Brake Upgrade

[aragorn]

They hold their bite for longer, so i dont see how they cant stop quicker.

With standard its:
Wohhh I'm stopping, oh wait, no, no ,no now theyve gone to ****.
Thats what mine are like anyway.

with bigger 4 pciston i imagine its :
Stopping, stopping , ahh, stopping, stopped.

As i said up there, thats ALL down to the pads.

Decent fast road pads wont fade away like that until you get them very hot, whereas generic pads for Mrs Mavis to drive to tescos will bite awesomely from cold then goto **** very quickly.

 

[colicabcadam]

The reason you cannot see any benefits is because you haven't driven a well sorted set of big brakes back to back against your uprated standard setup. People who have had big brake and caliper kits in the past have a habit of it being the first mod on their new/next car.

The brakes on my car are TERRIBLE, through no fault of their own. I have quality fast road pads, dimpled and grooved discs and FULLY braided lines. And yeah I can lock the wheels up but because I can actually drive my car (within reason haha!) I have no confidence in their ability to stop me in an emergency.

It is the opposite of your argument over my car being **** for being FWD, if you are measuring how good your brakes are by how easily you can lock the wheels up then you are doing it wrong. I had G60 brakes on my Mk2 GTI and could lock the wheels at 130mph, but under a fast road situation they were crap in the hands of a competent driver.

Prawn managed to boil the fuid and get a total system failure on my 205 GTI within two miles driving it properly...

my ktm stops just as quickly as my ducati, both have the same front tyre and pads material, the ktm has a 320mm single disc with a 4 piston caliper, the ducati has 2 x 330mm discs and 2 x monobloc 4 piston calipers.........

i have to work the ktm brake lever harder to stop as quick as the ducati, but that's all, initial bite on the ducati is far greater then the ktm, but if i compensate by pulling the ktm lever harder there's no difference

however, if i put super sticky slicks on both bikes, i know the ducati would be able to make more use of it under braking

bigger brakes are good, but they will only stop you quicker if you change other things with it too

boiling brakes within 2 minutes has nothing to do with stopping distance on the road, remember, my discussion is in regards to the first 3 hard stops, after this a bigger brake kit will make a difference

 

[Prawn]

You'd really need to compare the two calipers with identical pads though, and its not clear you've done that? You appear to be comparing your LCR calipers on DS3000/M1177 pads with Jardos on something else?

You're right Kev, I am comparing brake setups with different pads, but surely in your argument about locking the wheels pad choice is irrelavent? surely if one pad can lock the wheels then it's as good as it ever needs to be? based on your argument your theory suggests that once a standard pad can lock the wheels, that uprated pads will also do nothing for stopping power, in the same way as a big brake kit will also do nothing?

 

[aragorn]

But pad compounds act differently when pushed hard. Road compounds tend to overheat and gas out for instance, When you ram the pedal down hard enough to clamp thru the outgassing, the pad just grabs hold of the disk and locks up, a race compound will sustain much higher temperatures for much longer without getting into that state, which is obviously what its designed to do.

A road pad will act quite differently on its first stop when its operating at sensible temperatures than it will under prolonged hard use.

 

[Prawn]

Prawny, what brakes are you running?

LCR brembos up front matey, with braided hoses and eliptically grooved discs from Bill, current pads are Mintex 1177 race pads that come with a warning saying they musn't be used on the public road!

at the back it's on S3 256 vented rears with decent OEM discs and pads. want to upgrade the rear discs and pads soon though.

Needless to say, weighing just 1100kg, and with semi slick tyres, stopping power and late braking really is it's party trick!

 

[superkarl]

I genuinely don't get that with my standard brakes. I regularly come down from 140+* to roundabout speed and they love it. Well, maybe not love it. But they do it.

(*kmph. Honest)

what fluid do you have welly? i know this can make a massive difference based on info thats out there. my fluid is actually standard renault ESP fluid, used out of convenience.
my example of my brakes above is pretty much the same scenario as yours, 140ish kph down to roundabout speed. i dont stamp on them like a lunatic, i ease them in progressively, and whilst initially it feels good, they soon fade to nothing and pedal is near solid and im left with weak and unresponsive brakes for the rest of my drive.

mine lasted prob half a lap of the ring before i really had to start compensating for their lack of bite and power.
ADI was the same. surely towards the end of your session your braking was sooner and sooner. reesys dad was behind me and he said it was very clear my brakes were becoming a problem.

As i said up there, thats ALL down to the pads.

Decent fast road pads wont fade away like that until you get them very hot, whereas generic pads for Mrs Mavis to drive to tescos will bite awesomely from cold then goto **** very quickly.

my brakes are TOTALLY standard. and i thought we were talking about standard. obv an upgrade might increase initial bite, but theres only so much the caliper can do too. im going to consider some upgrades to my standard setup.

You're right Kev, I am comparing brake setups with different pads, but surely in your argument about locking the wheels pad choice is irrelavent? surely if one pad can lock the wheels then it's as good as it ever needs to be? based on your argument your theory suggests that once a standard pad can lock the wheels, that uprated pads will also do nothing for stopping power, in the same way as a big brake kit will also do nothing?

this is what i dont get.

obv an upgrade is going to lock the wheel alot easier, thats common sense, but if your braking right and progressively, then that initial bite and stopping force will last wayyyyy longer than standard. and thats where the improvements and reduced distances happen. because that deccelleration rate is lasting alot longer.

 

[Alex C]

Hello?... a BBK looks better?? lol

 

[S3Zek]

I'm sorry, but I also disagree with just about ALL of the above, all the arguments are based on theory, and as of yet, nobody seems to have posted anything relating to actual experience.

Yes, I get your point about tyres locking, and in theory, if you're locking a wheel then the brake is as good as it needs to be, but what about the way in which standard brakes are able to lock the wheels?

On my standard calipers, in both 288 and 312mm form, with all sorts of pads, I too was able to lock up the wheels at high speeds.

This DOES NOT mean the brakes are as good as the tyres can take though.

The truth is, that in reality, the standard brakes offer very little modulation compared to a big brake kit, you press the pedal at 100mph, not a lot happens, you press harder, not much happens, you press firmly, still not a lot happens, then you utterly STAMP on the pedal, and the wheels lock up. Seemingly, at this point, both frictional and adherant pad behavior stops, and simple hydraulic pressure takes over and literally clamps the discs solid. ****** all use to anyone I'm sure you'll agree.

The beauty of a big brake kit, is the ability to run right on the very limit of a tyres traction without locking up the wheels.

When I brake hard, I actually get tyre squeal (like when cornering) as the tyres are RIGHT on the very absolute limit of what they can cope with. Using the same tyres on 312mm S3 brakes, you get a noticably lesser stopping effort, right before they lock up and the ABS kicks in.

We have proved this point by running the same wheels and tyres on my car with brembos, and Jardos identical car with 312mm S3 brakes. the braking effort from his is nowhere even close to what mine can produce.

Big brakes DO make the car stop quicker.

i personally believe this to be the most true answer with my under standing of the way brakes work but thats just my 10 pence.

 

[aragorn]

karl: The fade you describe is pad fade, and is simply due to pads that arent suited to the task your asking of them.

Fit better pads and the fade you describe will go away.

If the fluid was at fault, the pedal would go spongey.

 

[superkarl]

karl: The fade you describe is pad fade, and is simply due to pads that arent suited to the task your asking of them.

Fit better pads and the fade you describe will go away.

If the fluid was at fault, the pedal would go spongey.

ok. il try that out then.

 

[jojo]

Welly, you need to hold an S3 brake caliper with carriers, and then hold a Brembo GT/LCR Brake caliper, I think there was quite a bit of difference in weight. It's not all about braking performance, it's less unsprung weight I think.

 

[16Klappe]

It probably was pedal fade as well to be fair, especially if it's on the original hoses.

Regardless of tyres, we can all agree that before the pads perform at their best they warm up. You apply the brakes, they warm up and get better and then performance fades as they over heat.

So you are in your S3 on standard discs and pads rolling at 70MPH, you slam on the brakes and the wheels lock and the ABS comes on.

What would you say the time difference is between you slamming the brakes on, the brakes heating and the wheels locking? 3 to 5 seconds? Lets say it's 5 seconds and you've traveled 500 feet before the brakes have started to perform at their best and lock the wheels. Couple that in with the thinking distance of say 70 feet and you're 400 feet down the road already. Couple that with the ABS making the entire setup hot as **** and then the brakes fading, who knows you could be 100/140 feet further down the road than you want to/thought you would be.

Throw a big brake kit on there with instant bite/incredible pads, a much wider vent between the rotor and a bigger surface but keep the same tyres. Regardless of the pads the size of the rotors the better caliper will lock the wheel up MUCH easier and for MUCH longer through it's sheer power advantage, the quicker bite will save you valuable meters post thinking time, and the ABS will be able to do it's job better because it won't be fighting with overheating pads, discs and the iron calipers absorbing all the heat and boiling the brake fluid. Potentially saving you 100-150 feet over an upgraded stock setup, which I can guarantee you would save a LOT of accidents.

It's a no brainer, with brakes "will do" is just not an option. If you are flopping £200 on discs and pads why not spend £250 this month on some calipers, £100 next month on some adapters and £150 on some discs and pads the next and get something which will NEVER fail you.

-

Just done the math, at 70MPH you are traveling 100feet per second so my figures make it look MUCH better than it actually is! You could be 150feet further down the road quite easily.

 

[Prawn]

whilst I see where you're coming from, your distances need rethinking

60mph is 88ft per second!

 

[16Klappe]

whilst I see where you're coming from, your distances need rethinking

60mph is 88ft per second!

Yeah, insert the correct distances and you have got the most convincing argument for big brakes ever. 100 feet per second, if you only knock a second and a half off your 70-0 time (which is EASILY possible) you'll be knocking half a football pitch off your stopping distance!

 

[16Klappe]

YES! 25 minutes of silence, I MUST have actually won an argument!

 

[Hammy999]

I don't understand why there is so much locking up of wheels and activating of the ABS. The best way to stop quickly is to Threshold Brake before the ABS has chance to activate ???

 

[Prawn]

The best way to stop quickly is to Threshold Brake before the ABS has chance to activate ???

this is what I was trying to get at! Not heard the term before, but it makes perfect sense.

 

[Hammy999]

It's a technique that improves your braking performance greatly especially on the track but also works well on the road. I imagine it is what you are already doing if you are not locking your wheels or activating the ABS.

 

[superkarl]

tell us more...

 

[Hammy999]

Here are a couple of links from Google that explain it well.

Threshold braking

Drift Session

I have been lucky enough to have done a fair amount of performance driver training and it is one of the first techniques that are taught.

 

[badger5]

it does make me laugh how people assume with no testing or facts to back it up that bigger brakes stop an s3 quicker than the standard brakes would.

does anyone have a comparison sheet ? a stopping distance sheet ? a video ?

if you are not able to lock your wheels up with the standard brakes then the pads you are using must be crap !!

btw - i have not stated that standard brakes are just as good as a big brake kit after a few hard stops as this will not be the case

if you want to stop quicker you need better tyres, wider tyres and smaller wheels, once you've done this and you can not lock your wheels up, you then need to up the calliper / discs - all round !

Stopping quicked CONSISTENTLY is more apt an arguement for you folks

stopping once from high speed vs repeatedly stopping from speed, heatsoak issues into the components etc etc

weight transfer of the vehicle whilst heavy braking can offload an axle's grip also

Usual progression of improving brakes starts with pads, disks, fluid.... then if you still want more, bigger...