Brake bias, how does it work?

[bullet360]

So.. Im confused... Do you brake better with the "oh so stereotypical 7 front 3 back"... Or with like a 8 front 7 back? Higher power should mean better braking for both but i cant seem to find the perfect spot for the braking tests.. The closeat "full out" braking spot i can only seem to find is the last turn after the long straight on the green hell... But both setups seem to stop in the same location when i come to a complete hault when messing around in my lounge... Yes i know most of you dont like reading books so i'll stop here... Any helpfull input is fine, just as long as its legitamite, constructive criticism.. Nobody is learning anything by calling me an idiot who knows nothing and should just quit racing...

 

[Leonidae@MFT]

Front brakes are usually set stronger due the weight shifting to the front under braking. This presses the tyre harder against the tarmac, allowing harder braking on the front tyres, but as a downside, it will also overload the tyre and might cause understeer when you start turning to the following corner. You have to pay attention to the cars weight distribution as well when tweaking the brake balance, also, camber has a large effect on the stopping powers that the brakes can produce on the contact patch.

In other words.. When you tweak the brakes, you also need to tweak the suspension and LSD to create a car that behaves as you want it to behave when you need it the most, even when it is relatively simple thing such as braking.

 

[thepineapple1]

If the car tends to understeer I'll decrease the front and increase the back, that way when I break in a corner, the front will slide less and will give the impression that the back slides more.

With an over-steery car, I increase the front by a bit. This way if I start to loose control of te car, I just hit the breaks and I know that my car will regain composure.

The amount depends on each particular car & on your handling skills. But you may also choose to change brake bias to save the wheels from being turned into smoke & rubble, in endurance races for example.

I don't know if it's of any significance, but I prefer to keep my total brakes at 10. Let me explain, if I increase the front by 1, I will decrease the back by 1. I believe in keeping the balance.

But you may also turn everything all the way up, in order to break stronger, over a shorter distance.

 

[Leonidae@MFT]

..And then there's the matter of cars that have brake discs make out of old cheese, which won't stop the car no matter how you tweak the balance and other settings.

 

[shirakawaa]

Unless you turn off the ABS, you're not going to notice much the effects of different brake distribution settings, as the ABS driving aid redistributes braking power dynamically (and unrealistically nicely) depending on tire grip while braking.

 

[bullet360]

In other words.. When you tweak the brakes, you also need to tweak the suspension and LSD to create a car that behaves as you want it to behave when you need it the most, even when it is relatively simple thing such as braking.

Pretty amazing how complex tuning brakes can be...

 

[thepineapple1]

Unless you turn off the ABS, you're not going to notice much the effects of different brake distribution settings, as the ABS driving aid redistributes braking power dynamically (and unrealistically nicely) depending on tire grip while braking.

^ Not really true. Since ABS 1 pretty much all it does is keep the breaks from locking up.

On a side note, I like how all cars have Break Bias, even though their real life counterparts only have breaks in the front.

 

[bullet360]

Yeah seeing that the weight shifts pretty significantly when you're going from 190+mph down to 80 in a matter of aeconds during the last straight of the green hell... Im judging by the jgtc (japanese grand touring championship)
Nissan xanavi nismo gt-r 08' with 633 hp... The cars can haul i'll give em that, its just that whenever i change it up... I seem to have the illusion that im improving my brakes everytime i change them... No matter how whacky (or unrealistic) thr setup might be... Thus im judging with a logitch g27 wheel also.... Just to give me that turning sensation the ds3 so lacks of... But the ds3 really helps when the back end steps out randomly, but thats a whole nother story... Keep the feedback comin' and thanks for the help !

 

[Leonidae@MFT]

On a side note, I like how all cars have Break Bias, even though their real life counterparts only have breaks in the front.

As a mechanic I don't buy this. Source of this statement?

 

[shirakawaa]

^ Not really true. Since ABS 1 pretty much all it does is keep the breaks from locking up.

This doesn't contradict with what I've written. Since the godly GT5 ABS aid avoids tire locking in all conditions (something that real ABS systems aren't able to do, since they are emergency safety systems rather than aids for sports driving), setting up different braking distribution values with it isn't going to provide much difference in driving behavior. The story is totally diferent if you disable it, where you just have to start from front-biased settings (for example 5/1) and from there you can make the rear axle of a car much more reactive under braking by slowly increasing rear brake power.

 

[Leonidae@MFT]

GT5 ABS isn't really that godly, as the tyre will still overload and lose grip.

 

[shirakawaa]

GT5 ABS isn't really that godly, as the tyre will still overload and lose grip.

Compared to real systems it is. It doesn't work in impulses and is able to brake at the tires' maximum grip threshold. It also works excessively well as a dynamic stability control aid under braking. You can't safely approach corners while braking like it's possible to do in GT5 with the ABS enabled in real life.

 

[Dragonthing]

I generally have most RWD cars setup for around a 4/7 split, mainly because too much front can cause the back to slide out. On FF cars like my Kei cars I usually go for something around 10/2 or 10/3, because they have plenty of weight at the front so the rear won't slide.

 

[Mudd]

IMO, from various tests, the default brake setting of 5/5 is stock veh setting, which means the bias is already more in the front (around 70% front, 30% rear). The bias adjustment doesn't "increase" the braking power, but simply adjusts the sensitivity of the braking from front to rear, allowing you to use more or less brake pedal to achieve the same stopping distance. Adjusting the front or rear setting individually is purely for changing how the car handles while braking into corners. No matter what your bias settings are, if you apply the brake pedal to 100%, your brake power is 100%. By increasing bias to 10, your not actually getting 200% brake power, your only achieving 100% sooner as you push the pedal down.

 

[shirakawaa]

Now try with ABS off and you will see that the 5/5 stock setting will cause massive oversteer when braking, meaning that in this way the bias is truly 50% - 50%.

As I mentioned previously, with ABS enabled the brake bias setting loses most of its meaning, inducing only a slight hint of oversteer (or understeer) with extreme settings. This is because the ABS in GT5 in its magnificence (not only it's the most efficient ABS on Earth, it also includes EBD and some sort of active stability control working only while braking) efficiently redistributes dynamically brake power as fit in order to avoid tire locking and loss of control.

You're right though that increasing brake power doesn't mean that stopping distances will be proportionally shorter, although with the ABS enabled some people have tested that a 10/10 bias setting yelds the shortest braking distances (this is a neat trick in certain licence tests to get Gold).

 

[Mudd]

Now try with ABS off and you will see that the 5/5 stock setting will cause massive oversteer when braking, meaning that in this way the bias is truly 50% - 50%.

I agree with your comments on unrealistic abs, but still don't believe that a 5/5 settings is a 50% equal split in brake bias. I think the massive oversteer is purely due to all of the veh weight shifting off the rear axle during heavy braking. If the bias were 50-50, then when the weight shift under braking occurs, the rear wheels should instantly lock up and the car would be completely uncontrollable. There wouldn't be enough weight on the rear wheels for any grip whatsoever.

 

[shirakawaa]

To put it more clearly, what I meant is that in GT5 a 5/5 setting is a 50% equal split in brake bias only if you turn the ABS off (in this case under hard braking, rear wheels do lock up before the front wheels due to the weight shift, with almost complete loss of control - the massive oversteer I mentioned).

With the GT5 ABS enabled, it becomes just a starting point for the car's EBD (electronic brake distributor) which acts dynamically and very quickly under braking and this is why I've been writing all along that as long as the ABS is enabled the brake bias setting doesn't have a very noticeable effect on the car behavior while braking, except when using extreme settings.

I guess the reason why PD put a standard 5/5 setting for all cars is that they thought that their perfect ABS implementation would have avoided them much research work (gear settings, suspension settings and torque/power charts are relatively easy to find even without contacting manufacturers directly... but what about brake bias?).

 

[Mudd]

I guess during my brake balance testing, I really wasn't looking for what the actual split was, but only testing for how the balance adjustments effected my test veh. I can't honestly say I've ever set it to 5/5 with 0 abs, so I really shouldn't comment on it further. I'll test your example next chance I get, and see it for myself. Thanks for sharing your findings.

 

[CynicalDriver]

On a side note, I like how all cars have Break Bias, even though their real life counterparts only have breaks in the front.

I've seen horrible ideas (disc front, drum rear; drum front, disc rear {aftermarket car}) but never a car having front brakes only. The only possible exception to this MIGHT be a three-wheel car, but logic would dictate the brakes are in the rear.

Just because it is not a setting that you can change, does not mean there isn't a "stock" bias level. The bias is just a word for the F/R braking ratio. You can change this by upgrading the braking system, which is something I would like to see implemented in GT6. I feel that is one MAJOR hole in the tuning of cars in GT5...

A stock RX-7 from 1987 would have far less effective brakes than one which had an aftermarket (quality, not cheapo) system installed. At the same time, a stock 1970 Challenger will have less effective braking than a stock 2011 Challenger. The technology has changed drastically, and should be reflected in-game.

 

[Adrenaline]

As I mentioned previously, with ABS enabled the brake bias setting loses most of its meaning, inducing only a slight hint of oversteer (or understeer) with extreme settings.

100% disagree. I find that the Brake Bias can create very noticeable effects to not only overall handling characteristics, but tire wear over longer races. I'd almost be so bold, to say that anyone who doesn't think brake bias is an extremely valuable tool, can't drive consistently enough lap to lap, to effectively measure it's benefits. ABS at 1.

 

[shirakawaa]

I don't deny that they have a certain effect on handling while braking (I did use myself a strong bias to the rear with ABS 1 during the Subaru seasonal expert race to help the car turn better), but as I mentioned previously, try playing with it at ABS 0, and then ABS 1. You will find out that at ABS 0, settings will have a much more noticeable (and consistent, since they're not "fighting" with the EBD) effect on handling than with the ABS enabled, to the point that a finer tuning would have been welcomed.

To tell the truth PD should really have subdivided the setting in "brake force" (for example in kN) and "brake distribution" (in %) in my opinion.

 

[nomis3613]

Wow, this is a really interesting thread!

I totally agree with everything SHIRAKAWA Akira says. Here's my thoughts about braking in GT5:
1) ABS very quickly activates to hold their tyres at (or very close to) maximum braking. Therefore brake bias only matters for the very small amount of time between the brake being applied and ABS being triggered.
2) Having said that, I sometimes find that high rear brakes does give the car slightly more agility in braking. But it's only having an effect at the very start of braking.
3) As for the actual strength (eg 4/3 vs 8/6), it is just the amplification of the controller input. Higher strength triggers ABS (or locks the wheels) at lower braking percentages. The reduction in stopping distance of higher settings are because there is less delay until the ABS triggers.

Just my 2 cents.

 

[bullet360]

The games advice only shows how to encourage or disable oversteer or understeer, thus not helping with the main fact of braking itself... So theres a pretty slim chance that all of us can be wrong but, really this helped a lot. I always thought a lower ratio (2-3) would be more affective than a ratio that is lets say (7-8 ). They also say a higher back wil introduce oversteer and a higher front will do understeer, but how different and effective is the bias when they are met equally at 2 as apposed to 8?

Once again Great feedback !

:EDIT: i alway asumed they were running what they were running in the LSD section where its pretty much stated... Less is more. So thats where i got the idea of having a lower bias

 

[shirakawaa]

A very confusing thing in GT5 is that the brake balance setting controls both bias and power. To add insult to the injury, its scale starts from 0, so it's really 11 different values for each axle. Also, even with 0 there still is some braking power available.

Anyway back to your question: 2:2 and 8:8 would both be a 50% bias F:R, but with the latter, tires would start locking (with ABS off, rear tires would lock first) with very little brake pedal/trigger pressure. On a front wheel drive equipped with comfort soft tires, usually with a 5:2 bias setting it takes about 70% total brake pedal/trigger pressure to lock front tires. With front braking power of 4 or less, with ABS off, especially if better tires are fitted, you might never lock those tires (and therefore not obtaining the maximum stopping power from them).

It's assumed that 3:1 (in reality 4:2, since the scale starts from 0... but let's ignore that for now) is meant to represent a 75%-25% bias with a total braking power of 4 (abstract scale); 5:2 would be a 71.4%-28.6% bias with a total braking power of 7, and so on. By the way, you can see that the lower the numbers, the less precise becomes bias adjustment. Another reason for PD to split the setting in brake bias and brake power...

 

[ford_racer]

This may have been said before, but it's worth mentioning again.

The tuning option for brakes is for adjusting it's braking pressure, not the brake bias. As SHIRAKAWA noted above, 2:2 and 8:8 are the same bias, but they are different pressure.

Pressure is how hard the pistons inside the caliper move the pad to engage the disc (or the cylinder moves the shoe to engage the drum in drum brake systems) when a certain amount of brake fluid is moved. With higher pressures, more fluid is moved at a quicker/harder pace, generating more braking force sooner. A setting of 8:8 would be 4 times stronger than a setting of 2:2, and therefore 4 times more likely to lock up the brakes.

To find your bias, take both numbers of your setting and add them together. Then take one number and divide it by the total, and that is the bias for that number.

For example, if you have a setting of 7:4, the total is 11. Take 7 and divide that by 11, and you get 0.636363, or 0.64 when rounded. This means the front brakes are carrying 64% of the braking responsibilities, and therefore the rears are at 46%

With a setting of 5:9, you get a braking bias of .35714, or 36% front bias, and therefore 64% rear bias.

I hope this helps with some peoples understanding of braking power vs braking bias.

 

[ford_racer]

This may have been said before, but it's worth mentioning again.

The tuning option for brakes is for adjusting it's braking pressure, not the brake bias. As SHIRAKAWA noted above, 2:2 and 8:8 are the same bias, but they are different pressure.

Pressure is how hard the pistons inside the caliper move the pad to engage the disc (or the cylinder moves the shoe to engage the drum in drum brake systems) when a certain amount of brake fluid is moved. With higher pressures, more fluid is moved at a quicker/harder pace, generating more braking force sooner. A setting of 8:8 would be 4 times stronger than a setting of 2:2, and therefore 4 times more likely to lock up the brakes.

To find your bias, take both numbers of your setting and add them together. Then take one number and divide it by the total, and that is the bias for that number.

For example, if you have a setting of 7:4, the total is 11. Take 7 and divide that by 11, and you get 0.636363, or 0.64 when rounded. This means the front brakes are carrying 64% of the braking responsibilities, and therefore the rears are at 46%

With a setting of 5:9, you get a braking bias of .35714, or 36% front bias, and therefore 64% rear bias.

I hope this helps with some peoples understanding of braking power vs braking bias.

 

[Peter.]

Brake bias always matters. It's the force of the brakes on the front and the rear. ABS or no ABS, it'l always have an effect during braking, on the car's characteristics.

 

[CSLACR]

Wow, this is a really interesting thread!

I totally agree with everything SHIRAKAWA Akira says. Here's my thoughts about braking in GT5:
1) ABS very quickly activates to hold their tyres at (or very close to) maximum braking. Therefore brake bias only matters for the very small amount of time between the brake being applied and ABS being triggered.
2) Having said that, I sometimes find that high rear brakes does give the car slightly more agility in braking. But it's only having an effect at the very start of braking.
3) As for the actual strength (eg 4/3 vs 8/6), it is just the amplification of the controller input. Higher strength triggers ABS (or locks the wheels) at lower braking percentages. The reduction in stopping distance of higher settings are because there is less delay until the ABS triggers.

Just my 2 cents.

I disagree with the bold part.
You can tune a cars brakes running ABS to over-steer, under-steer, or be neutral all through braking.
You can make them spin like a top with ABS if you want, or dive straight into a wall.

 

[bullet360]

Okay... On tokyo r246 the first corner.... Me and a friend both hit the brakes at the same time... Both Our abs is on 1, but his brake bias is equally at 5 and mine are set at 6, but he slowed down quicker to make the turn easier... How does this work? We both were in Super gt nissan gt-r's, him in the xanavi nismo 08' and me in the calsonic, both weigh the same but we were running stage 2 turbo's and were runnig at 630hp. Neithr of us mess with the LSD. So throw that equation of de-acceleration out

 

[bullet360]

Now try with ABS off and you will see that the 5/5 stock setting will cause massive oversteer when braking, meaning that in this way the bias is truly 50% - 50%.

As I mentioned previously, with ABS enabled the brake bias setting loses most of its meaning, inducing only a slight hint of oversteer (or understeer) with extreme settings. This is because the ABS in GT5 in its magnificence (not only it's the most efficient ABS on Earth, it also includes EBD and some sort of active stability control working only while braking) efficiently redistributes dynamically brake power as fit in order to avoid tire locking and loss of control.

You're right though that increasing brake power doesn't mean that stopping distances will be proportionally shorter, although with the ABS enabled some people have tested that a 10/10 bias setting yelds the shortest braking distances (this is a neat trick in certain licence tests to get Gold).

So with your statement... EVERYBODY thats racing online in gt5 has the exact same braking power, But the bias differentiate's the driver on who stops first? Saying if everybody had the same car, same weight and same tyres?