Brake bias - default setup way off?

[RhinomanWC]

As a novice with this kind of stuff, I just drove with whatever the default bias was, but once I had taken SC and ABS off, I found the cars much more difficult to control. I went forward with the bias and that seemed to give me more control and I was no longer getting snap oversteer part way through slow corners. Then I realised that I was just getting slower and slower as I was struggling to make the turn-in. So in the last few days I've pushed the bias back again so that it is now pretty much 50:50 and I certainly find it easier to drive, although on cold tyres at the start of the race I find myself at great risk of spinning like a top in the very slow corners. I've done half a dozen GTE races at Fuji and in three of them I have spun on L1 either at the chicane or at the hard left uphill penultimate corner (which I've always struggled with). Once my tyres have warmed up it's a lot easier. Any more hints and tips would be appreciated.

I have EXACTLY the same experience as you do! Figured I just needed more practice. On the plus side, since I've turned off stability control I'm learning to catch slides better especially at Fuji. Thanks for requesting help with this and thanks everyone for your advice. I didn't realise the default brake bias wasn't optimal.

 

[rockerbauer]

Real cars don't have 100% braking. What you're seeing is brake pressure calibrated to a certain force for 100% - so anything higher isn't visible.

Not sure of what you mean here, but seems you are talking about lowering braking pressure at setup, which would make brake distance higher and therefore not desirable.
There are lots of 2024 SPA onboards, hypercars, GT3, almost all of them do not trail brake and can keep 100% (of whatever would be the optimum brake pressure) as much as the car can get close to 100km/h.
For people with load cell brakes it should be very comfortable braking without regular lock-ups.

 

[Aysedasi]

I run my brakes now at around 95% and now lock up pretty rarely. I'm doing as suggested, moving the bias towards the rear as the session/race progresses. I'm feeling much more comfortable with it now, although I'm struggling to get within half a second of the times that I was doing previously. But I'm staying on the track, I seem to be able to race much better and I'm getting better results, so it's been a win-win so far for me.

 

[rockerbauer]

I run my brakes now at around 95% and now lock up pretty rarely. I'm doing as suggested, moving the bias towards the rear as the session/race progresses. I'm feeling much more comfortable with it now, although I'm struggling to get within half a second of the times that I was doing previously. But I'm staying on the track, I seem to be able to race much better and I'm getting better results, so it's been a win-win so far for me.

Ok, but think about qualy sessions, lighter cars, fresh tires, send it all, you aren't supposed to lock your wheels in this pushing mode as well. Plus the front tires degradation shouldn't be higher than the rear ones throughout the race.

 

[Lazza]

Not sure of what you mean here, but seems you are talking about lowering braking pressure at setup, which would make brake distance higher and therefore not desirable.
There are lots of 2024 SPA onboards, hypercars, GT3, almost all of them do not trail brake and can keep 100% (of whatever would be the optimum brake pressure) as much as the car can get close to 100km/h.
For people with load cell brakes it should be very comfortable braking without regular lock-ups.

Ok, let's assume for a moment we're excluding brake by wire.

You push the brake pedal really really hard, with x kg on the pedal, and that gives y kPa in the brake lines. What if you push a bit harder? More pressure. Harder again? More pressure.

If you're displaying "brake pedal" somewhere, you have to measure it in some way, likely force at the pedal or system pressure (less likely: pedal movement, hello Asetek), and for display purposes you have to choose what force/pressure corresponds to 100%. If you set that maximum too high you will capture every detail of the brake application, but it will never register 100%.

What you're more likely to do is set it at a level where pressing the brake really hard (only) shows 100%, so it doesn't look like you're on a Sunday drive braking at 80% as your tyres wear or the track gets hot and greasy. But that means you actually hit more than 100% a lot of the time, which doesn't get shown. The 100% level isn't any sort of physical maximum, it's just an arbitrary figure chosen for the best desired display result.


Brake by wire shouldn't be any different in practice (even if regulations allow it), because the last thing you want is deadzone.

The tl;dr is: real life doesn't work like games.

 

[GoooAlex]

Yeah, I've heard that real life is analogical.

 

[robevery1971]

After a few hours so far I am finding the braking very tricky, a lot of locking and a very odd feel, it makes trail braking very difficult.

But I come from 1000 odd hours in Acc.

You also have to understand that game is about one class really, so you can design and focus the physics that way, this game will inevitably be about primarily Hypercars.

Trying to make both work using the same physics engine will inevitably lead to issues with GT cars

 

[GoooAlex]

These cars don't have ABS, so braking is more complicated even in real life than ACC's GT3s.
Which in reality even braking on ACC is not at all simple if you want to be competitive. Let's say that at the beginning it is easier to "walk" around the track. On ACC you have acquired skills that you will now have to acquire from scratch on the new simulator.

 

[FrenchKiss]

I don't find anything weird in the physics of LMU braking, on the contrary, it's quite successful for me. It is not surprising that the braking is not the same from one corner to the next, the grip, the unevenness of the track, the mass transfers mean that each braking at the limit is a challenge and that is there. 'interest. ACC eliminates this thanks to the ABS which adapts (bridles) the braking and therefore on ACC it is the management of the ABS which takes precedence over the precision of the foot, you brake fully and the ABS manages it. It's more of an engineer's job, whereas without ABS, it's a driver's job. The fact that there are several types of cars does not seem to me to be a problem for their game engine either, it is just up to the player to adapt their settings according to the vehicle.

 

[FrenchKiss]

Ce qui en réalité même freiner sur ACC n'est pas du tout simple si l'on veut être performant. Disons qu'au début il est plus facile de « marcher » sur la piste.

My solution for adjusting a car with ABS is to deactivate it to adjust the braking because otherwise you don't understand which wheel loses grip first and triggers the ABS. Once the braking is effective without ABS I reactivate it.

 

[robevery1971]

I am fully aware of having to change skills, this is no problem, I am for now adjusting the pedal pressure to help, but I cannot trail brake anywhere near as much in GT cars, most likely a bias thing, if you try and trail, the arse end comes round, if you do this in Acc you invariably get a ton of push as the default setups are very safe

 

[FrenchKiss]

Yes, which is why karting is very educational. If you have 2 hours to waste, do a few karting laps IRL (or on KartKraft which is sensational) and you will (re)discover what braking by feeling is, which is used to slow down the car but also to place the forward into the bend, it's so exhilarating

 

[robevery1971]

lol, parlezvous Anglais, desole?

 

[FrenchKiss]

sorry I have a translator who transforms web pages into French so I can't see if my text is in English or not. I modified them.
Sorry

 

[robevery1971]

No need to apologise

What this shows is clearly that the site needs a section en Francis in my opinion. thankyou for making the effort to reply!

 

[FrenchKiss]

no, not at all, it's a misunderstanding, I translated into English but the software retranslated into French without me being able to see it.
I feel good here, no worries...

 

[rockerbauer]

Ok, let's assume for a moment we're excluding brake by wire.

You push the brake pedal really really hard, with x kg on the pedal, and that gives y kPa in the brake lines. What if you push a bit harder? More pressure. Harder again? More pressure.

If you're displaying "brake pedal" somewhere, you have to measure it in some way, likely force at the pedal or system pressure (less likely: pedal movement, hello Asetek), and for display purposes you have to choose what force/pressure corresponds to 100%. If you set that maximum too high you will capture every detail of the brake application, but it will never register 100%.

What you're more likely to do is set it at a level where pressing the brake really hard (only) shows 100%, so it doesn't look like you're on a Sunday drive braking at 80% as your tyres wear or the track gets hot and greasy. But that means you actually hit more than 100% a lot of the time, which doesn't get shown. The 100% level isn't any sort of physical maximum, it's just an arbitrary figure chosen for the best desired display result.


Brake by wire shouldn't be any different in practice (even if regulations allow it), because the last thing you want is deadzone.

The tl;dr is: real life doesn't work like games.

Yeah, you have a point here, but what should be the optimum brake pressure since we know IRL drivers have some personal and natural preferences?

Plus they use inertia to help in the high braking zones, like at the end of big straits, which means, they use almost the same force in that braking point as any other parts, for instance, starting braking at 350km/h the inertia will help a lot with maximum pressure, and starting braking at 200 inertia is lower although the driver's leg pressure is basic the same.

For that I think the graphics can provide a good point of start and the game should provide a more optimized brake pressure since we don't have inertia to help and we need a more linear muscle memory to feel good driving the cars, especially at long runs.

 

[GoooAlex]

I am fully aware of having to change skills, this is no problem, I am for now adjusting the pedal pressure to help, but I cannot trail brake anywhere near as much in GT cars, most likely a bias thing, if you try and trail, the arse end comes round, if you do this in Acc you invariably get a ton of push as the default setups are very safe

What I understood. Which could be wrong, do your own experiments. In this sim, the variation in grip due to tire wear seems important. With each lap your braking changes, as does the Trail breaking you have to do to enter the corner. So the problem is always understeer. The cars have an understeer setting. The Ferrari GTE, for example, is very stiff at the front and soft at the rear. So with new tires you go into corners well. As you turn, your tires, especially the outside front, will wear, and the car will slow down less. This will lead you to press the brake slightly more to compensate. But you will also go wide due to the car's understeer and front tire wear. So you will turn the steering wheel a little more with each turn. Until, 10 or 15 minutes later, you will force it too much on the apex and you will lose it behind. Or you'll come to the apex with the car fully pointed at the front, and lose it as soon as you try to accelerate.
Now, if my setup is Fixed, the only thing I could do is balance the brake at the rear, and continue to move it backwards, as soon as the difference between front and rear reaches 3-4%. 5% difference is already difficult to ride for me, especially in the race.
If, however, I have a variable setup, one click less on the front bar allows me to make more use of the suspension and a little less of the tire. Slightly inflating the front support tire helped to contain the temperature and reduce consumption, as did opening the brake ducts.
And in any case keep in mind that as time passes you have to lengthen your braking. Other sims seem to compensate with fuel consumption or something like that, so more or less the braking points are always the same, this one seems more demanding in terms of tire management and braking distances.

 

[Lazza]

Yeah, you have a point here, but what should be the optimum brake pressure since we know IRL drivers have some personal and natural preferences?

Plus they use inertia to help in the high braking zones, like at the end of big straits, which means, they use almost the same force in that braking point as any other parts, for instance, starting braking at 350km/h the inertia will help a lot with maximum pressure, and starting braking at 200 inertia is lower although the driver's leg pressure is basic the same.

For that I think the graphics can provide a good point of start and the game should provide a more optimized brake pressure since we don't have inertia to help and we need a more linear muscle memory to feel good driving the cars, especially at long runs.

My main point was that people see the (relatively rare) dynamic brake input graphics from real life and think the drivers are actually "full" braking for the first ~half of the braking phase, when it's really just that we aren't seeing what they're doing. (in series like F1 you don't see any detail at all, it's just on-off)

I agree that it would be easier to apply high forces to the brake pedal when you are in a decelerating car as opposed to sitting in your sim rig / office chair, but I think you might be overestimating how beneficial the varying forces would be for managing the brake pressure. If there is a feel advantage it might be from the g forces that you miss entirely in a sim.

Anyway, even if the long G force translates directly into, let's say, the forward force of your hips (and it won't, because seat and harness) your leg still has to take that force, and you will feel the difference.

Basically, missing real forces aside, I don't think real drivers have any advantage over simracers.

You also have to understand that game is about one class really, so you can design and focus the physics that way, this game will inevitably be about primarily Hypercars.

Trying to make both work using the same physics engine will inevitably lead to issues with GT cars

A physics engine can impose a certain flavour to some things, but in this case I don't think it's an issue. Even if it hasn't changed from rF2 the physics related to braking can do a fine job in basically any car. There's no inevitability at all to favouring one type of car over another.

 

[rockerbauer]

Basically, missing real forces aside, I don't think real drivers have any advantage over simracers.

They have, it has been said already, Daniel Morad said he uses less pressure in the Sim than he used to in real cars because of g forces. It is something natural g force will oblige you to use more force in the leg.

Who would guess...