes me think something's not right.
I used to use EBC Greenstuff pads on my MX5 with occasional track day use, not sure if they exist for Pandas?
I'm surprised a car as light as a Panda with ventilated discs has brake fade. Makes me think something's not right.
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Correct
We need to know if
It’s pushing the pedal hard it’s not stopping
Or
The pedal sinking to the floor
Once the fluid boiled it needs changing anyhow
