Brake bias... How does it work?

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Seeing that i've opened a forum in the tuning section... I ddnt get much talk on it... I really need to know which works best... The lower numbers (2-3) or higher (7-8 )...
 
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Well lad, it depends hardcore!! Like with all the parts where u can change something u'd have to try out which works best. As i am not an native englishman and do not speak and write perfect, i try to give u some hints and tips on this one:
First of all: Is the car FF, FH or MH? The brake balance is here to optimize the stability of the car during the braking, also the amount of power that is used to make them stop the car brutally.
As an FF car is already quite stabile overall (it pulls the car, makes everything very stabile) you can put more force on the frontbrake, usually i set them 6 front and 5 back for a start with all cars to try it out. As long as the car remains stabile during the brake process u can put it higher and higher, but u have to avoid bumping (happens when u got a suspension which is too hard, set the suspension very hard and try to set the brakes on 10 and look what happens when u brake hard)
An FR has the tendency to oversteer already while braking. In the most FR cars u can use the same settings as above, but if u harden the suspension too much the car starts bouncing, meaning u lose control. Which is more likeable with FR cars. Then u set the balance to F5 R6 to start off.
MH cars got very good balance overall (Elise f.e.) and they react very fast in corners (they mostly are very light), set the balance to F4 and R7, this is what i do for a start.
Overall u could say: if the brakes are set harder to the front, the car brakes much faster, but it is also gettin instabile while braking. If the brakes are set to the rear end, u lose worthfull meters while braking, but u will be very stabile while braking.
Racecars often cannot be set too hard because the suspension ist mostly very hard and the cars light.
There are lots more things to look out for, but since u seem to "start" trying out i guess these are some helpful tips.

Cheers mate
 
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Thanks for the input man! Yes i rarely drive 4wd/awd vehicles due to understeer, and i dont drive ff cars because they're all just too slow.. Thr car specifically im driving is the xanavi nismo gt-r r35 08' in te super gt class... Running with a stage 3
Engine upgrade and stage 2 turbo running the car at 633 hp
 
Good choice man, i really like them aswell! I set the balance to F7 or 8 and R5 or 6, depending on the track.
With the right settings u can also force an 4wd car even to oversteer: (dont know the right words, so i explain where to set what) on the right (i think its called camber angle)
set the front and rear to at least 2 degrees, and the thing down left to -0.20, the camberangle makes the car grip more in corners, the other thing is responsible for the turning. My Subaru Impreza WRX STI '10 corners like a FR car, wonderfull!
Do the same thing with FF cars and they are surprisingly fast, try out the nu Civic!
 
Wasn't the information in the other thread complete enough?
You could have posted a followup message requesting more details.
 
My brother told me that 10 10 was fairly superior and I thought nothing of it until I tried it and it makes a large difference.

I drove an FR car around Tsukuba (ABS 1 all else off, grip edge set to real), first with 5 - 5 for a control, then lowered it to 1 - 1. At 1 - 1, you definitely had to brake earlier in order to stop the car's momentum, and this causes a strange oversteer at first and then an understeer.. really not worth ever having this set up. So then I tried 10 - 10 and sure enough you can take a more aggressive brake line, and it is faster than 5 - 5 because of that, but then you have less speed in the apex and need to rebuild onto your RPMS. So then I tried 8 - 9 (because the car I was using has understeer, I tried to correct for both not killing as many rpms and cause a little bit of oversteer) and this seems to be best for keeping your RPMs high at the apex while still being able to grip the car around a turn fast - and the extra RPMs you can put towards the exit speed really help get ahead of the 10 - 10 setup.

Anyways I think it is track and car dependent, but it seems to change the brake distance and change how you enter a turn, hit the apex, and exit a turn by forcing weight shift. So for example, I probably could do 9 - 9 and still steer the car fast and hit the apex even faster, and just steer more while giving it gas exiting the corner and so long as I stayed on the tarmac it would be better than the 8 - 9. There's probably consequences on your tires for using more brake balance but people seem to like no tire consumption anyways :\

I'm testing it right now with ABS off to see what that's like
 
I'm testing it right now with ABS off to see what that's like
ABS off requires a completely different approach. I suggest you to start trying with a 7/2 brake distribution. We can discuss the details later as you finish testing.
 
Okay so with abs off, 1~10 doesn't make that much of a difference, there is a difference but it's not as similar as with ABS 1;

with 1 - 1 to 9 - 9 it feels like you have to be braking more to hit the apex still, even controlled braking (I'm using DS3 so it may differ with pedals) you still hit the apex later than 10 - 10, and with pressure sensitivity 10 - 10 feels like it gives the most control. In fact, there's no reason to have a lesser number on the front wheels, like 10 - 9 is better than 9 - 10 although both of those still don't feel as good as 10 - 10 without ABS.

0 - 0 is useless, as with 1 - 1 to 9 - 9 simply because you are still able to cancel the momentum for the turn the quickest with 10 - 10. From 6 - 6 to 10 - 10 the car feels almost the exact same though.. except for the fact that the 10 - 10 ghost car was still able to pull away faster than the lower values simply because it was already in the turn accelerating where using a lower value you're wasting your time still braking so you don't understeer your exit.

Akira - 7 - 2 is awful because then you get understeer :P Still though, 7 - 2 is almost no different than 10 - 10 imo, both cars would be able to keep on the same pace.. I suppose though with 7 - 2 you wouldn't have to be first because you could just draft into first anyways though.. still it takes the same amount of skill to be using either setup.. 7 - 2 and you have to be more aware of when/if you need to handbrake, whereas 10 - 10 you have to be controlling your braking properly or else your tires would just lock up.
 
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If words don't help you, go ride a bicycle with front and rear brakes. The brake balance numbers you adjust are essentially how hard you squeeze the brakes.
 
If words don't help you, go ride a bicycle with front and rear brakes. The brake balance numbers you adjust are essentially how hard you squeeze the brakes.

That's not necessarily true because the DS3 and pedals are pressure sensitive, so there's a dynamic range there also.. that pressure senstivity would actually be more like the brake squeeze example.
 
Okay so with abs off, 1~10 doesn't make that much of a difference, there is a difference but it's not as similar as with ABS 1;
What tires were you using, and was Skid Recovery Force activated? Were you pressing the brake all the way down?
I can't see how you could say that there's not much difference with the ABS off.

10/10 with the ABS off (and skid recovery off) means that the rear tires will lock first and almost immediately as soon as you press the brake trigger, with subsequent loss of control.
Check again your settings.
 
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Yes but 1 - 1 they will lock up, not as quickly, but they will still lock up.. the only time they don't is with 0 - 0

My fastest is still with 10 - 10 and just not braking so hard.. just because the tires can lock up doesn't mean you have to be locking them..

Also I say there's not much difference from 1 - 1 to 10 - 10 as in the braking distance, if anything 10 - 10 has the absolute best brake distance because it's not handbraking, if you don't believe me go handbrake and then go use 10 - 10 and brake.. big difference!
 
I don't use ABS and my brake controller is usually something like 3/2 or 3/1 (3/1 more lately for online use, sometimes even 4/1).
 
Corpsey
You're not answering my questions. Car? Tires? Aids?
Also are just trying to brake on a straight line? Try doing 2-3 complete laps on a short circuit and see the difference between different settings.

I don't use ABS and my brake controller is usually something like 3/2 or 3/1 (3/1 more lately for online use, sometimes even 4/1).

By the way, I made a reference chart for brake distribution settings. The first two columns are the brake distribution front/rear in %, third and fourth ones are corresponding GT5 front/rear brake force settings:

PHP:
91.7	8.3	10	0
90.9	9.1	9	0
90.0	10.0	8	0
88.9	11.1	7	0
87.5	12.5	6	0
85.7	14.3	5	0
84.6	15.4	10	1
83.3	16.7	4	0
83.3	16.7	9	1
81.8	18.2	8	1
80.0	20.0	3	0
80.0	20.0	7	1
78.6	21.4	10	2
77.8	22.2	6	1
76.9	23.1	9	2
75.0	25.0	5	1
75.0	25.0	8	2
73.3	26.7	10	3
72.7	27.3	7	2
71.4	28.6	4	1
71.4	28.6	9	3
70.0	30.0	6	2
69.2	30.8	8	3
68.8	31.3	10	4
66.7	33.3	3	1
66.7	33.3	7	3
66.7	33.3	9	4
66.7	33.3	5	2
64.7	35.3	10	5
64.3	35.7	8	4
63.6	36.4	6	3
62.5	37.5	4	2
62.5	37.5	4	2
62.5	37.5	9	5
61.5	38.5	7	4
61.1	38.9	10	6
60.0	40.0	5	3
60.0	40.0	8	5
58.8	41.2	9	6
58.3	41.7	6	4
57.1	42.9	3	2
57.1	42.9	7	5
56.3	43.8	8	6
55.6	44.4	4	3
54.5	45.5	5	4
53.3	46.7	7	6

A short 50/50 FR car like the Honda S2000 under heavy braking (let's say 1G of deceleration) can transfer up to 75% of its weight to the front wheels. Therefore a balanced (or better worded: neutral) brake bias setting would be the one the closest to this ratio. Short FF hatchbacks with a strong front weight distribution bias can under braking transfer even more than 85% of their weight to the front wheels (Reference from which I made a quick spreadsheet to calculate this: http://www.mrfizzix.com/autoracing/weighttransfer.htm). Note that online you get about 75 Kg of extra weight to the back of the car due to fuel load, which can affect "perfect" braking settings.
 
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So you are always putting 100% brake pressure then?

Car - Alfa Romeo Giulia Sprint Speciale '63
Tires - Stock (Comfort Soft)
Aids - None, it's a '63 - although I usually use ABS 1 because I'm using a DS3
For the most part I'm braking in a straight line, but with 10 - 10 you are able to take a more aggressive line. I'm not using tire consumption which is where this probably wouldn't work as well as 7 - 2, are you using tire consumption because that could be where we differ in setting up. I have mentionned
"There's probably consequences on your tires for using more brake balance but people seem to like no tire consumption anyways :\"
If I were racing with tire consumption I would not use 10 - 10 most likely.

This car is not the car from my ABS testing either, for that I was using a stock Caterham, also with no aids then except ABS 1 and no tire consumption.
 
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So you are always putting 100% brake pressure then?
Not with ABS off (0).

Aids - None, it's a '63 - although I usually use ABS 1 because I'm using a DS3[...]
I was speaking so far of settings with ABS 0, sorry, but you're mixing and confusing things together and causing headaches.

For the most part I'm braking in a straight line, but with 10 - 10 you are able to take a more aggressive line. I'm not using tire consumption which is where this probably wouldn't work as well as 7 - 2, are you using tire consumption because that could be where we differ in setting up. I have mentionned If I were racing with tire consumption I would not use 10 - 10 most likely.
My 7-2 suggestion was with ABS off (0).
With ABS 1 you generally have the shortest braking distances with 10-10 as you report, at the cost of a higher tire consumption.

But my posts were referring to ABS off, again.
I currently use a DS3 too, by the way.

This car is not the car from my ABS testing either, for that I was using a stock Caterham, also with no aids then except ABS 1 and no tire consumption.
And I think once again, if it wasn't clear, that I was strictly referring to brake bias values with ABS 0.
No aids usually means no aids, not even ABS.
 
Even with full pedal/button pressure, if you can manage to lock up the brakes at all at 1/0 without any bumps or steering input, you are doing something extraordinary.

EDIT: OK, maybe below 15-20mph it's possible :)
 
Speaking of settings with the ABS off so far I've used 10-1 for FF cars and 9-2 for FR cars as a starting point. This will make front tires lock first at about 50-55% of the brake gauge, and give a generally neutral braking feel.

I have to say, however, that yesterday I spent two hours testing brake bias settings on the Top Gear Test Track main straight (which is very flat) and surprisingly found out that bias that apparently have the same ratio (I tried both with a 10 and 11 values scale - since bias value start from 0 and yet brakes are still effective), work differently. So the chart with the percentages I posted above isn't correct.

As a bias setting of 1-1 gives only marginally better stopping distances than 0-0 (both setting can't lock brakes) eventually I found out that it would probably be better to assume that a brake bias setting of 0 means in reality a base pressure of 4 or 5 and that any setting above that is added to such base value. Bias percentages computed in this way don't make sense at all, but seem to be consistent.


In the end I think it would be better to forget technical details about brakes and simply adjust the front brakes pressure to a value of your likings, and then rear pressure so that when threshold braking from high speeds front tires overheat (and eventually lock) just before rear ones.

My idea is that PD should have provided two different settings for brakes: distribution (bias) and total brake pressure. What we currently have is confusing.
 
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My favorite settings for MR type cars is 3 up front, 2 at the back.

Helps with stability for high speed cars, and helps a little on the tire life.
 
My 3-2 bias works rather well but lighter cars and audi R8's it doesn't lock or it's near impossible.

My times on the deep forest raceway are
F430 1'26.xxx
458 1'24.xxx

The 3-2 bias really kicked in if I went over say 75-80 % maybe more, forgiving but go too far and it locks...just right :D In those cars anyway.
 
It takes some time to get to it...but the Mulsanne Corner is a good place to evaluate your brakes. I like more strength to the front.
 

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