Which brakes to go for ?

[Alzak]

Hi All

Just need some help/advice on which brakes to go for for my Leon FR choice of :

Standard discs with either mintex M1144 or DS2500
NQSBBK on 312mm discs
RS3 calipers with R32 discs

Car is used 100% on road with no track days planned.

[th3_f15t]

What sort of power are you running, or are you planning on going up on power at any stage from what you run now?

[omeydz]

Got R32 345mm OEM setup Front BBK for sale £350 ono if your interested? Pics in my for sale thread and freshly painted gloss black. Sorry for this cheeky post ! 

[Alzak]

What sort of power are you running, or are you planning on going up on power at any stage from what you run now?

Dont really understand what this got to do with my brakes ?

I want to improve braking distance so power atm or future mods are irrelevant ?

Standard brakes on FRs are 312mm front and 256mm rear in my opinion their performance is poor but this may be the case of std road pads and disc used in this application.

I want to improve braking distance but nothing OTT ...

[abdulc]

What sort of power are you running, or are you planning on going up on power at any stage from what you run now?

Dont really understand what this got to do with my brakes ?

It has everything to do with your brakes.

If you don't think so then upgrade your pads, fluid and hoses and call it a day.

I'm guessing as you didn't bother answering the question you drive a diesel? Lol

[th3_f15t]

People will need to know what power you're running (stock, stage 1 ect.) as the kit people would recommend depends on current power and future plans.

If running stock power and keeping it that way, go for some good discs, pads, stainless steel lines and fluid.

If you're going for stage 1 or 2, get the NQSBBK as this will cope better with the increased torque/BHP.

I personally run a 266 BHP / 305 ft/lb torque GTI with a simple 345x30mm big brake conversion (from a mk6 Golf R in my case) on the front and the stock 288mm discs and pads out back. When I go up to stage 2 levels of power/torque I'll look to invest in a 4 or 6 piston front caliper with much better and lighter discs for improved performance.

[Alzak]

People will need to know what power you're running (stock, stage 1 ect.) as the kit people would recommend depends on current power and future plans.

If running stock power and keeping it that way, go for some good discs, pads, stainless steel lines and fluid.

If you're going for stage 1 or 2, get the NQSBBK as this will cope better with the increased torque/BHP.

I personally run a 266 BHP / 305 ft/lb torque GTI with a simple 345x30mm big brake conversion (from a mk6 Golf R in my case) on the front and the stock 288mm discs and pads out back. When I go up to stage 2 levels of power/torque I'll look to invest in a 4 or 6 piston front caliper with much better and lighter discs for improved performance.

I'm running stage 2 atm with possibility of going for GTB turbo within next year or so .

Don't really get what power got to do with requirement to stop quicker in a city driving but is probably just me ... in my opinion even car with 1.2 enginer should have best available brakes (but not an overkill) as this is what may save you in case of emergency ... most of car manufactures do not spend more than they have to simple as.

[th3_f15t]

When you're breaking, you're turning the kinetic energy of your vehicle into heat energy by braking. The kinetic energy of your car comes from the chemical energy release by combustion in your engine.

Basically, the more power your engine produces the more energy it is giving the mass of your car, therefore the more energy the brakes have to transfer to heat when you break.

More horsepower and torque mean there is more energy within the mass of the car when moving that needs to be converted to heat by the breaks. Because increasing the performance of your engine effects every part of the power delivery, you'll most likely need brakes that are better at converting the increased amount of energy, hence the fact that we are all saying your level of engine tune plays a MASSIVE part in your choice of breaks.

Although you're only city driving, when you rev the engine you are producing energy, and even though you may not use the full rev round, at a given amount of revs you are now producing MORE energy because of your stage 2 tuning, therefore brakes are put under more stress regardless of how hard you drive.

I love physics, it's why I'm doing a degree in the subject! Hope this helps you understand why we're nagging you for engine tune specification!

[Chris01]

Nice discussion. What the_fist said sounds very logical, I've also debated upgrading the brakes a couple of times but have never went ahead with it. Like the OP, I'm also doing 90% casual driving in the city however stopping power is one of those things that I'll never have enough of.

When searching for BBKs in the past I've come across performance tests and comparisons with stock kits and in most cases I recall not noticing a huge difference if any at all. The BBKs usually offered a big improvement in brake stamina but almost no improvement in braking distance when both brakes were cool**. In a simple example the 100-0 braking distance would be the same for stock and BBK, but if they did 3 tests in a row (track driving style) the OEM brakes would lose performance much faster than the BBK setup.

Essentially they seemed to be more of an upgrade for the driving style than the engine power, assuming the cars' passive properties (total mass, tire dimensions, weight distribution) remained the same. Of course, physics are always correct and a car moving moving faster overall will need to brake more and also maintain a certain mileage between each brake service.

So it seems that unless you plan to abuse the brakes (or do more aggressive driving), to my understanding there is no significant gain in stopping distance which is what I would be personally looking for.

[SurreyED30]

No point in having 300+ bhp on standard brakes, you'll soon realise when you can't stop in time 
Having all that power and no control over stopping is dangerous mate.

[Alzak]

Surely if i have modified car with standard brakes it will come to stand still within exactly same distance  as non modified car with standard brakes if both cars brake from 60mph ?

[Rayhoop]

Surely if i have modified car with standard brakes it will come to stand still within exactly same distance  as non modified car with standard brakes if both cars brake from 60mph ?

Exactly.

Brakes turn the kinetic energy of the car to heat.  The basic formula for kinetic energy is "1/2x(mass x speed (squared))".  That calculation has nothing to do with how powerful your engine is.

However - the 'speed/velocity' part of the equation is dependent on how hard you press the fast pedal, and the rate of acceleration (which is determined by a) how powerful your engine is (and gearing) b) how heavy your car is)

The relationship between engine power and spec of your brakes comes into play when you consider driving circumstances where you are accelerating hard before you need to brake.  Which is what most people here are eluding too.

A more powerful engine gives you the potential for reaching a higher speed over a given distance (compared to a standard car).  Therefore, in a 'race' situation (or over excited driving on the road), the more powerful car is likely to be travelling faster (more kinetic energy) than a standard car... therefor more heat generated during braking.

The braking system has a capacity for heat.  Once it is reached, you suffer brake fade, spongy pedals etc.
Bigger brakes have a higher capacity and ability to dissipate heat better.

A standard car could probably also cook big brakes etc, but it would require some seriously hard driving and punishment of the brakes.  Alternatively, a 300+hp car could operate fine on standard brakes - assuming you do not drive remotely hard (but push it a little and you can easily find yourself in big trouble when trying to stop).

Bottom line.  If you are not going to be attacking your brakes, trying to brush off big speed repeatedly etc, then a healthy set of standard brakes are probably going to be fine (regardless of engine power).  However if you intend to push your car (standard or modified) and attack the brakes, you are likely to cook the standard brakes - and hence should think about how to avoid cooking them.

Regular basic maintenance (fresh/correct fluid)
Quality pads/discs
Addditional cooling ducts
Upgraded caliper/discs/pads
Parachute
Air brake
Anchor
Reverse thrust...

the options are endless.

Asses your requirements.  Figure out how robust you need your brakes to be.  Make a decision.

However - dont skimp on brakes.  Even if you keep your car and brakes standard, you are talking about a quick car in general... dont use tesco value brake pads (that is not a message to anyone specifically!).

Alzak - I'm in a similar position to you using my car 100% on the road, except my car is standard (edition30) and likely to stay that way for a while.  I'm looking to stick with OEM discs and maybe an upgrade on pads, like the mintex or ferrodo options you mention.  Service the silders etc & finally some fresh fluid flushed through by my dealer should keep them working fine.

I dont find that I drive the car too hard on the road.  Yes I do enjoy it, but it is not sustained abuse lol.  If in the future I find my requirements change, I can upgrade from there if needs be.  But so far, yes they could be better, but the standard brakes work fine for me and I drive accordingly.

If you find you do enjoy driving your car hard, an upgrade of the front brakes might be worth while - espec if you are likely to be running more power soon.

[Alzak]

Many thanks for your reply.

I decided to go for standard discs front and rear, and mintex M1144 pads on front and standard on the back, tomorrow I booked some time in my local garage to investigate noise from rear suspension as soon as this is sorted I get some brake parts on order.

[greygti]

I have standard discs with ds2500 front pads and at 265bhp they can just about cope, next upgrade for me would defiantly be better brakes probably AP 4 pots

[Rayhoop]

I recently did the same as Alzak. Standard discs all round. Mintex 1144 pads up front with standard on rear.  Standard brake fluid to vw spec (ate sl6).  on my otherwise standard Ed30.

I took part in a track day at Bedford in March, on the GT circuit layout and the brakes stood up well to a very good hammering from me and my mate who is a regular track driver and he showed the car little mercy.  No fade, but did get a bit of rumble when they got very very hot.

Im still running them on the road. The mintex 1144 are pretty good from cold too. A little squeaky when cold but not a big deal.