No Brakes!!

[nomis3613]

However. The breaks do not directly stop a moving vehicle any more than the interface between your eyes/brain/foot or the break peddle/piston/fluid/piston/caliper/etc (you see what I mean?)

True, but the braking performance is determined by the weakest link in the chain. It all comes down to this:

As long as your current braking system is capable of locking up your tyres then increasing rotor size and/or fitting more powerful calipers will not stop you quicker. As long as your tyres are locking then they are your limiting factor not your tyres...

But in the real-world is not always the tyres that are the weakest link. More on that in the rest of this post.

----------

I've had another read of Scaffs posts and references, and I agree with most of it, but there's a few things I have different view on:

Source - http://www.stoptech.com/tech_info/wp_brakebiasandperformance.shtml

and

http://www.stoptech.com/tech_info/The Physics of Braking Systems.pdf

Both these sources are about (very ideal-world theoretical) calculation of brake bias, so they're not really meant to be used in this debate about whether brakes or tyres are the limiting factor in braking.

“You can take this one to the bank
...
using stickier tires is ultimately the only sure-fire method of decreasing stopping distances.”

The quote is included on the site as an introduction to the importance of correctly setting brake bias, I don't think it should be read into for other meanings. And the "sure-fire method" bit isn't necessarily saying that there aren't other factors (like bigger rotors) that affect braking performance.

Q - Where can I find test data on stopping distances?
A - At the speeds that stopping distance is generally measured from (60 to 70mph), the test is primarily testing the tire's grip on the pavement. As delivered from the manufacturer, nearly all vehicles are able to engage the ABS or lock the wheels at these speeds. Therefore, an increase in braking power will do nothing to stop the vehicle in a shorter distance. For this reason, we do not record stopping distances at this time. The Brembo systems will show their greatest advantages when braking from higher speeds, or when tasked with repeated heavy braking. The increased braking torque provides for maximum deceleration at speed, and the ability to absorb and quickly dissipate the intense heat generated during repeated braking insures that the braking system will perform at the same high level each time.

These speeds are much lower than you'd see at a race track, so it's not really relevant IMHO. Speaking to a guy who does ABS calibrations for a living, I'm told most standard cars (eg the Civic in GT5- before you upgraded it) will suffer brake fade in a single stop from 200 km/h. So upgrading the brakes would help for this case. Even more so once you start upgrading tyres, this puts the potential deceleration above what the brake system can provide.

And the ABS guru also reckons bigger rotors/piston area/pads often DO reduce stopping distance for even a single 100-0km/h stop. This is because even though the max deceleration is limited by the tyres (and some other stuff that's not relevant to this thread), the upgrades allow peak deceleration to be achieved quicker (eg shorter transient after you hit the pedal). Since the car is travelling fastest at the start, small changes (to how quickly that peak decel is reached) have big effects on stopping distance.

I reckon the reason Brembo don't acknowledge this is because it would require a re-calibration of the ABS system to obtain the benefit. The context of the article is about bolting on bigger pads, rotors etc so they are just trying to highlight that the main benefit is consistent performance over the race duration.

But anyway, according to what I've been told, benefits of upgraded pads/rotors/pistons DO physically exist for fade-free stops.

Assuming that there is adequate traction (friction) between the tire and the road to accommodate the driver’s braking request, the tire will develop slip in order to react the torque found in the rotating assembly

....once again clearly stating that the limiting factor in determining stopping distance (in a functioning braking system) is the road / tyre interface.Scaff

I think the source is being taken out of context. This isn't doesn't prove anything about the tyres always being the limiting factor, it is just talking about slip speed being required to decelerate the car.

Nothing road legal is going to do it, even the track-day biased stuff, pretty much most racing rubber can still be locked up in a single stop.

Maybe for some racing series (lightweight and not much aero), but this doesn't hold true when you start adding weight or aero.

You have not taken into account that with bigger pads and discs you have more unsprung weight, the rotational mass of the rotor itself has increased, meaning more force is required to 'stop it'.

According to my calcs, the rotational inertia is roughly
discs: 0.2kJ (assuming mass 4x 7kg, rotor CoG 200mm, tyre radius 350mm
compared with
car: 1302kJ (assuming mass 1500kg, speed 150km/h)
Which is insignificant I reckon.

Disclaimer: Please understand that my arguments are nothing personal, just different opinions/information. Thanks for the discussion so far! I spose I should finish by agreeing that none of this is modelled in GT5 (so my points are all moot...)

 

[Jack002]

I've raced the Buick Special. Sure it has power, and I took all the weight out I could and added all the power I could. The brake issue is not really an issue. The car is like a pig on stilts. Just because you have a huge engine, that's not all there is to having a fast car. Its simply too heavy to function like a race car. You can't take an old granny car from '64 and mod it into a F1. Its just not gonna happen.

The shelby cobra is like that a lot. Its got uber power and just can't stick to the road. Other cars with better aerodymanics are just passing it like its not even going. The VW beetle would be great to get it going over 75mph, all the power mods and its still puttering along. There are limits to the mods for the cars. The difference between GT5 and real life is that you can further mod a real car than you can these. Its just a fact.

Its no different than the way it was in GT4.

Now why I can't set ratios in every gear of a transmission, that's a mystery. We were able to do that in GT4.

 

[Machate-man]

THE Answer
It is true that you are limited by your tyres, but the faster you are going, the lower the possibility of weak brakes locking your wheels. Meaning that:
Faster AVG Speed=larger brakes needed👍

 

[kilttraeger]

<silly bold colored statement #1 removed>
It is true that you are limited by your tyres, but the faster you are going, the lower the possibility of weak brakes locking your wheels. Meaning that:
<silly bold colored statement #2 removed>

In-game (and that' what we are supposed to be discussing here) - irrelevant.

 

[devianc]

There are two different arguments going on here; apples vs. oranges really. One side is claiming you need bigger brakes to **lock the tire quicker**, or rather supply enough force to do so quicker. This may seem trivial in the milliseconds at slow speeds, but can last significantly longer when entering a chicane at 200mph.

And the other side is claiming...

you need better tires to **stop the car sooner**. This part of the deceleration only occurs once the brakes have approached their braking power limit.

Effectively, both arguments are true, and having both will achieve the end result better together, than individually. Although, you can't use one to seriously win the argument over the other.

 

[budious]

Much of this is dependent on how the suspension is setup. A stiff setup has less grip which translates to less resistance and faster lap times but it doesn't hug the corner nor brake as well. Soften the dampers one notch makes braking distances shorter and gives more traction on accelerating if your tune also suffers from excessive tire spin.

 

[nomis3613]

There are two different arguments going on here; apples vs. oranges really. One side is claiming you need bigger brakes to **lock the tire quicker**, or rather supply enough force to do so quicker. This may seem trivial in the milliseconds at slow speeds, but can last significantly longer when entering a chicane at 200mph.

Hi devianc, actually I don't think you've summarised my argument correctly. Grippier tyres will always improve stopping distance, no question (as long as the brakes are up to the job, which they are in GT5). My argument is that IRL brake upgrades improve stopping distance, mainly for repeated stops but there is also a benefit in single stops.

Soften the dampers one notch makes braking distances shorter and gives more traction on accelerating if your tune also suffers from excessive tire spin.

Hi budious, my experience is that dampers the effect of dampers varies heaps according to the situation. I agree with you when the braking area is bumpy, but in general changing the speed of the weight transfer doesn't necessarily reduce braking distances.

 

[budious]

Hi budious, my experience is that dampers the effect of dampers varies heaps according to the situation. I agree with you when the braking area is bumpy, but in general changing the speed of the weight transfer doesn't necessarily reduce braking distances.

Well I should really say that exception exists only when the car is very well tuned and perhaps resting on a threshold of optimal dampers at the level below, but the next click up appears have a speedier touch to it, but also an increase in braking distance. Say optimal might be damper 5.5 if such existed, simply saying 5>6 in such a very limited case.

 

[nomis3613]

^ fair enough, yeah I tend to agree. Thanks for clarifying!

 

[sk0pe]

The end of the discussion is, There is no brake fade modelled in GT5, hence NO need for brake upgrades.

Brake upgrades reduce brake fade, no brake fade then no need to upgrade.

It would be a pointless upgrade that would exist purely to satisfy your mind that you can stop better without actually having any in-game effect.

Real world race situation is a different discussion, but that wasn't what this thread was about, but like all threads it has deviated from the original intention. :

We had some guy write a novel for a post then at the end say, Disclaimer: " Because GT5 doesnt model brake fade then my point is null and void" - This is all he needed to post.

 

[esio trot]

Excellent topic here!

The interface between the tyre and the road surface is the key. Once the rotation of the wheel has stopped (with big or small brakes) then skidding takes place followed almost inevitably by a loss of control (hence abs).

Don't forget that in the real world you have to take into account the effects of gradient, camber (or superelevation) and the coefficient of friction (tyre and road surface materials).

I don't how deep GT5 goes in this respect - guess some skid testing may be called for ...

BTW, excellent explanation of what is going on here scaff! 👍

 

[Schadenfreude13]

So, in summary, In GT5 there is no need for uprated brakes because the 'stock' brakes are capable of locking the wheels at top speed, and brake fade is not incorporated into the game engine.

Also, back in the real world, 16-inch Brembos on a Honda Civic are quite hilarious:

"Look Honey, big bwakes stop Civic fastew..."

Thank you and good night.

Edit: Is that a Nissan March on the right side of the photo?! I thought people only tuned those things on Gran Turismo!

 

[calico]

please can you explain whya moderator has highjacked a thread to get his own point across if bigger brakes didnt stop you quicker why dont they fit tiny brakes on lorries and buses best you get back to school or go and buy some bigger brakes and test them same as what top gear do
i had 288mm brakes on my vr6 golf and by putting 312mm brakes on it it stops quicker it has nothing to do with surface area as thay use the same size pads a bigger brake has a larger diameter and clamping force on a larger diameter slows you quicker
the laws of physics are if your wheels are locked you are not neccesarily slowing down infact if you lockup on grass whilst traveling at speed you can actually gain speed

 

[Schadenfreude13]

please can you explain whya moderator has highjacked a thread to get his own point across if bigger brakes didnt stop you quicker why dont they fit tiny brakes on lorries and buses best you get back to school or go and buy some bigger brakes and test them same as what top gear do
i had 288mm brakes on my vr6 golf and by putting 312mm brakes on it it stops quicker it has nothing to do with surface area as thay use the same size pads a bigger brake has a larger diameter and clamping force on a larger diameter slows you quicker
the laws of physics are if your wheels are locked you are not neccesarily slowing down infact if you lockup on grass whilst traveling at speed you can actually gain speed

Show me a lorry with tiny brakes IN GT5 and you might have a point. The original thread asked why there were no brake upgrades available in GT5, and a perfectly reasonable explanation was given.

 

[budious]

Would you not consider the possibility that every car is now modeled with the appropriate size rotors and calibers front and rear that the car would feature in real life? A brake bias of 5/5 on a car with larger front rotors and six piston calibers would still favor the brake bias towards the front of the car without adjusting the brake bias. The Buick 62 was designed as a drag strip car so I doubt much attention was given to the brakes on the real car.

 

[RU33ERBULLETS]

So in summary, ALL cars in GT5 come with fade free, fully adjustable carbon ceramic racing brakes. To improve braking performance, adjust brake/weight bias, differential bias, tires, aero, spring, damper, camber and toe settings.

 

[Schadenfreude13]

I know this thread is all but dead, but I was thinking about some physics problems today and came across this: http://hyperphysics.phy-astr.gsu.edu/hbase/crstp.html

Notice there's no mention of brake sizes in the article.

 

[kriz25]

First and foremost I apologize for posting on what is now obviously an old thread but after reading it all in its entirety, including the posted reference material, I must say that although I cannot disagree with the statement that the ultimate limiting factor for braking will be traction (i.e. friction between the tires and the road) and that it is up to the brakes to reach that limit I do disagree with your application of physics.

I am not a learned professional, I am a mere student and as such I will openly accept a correction from more learned men, but it seems to me a vital oversight has been committed by all explanations of why brake upgrades do not reduce stopping distance.

Grip is ultimately the limiting factor, yes, but this is only true once the limit of grip has been obtained (i.e. tire lock). This, you refute, has no real bearing on break upgrades since street breaks can lock up the wheels in most modern cars. I have no knowledge in this area so I shall defer to yours. However it seems to me, through simple common sense and basic physics, that the faster the wheels spin the more force would be required to slow them to the point of locking - which, as you have continuously insisted upon, is the upper limit of braking power. Therefore logic would indicate that larger breaks capable of producing more force would reduce the wheels' speed more quickly therefore achieving maximum deceleration faster and thus reducing stopping times. At the moment I am writing this from my phone and so it is hard for me to go back and quote that article from brembo but I do recall it being stated that the size of the brakes offered no performance gain, and I paraphrase, "at the normal testing speeds of 60 to 70mph" but that they would offer the most improvement "at higher speeds or under sustained braking," at line which was very eagerly disregarded.

Now it is true that brake adjustments seem to be going on in the background of GT5 that make all of this irrelevant for the game, seeing as braking performance always appears to be optimal. That does not, however, render my point moot as the original question of the TC was why GT5 neglected brake upgrades and unless my logic is flawed the only real reason would indeed be laziness, since by my logic the advantages of upgrading to racing grade breaks on a tuned street car which can suddenly hit 180mph on a straight would indeed be noticeable without the need for break fade simulation.

Don't get me wrong, I love the game. And I'm not trying to spark an argument. I simply dislike when a mod stomps all over other people in a thread because they have more backing when they seem to constantly avoid any logic that may invalidate their point. And I do say stomp in the sense that you have not been patient as others here have stated but rather rude and brash and if we are all in the wrong then that is no way to impart knowledge. Teach, don't scold. You'll get further.

Cheers!

 

[Maddens Raiders]

Scaff,

This is one of the most informative & educational pieces (thread + sourced material) that I've ever found on the subject of my beloved GT. I don't know how you put up with some of the sophomoric nonsense & woefully uninformed out there, but good Lord you do an fine job. I hope that you are in a comfortable den, sipping tea & playing GT5 atm.

 

[BigE]

I love reading engineering debates. There's the people on one side of the fence who are, let's say less learned, that just apply basic fifth-grade reasoning to a problem, then resort to "nuh-uh!" fifth-grade response when their logic is proved wrong. Then, on the other side, there's the people that actually know what they're talking about because they've studied the problem, but have to over-simplify in order for the less learned side to understand.

The issue is that braking a vehicle is a complex motion-based mechanical engineering system (i.e. dynamics, for those of us with an engineering degree) that requires a linear chain of events that seems "instantaneous". Those that are saying "bigger/stronger brakes stop quicker" are correct, if certain variables are kept on lock-down. Similarly, Scaff and his sources are absolutely right, in that the tire/surface interface is the most critical interface in this equation, again, if we define what it is we're trying to resolve.

The basic misunderstanding here is the difference between "How do I stop the wheels faster?" and "How do I stop the vehicle faster?". Believe me - these are NOT the same question. Ultimately, in the scope of racing, we shouldn't be asking either, because that introduces skidding, which means a loss of control of the car. Without getting into a dissertation on dynamic physics, while the tires are spinning relative to the car, they are *stationary* to the surface directly under them, so the coefficient of static friction is not yet overcome, and you have a very high frictional force at the tire/surface interface. Once that value is reached, and the frictional force is now based on the coefficient of kinetic friction, because even though the tire is no longer rotating relative to the vehicle, the ground *is* moving relative to the tire. The value of kinetic friction is inherently lower than static friction, which means less frictional force is being applied to the tire. Seems somewhat counter-intuitive, but this is another major benefit to ABS - it modulates the wheel braking as to allow as much wheel roll as possible when you stomp on the brakes to allow the car to actually stop in a shorter distance.

We're just comparing the difference between brakes and tires here, so we have to assume a flat, smooth surface, and identical cars. We also have to ignore the negligible weight difference between brake sizes, tire/rubber compounds, etc. Also, the rotational inertia of the wheel assembly itself is negligible when compared to the linear momentum of the vehicle as a whole.

So, larger brake rotors or more powerful pistons, or a combination of both, are necessary if the question is "How do I stop the *wheel assembly* faster?" Larger brake rotors with the same strength caliper will stop a wheel assembly faster, because it is applying a greater opposite moment (force times distance from the hub). Similarly, stronger calipers with the same size rotor will accomplish the same feat. Of course, it should go without saying that there are combinations of both. Rotor and brake pad materials will also affect this equation, because again, it's based on friction - some materials have higher coefficients of friction - both static and kinetic - than others. Rotors that are larger in diameter, drilled, or of different materials also exhibit greater ability to dissipate heat (based on thermodynamic properties of the material, or if the material is the same, based on available exposed surface area of the rotor), so brake upgrades are very beneficial of brake fade is an issue.

RECAP: Upgraded brakes will (a) dissipate heat better, and (b) offer greater ability to stop the wheel assembly.

PROBLEM: We don't want to stop the wheel assembly. We want to SLOW the vehicle, which means we want to CONTROL the wheel assembly.

Here's where tires come in, and why they're more important in the facet of one-time braking than the brakes themselves. A softer rubber compound offers a much greater coefficient of static friction. With the surface being equal, more lateral force can be applied to the tire/road interface before the connection gives way and one slides compared to the other, or skids. Vehicle linear momentum (mass times velocity) is the value we're trying to overcome here. As the weight of the vehicle increases, the greater the braking moment needs to be applied to slow the car down (i.e. better brakes). Keep in mind - we don't want a skid. We want to slow down. In order to accomplish this, we have to have a tire/road interface that is as static as we can make it - meaning softer compound tires. (*Aerodynamics also has a huge impact in braking force, as a higher "downforce" value increases the force normal to the tire/road interface, boosting the frictional force...completely different subject, and we're assuming it is an equal variable)

RECAP: Softer, smoother tires (because all other tire variables are constant) increase the frictional force of the tire/road interface, actually acting as an inertial force to keep the tire rolling under braking.

Both in reality and in this game, the brakes as designed are capable of stopping the wheel assembly, regardless of the vehicle weight - meaning they're designed properly for safety purposes. It is important to keep this little tidbit in mind - we must assume the brakes are not designed to be undersized in the game.

We know now how brakes affect the system, how tires affect the system, let's get back to the task at hand: We're interested in slowing the car, meaning brake *modulation*, or how the applied range of 0% to 100% affects the system. Tire material reduces the overall ability for the vehicle to skid (on a linear basis), regardless of braking power. However, if you increase the braking power, the frictional force at the tire/road interface remains constant. If the car weight is equal, a larger or more powerful brake system will reduce the point along that modulation curve where the frictional force at the tire/road will be overcome, creating a skid. Since we're just wanting to slow the car down, we don't want to hit that point of skidding. If you put more powerful brakes on that brings that point down to, say 65%, you're wasting the rest of your braking power. Once the wheel's stopped, it's stopped.

This modulation curve is variable as the linear momentum (i.e. speed of the car) changes - this is why brakes won't lock up at 100% modulation at higher speeds, but once the car is down to a given velocity, the tires lock up.

SUMMARY: Bigger/stronger brakes will stop the wheel assembly quicker, but offer less modulation for controlled braking. Softer tires will cause the car to slow down quicker, due to the higher friction.

The reality is that you don't necessarily want bigger brakes to slow your car down, because it reduces the modulation capacity of the brakes. When you reduce the modulation capacity of the brake, it brings locking up the tires into play, which is a loss of control. You want the brakes as large as necessary to bring the car to a stop without overcoming the frictional force at the road/tire interface. Assuming different tires but everything else is exactly the same, the softer tires will marginally stop quicker due to greater rolling opposition. However, the softer tires allow for a greater braking force to be applied without overcoming the frictional force, and thereby allow for quicker braking. By the same principle, if we assume more powerful brakes and the same tires, the wheel assembly will stop quicker, which is not what were looking for. More powerful brakes AND softer tires will yield the best results, but due to the scale of the forces at play in the entire system, tires have much more positive effect on the braking system than the brakes themselves.

I guess I have real-world experience in mountain bike racing. Weighing 200lbs, I use a larger rotor than people weighing 150lbs. Has nothing to do with stopping power - a 6" rotor will toss me over the handlebars as quickly as an 8" rotor if modulated to 100%. But the 8" rotor runs cooler under repetitive braking, since it has more surface area to dissipate heat. As such, the repetitive braking is more consistent. Rotor size has nothing to do with stopping power on a one-time braking event...in fact, the 8" rotor is more detrimental, because it will stop the wheel assembly from rotating more abruptly.

IN FINAL: Since heat-based brake fade is not addressed in GT5, and we have to assume the brakes are properly designed for the speed and weight range of the car they're on, any changes in tires will yield more noticeable results in braking distance than the positive effects of the larger or stronger brakes.

 

[mikeonthebike]

please can you explain whya moderator has highjacked a thread to get his own point across if bigger brakes didnt stop you quicker why dont they fit tiny brakes on lorries and buses best you get back to school or go and buy some bigger brakes and test them same as what top gear do
i had 288mm brakes on my vr6 golf and by putting 312mm brakes on it it stops quicker it has nothing to do with surface area as thay use the same size pads a bigger brake has a larger diameter and clamping force on a larger diameter slows you quicker
the laws of physics are if your wheels are locked you are not neccesarily slowing down infact if you lockup on grass whilst traveling at speed you can actually gain speed

I agree with you. If bigger brakes didn't stop you faster we would all be getting tiny little brakes to save weight. The reason the bigger brakes stop you faster is they allow more friction to be applied BEFORE reaching the lock up point.

I've installed bigger brakes on cars in real life and it most definitely decreased stopping distance at both low speed and high speed because we could get more friction applied before the tires gave up.

It's the same reason we put better/stronger back brakes on our stunt bikes (streetbike freestyle). We rely on our rear brake for the tricks we do and with stronger brakes we have more modulation range and strength before reaching that lock up point. From reading this thread I am sure someone is going to try and tear me a new one but this is just what I have found in my learning of brakes over the years and I'll also state that I have about 8 years of working as a full mechanic in repair shops so I'm not just a bar stool cowboy shooting from the hip.

 

[Rotary Junkie]

I agree with you. If bigger brakes didn't stop you faster we would all be getting tiny little brakes to save weight. The reason the bigger brakes stop you faster is they allow more friction to be applied BEFORE reaching the lock up point.

I've installed bigger brakes on cars in real life and it most definitely decreased stopping distance at both low speed and high speed because we could get more friction applied before the tires gave up.

It's the same reason we put better/stronger back brakes on our stunt bikes (streetbike freestyle). We rely on our rear brake for the tricks we do and with stronger brakes we have more modulation range and strength before reaching that lock up point. From reading this thread I am sure someone is going to try and tear me a new one but this is just what I have found in my learning of brakes over the years and I'll also state that I have about 8 years of working as a full mechanic in repair shops so I'm not just a bar stool cowboy shooting from the hip.

Scaff's entire point is that bigger brakes only help when the brakes being used can't lock the tires. Once that point is reached, the only thing that will shorten stopping distances is more grip. (Note: I'm not saying that brake lock is good)

99% of factory vehicles have brakes more than adequate for reaching that point.

So how do you actually shorten stopping distances in that case? Better tires. If the brakes can still lock them, more tire, and so on. Once they can't, more brake. Then more tire. And so on.

As for the "I've installed big brake kits on cars before and it most definitely shortened stopping distances" bit...

Did you test that or are you going off of seat-of-the-pants feel? Were they on OEM or OEM equivalent tires, or better? etc.

 

[calico]

Bigger brakes slow you quicker lock-up is where the brakes are no longer used except to keep the wheels locked. A larger disc area slows the car quicker period hence buses and lorries do not have Mini brakes fitted to them.
If this is not true how do the Audi tt brakes fitted to my golf VR6 slow it down quicker than the standard ones. Standard diameter is 288mm Audi tt are 312mm both use the same caliper and pad so that has nothing to do with it.
If you have never fitted bigger brakes (IE: put your money where your mouth is) then is all you are doing is quoting from other's. A friend of mine has just fitted £1300 worth of brakes onto his golf vr6 turbo and if you dont wear a harness or seatbelt it would put you into the windscreen.

 

[Scaff]

Bigger brakes slow you quicker lock-up is where the brakes are no longer used except to keep the wheels locked. A larger disc area slows the car quicker period hence buses and lorries do not have Mini brakes fitted to them.

Buses don't have Mini brakes fitted to them because a Mini's brakes are not capable of locking the tyres on a bus. One the first and most fundamental part of this is...

As long as your current braking system is capable of locking up your tyres then increasing rotor size and/or fitting more powerful calipers will not stop you quicker.

...but as I have already said, my view is sitting with brake manufactures the world over.

If this is not true how do the Audi tt brakes fitted to my golf VR6 slow it down quicker than the standard ones. Standard diameter is 288mm Audi tt are 312mm both use the same caliper and pad so that has nothing to do with it.

Have you measured the stopping distance of your car? Would you be so kind as to provide the results to us to corroborate that they are stopping you quicker.

However I am sure you can explain exactly how bigger brakes are creating more friction at the tyre/road interface to stop you quicker.

If you have never fitted bigger brakes (IE: put your money where your mouth is) then is all you are doing is quoting from other's. A friend of mine has just fitted £1300 worth of brakes onto his golf vr6 turbo and if you dont wear a harness or seatbelt it would put you into the windscreen.

I upgraded plenty of braking system in my time, I've also worked on the development and set-up of a number of cars with manufacturers, so I have plenty of experience with this.

In regard to your friends car you seem to be missing the key difference between getting brake force applied and how quickly you stop. It sounds far more like your friend is now able to better apply and modulate the brakes (which is the point of a brake upgrade) that doesn't automatically mean you are stopping quicker.


Now popping my moderation hat on for a moment. Do not ever tell a member what thread they can or can't post in again, doing so to any members is ill advised, doing to a member of staff steps well over what is acceptable here at GT Planet. The only members here who get to control who does and doesn't post are the staff.


Scaff

 

[CyKosis1973]

Bigger brakes slow you quicker lock-up is where the brakes are no longer used except to keep the wheels locked. A larger disc area slows the car quicker period hence buses and lorries do not have Mini brakes fitted to them.
If this is not true how do the Audi tt brakes fitted to my golf VR6 slow it down quicker than the standard ones. Standard diameter is 288mm Audi tt are 312mm both use the same caliper and pad so that has nothing to do with it.
If you have never fitted bigger brakes (IE: put your money where your mouth is) then is all you are doing is quoting from other's. A friend of mine has just fitted £1300 worth of brakes onto his golf vr6 turbo and if you dont wear a harness or seatbelt it would put you into the windscreen.

You're talking about real life Vs a game. In the game you can make those brakes as hard or as soft as you like by adjusting them.

I really don't know why this keeps getting flogged. All brakes on all vehicles, in the game, are capable of locking up the tyres. It's up to you to adjust your settings, in the game, to determine when lockup occurs. There is no brake fade modelled in the game and all brakes on all vehicles are capable, I really don't know what else you could want...

{Cy}

PS - And if you think anybody is going to be foolish enough to part with a grand in cold hard cash, just to prove how a braking system works in a computer game, then you're a chump...

 

[Grayfox]

No the red car is a Honda Civic Type R FN2R, Black car in the background is an EP3 with the white car being an FD2.

I just wish you could add new discs like the slotted or cross drilled(i read that these can help reduce brake fade) just for the looks.

 

[calico]

Buses don't have Mini brakes fitted to them because a Mini's brakes are not capable of locking the tyres on a bus. One the first and most fundamental part of this is...

As long as your current braking system is capable of locking up your tyres then increasing rotor size and/or fitting more powerful calipers will not stop you quicker.

...but as I have already said, my view is sitting with brake manufactures the world over.


Have you measured the stopping distance of your car? Would you be so kind as to provide the results to us to corroborate that they are stopping you quicker.

However I am sure you can explain exactly how bigger brakes are creating more friction at the tyre/road interface to stop you quicker.



I upgraded plenty of braking system in my time, I've also worked on the development and set-up of a number of cars with manufacturers, so I have plenty of experience with this.

In regard to your friends car you seem to be missing the key difference between getting brake force applied and how quickly you stop. It sounds far more like your friend is now able to better apply and modulate the brakes (which is the point of a brake upgrade) that doesn't automatically mean you are stopping quicker.


Now popping my moderation hat on for a moment. Do not ever tell a member what thread they can or can't post in again, doing so to any members is ill advised, doing to a member of staff steps well over what is acceptable here at GT Planet. The only members here who get to control who does and doesn't post are the staff.


Scaff

So ban me then POWERFREAK.

ABUSE OF POWER IS A CRIME AS WELL.

You also need to get your facts straight i dint say you cannot post please read the 1st line slowly then you might understand what i said.please can you explain whya moderator has highjacked a thread

In regard to your friends car you seem to be missing the key difference between getting brake force applied and how quickly you stop. It sounds far more like your friend is now able to better apply and modulate the brakes (which is the point of a brake upgrade) that doesn't automatically mean you are stopping quicker.

So in response to the OP yes bigger brakes help stop the car quicker irrespective of how it is done and that is your own admittance.

 

[Scaff]

So ban me then POWERFREAK.

ABUSE OF POWER IS A CRIME AS WELL.

You also need to get your facts straight i dint say you cannot post please read the 1st line slowly then you might understand what i said.please can you explain whya moderator has highjacked a thread

Strange I've not threatened to ban you at all, however if you keep going in this direction that will be the end result.

Staff telling a member to follow the AUP is not an abuse of power and certainly not a crime here, rather following the AUP and the staff instructions is a requirement of membership. So cut the attitude out right now.

So in response to the OP yes bigger brakes help stop the car quicker irrespective of how it is done and that is your own admittance.

I've admitted no such thing and would appreciate it if you would be so kind as to answer the question you were asked in regard to this. Which is:

"However I am sure you can explain exactly how bigger brakes are creating more friction at the tyre/road interface to stop you quicker?"




Scaff

 

[mikeonthebike]

Scaff's entire point is that bigger brakes only help when the brakes being used can't lock the tires. Once that point is reached, the only thing that will shorten stopping distances is more grip. (Note: I'm not saying that brake lock is good)

99% of factory vehicles have brakes more than adequate for reaching that point.

So how do you actually shorten stopping distances in that case? Better tires. If the brakes can still lock them, more tire, and so on. Once they can't, more brake. Then more tire. And so on.

As for the "I've installed big brake kits on cars before and it most definitely shortened stopping distances" bit...

Did you test that or are you going off of seat-of-the-pants feel? Were they on OEM or OEM equivalent tires, or better? etc.

The first time I installed a big brake kit was 13 years ago, a VHS camcorder on tripod was used for analysis. We painted lines. Stops from 60mph and stops from 100mph were made before and after. The brake upgrade was larger front rotors, I believe they were 6 piston calipers and the rear brake upgrade was replacing the factory DRUM BRAKES with discs and multi piston calipers as well as a Wilwood proportioning valve.

My conclusion was YES the car stopped in shorter distances THE FIRST TIME the brakes were applied as well as the 10th test. I haven't had a VHS video in my possession for quite some to so there is no referring back to my old video for exact difference but it was well over a 30ft decrease in stopping distance from 100mph and a little under 20ft decrease measured from 60mph. And the owner of the car and myself agreed that we got it to stop even faster by more fine tuning of the proportioning valve (brake bias) but no other brake tests were performed as the car began it's track life shortly there after and never looked back at the stock brakes.

Yes the car had better than stock sports tires on it with more grip. NO the tires were not installed right after brake upgrade. The car was already wearing 17" wheels with 225/45/17" fronts and 255/40/17" rear. The difference in sidewall aspect ratio number was to attempt to get near the same rolling diameter front to back. Lastly YES the car COULD lock the stock brakes if you stepped on the pedal hard enough. The problem was the stock brakes would only stop so well in maximum stopping situations before achieving lock up. After the brake upgrade the brakes could be modulated better as a result of larger disc area and more pistons allowing a higher friction point in the brakes before they gave up and said "we can't take anymore we're locking up"

So maybe one could say "NO bigger brakes don't stop you faster, it is actually the better modulation you get from the bigger brakes that allows you to stop faster". But saying the statement above would simply make one look foolish because it is fully a result of the bigger brakes.

And to not leave this open for a bag of worms I will also ad that THIS IS MY HONEST OPINION from my real world exp'.

 

[Scaff]

The first time I installed a big brake kit was 13 years ago, a VHS camcorder on tripod was used for analysis. We painted lines. Stops from 60mph and stops from 100mph were made before and after. The brake upgrade was larger front rotors, I believe they were 6 piston calipers and the rear brake upgrade was replacing the factory DRUM BRAKES with discs and multi piston calipers as well as a Wilwood proportioning valve.

My conclusion was YES the car stopped in shorter distances THE FIRST TIME the brakes were applied as well as the 10th test. I haven't had a VHS video in my possession for quite some to so there is no referring back to my old video for exact difference but it was well over a 30ft decrease in stopping distance from 100mph and a little under 20ft decrease measured from 60mph. And the owner of the car and myself agreed that we got it to stop even faster by more fine tuning of the proportioning valve (brake bias) but no other brake tests were performed as the car began it's track life shortly there after and never looked back at the stock brakes.

Yes the car had better than stock sports tires on it with more grip. NO the tires were not installed right after brake upgrade. The car was already wearing 17" wheels with 225/45/17" fronts and 255/40/17" rear. The difference in sidewall aspect ratio number was to attempt to get near the same rolling diameter front to back. Lastly YES the car COULD lock the stock brakes if you stepped on the pedal hard enough. The problem was the stock brakes would only stop so well in maximum stopping situations before achieving lock up. After the brake upgrade the brakes could be modulated better as a result of larger disc area and more pistons allowing a higher friction point in the brakes before they gave up and said "we can't take anymore we're locking up"

I sound a lot to me like this was a situation in which the stock brakes were not up to the job, particularly the rear drums. If the rears were not doing a balanced share of the job (not uncommon with rear drums) then not all the grip available across all four tyres was being used.

In which case, yes a brake upgrade would make a difference as would the correct adjustment of the brake bias (so often overlooked). The next question would be, do you think fitting even bigger brakes would have continued to make a difference? I strongly suspect not.


Scaff