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Neb911
11-03-2018, 04:41
So I am watching these GT3 race videos with telemetry shown and I notice that drivers hardly do any brake modulation at all?

It basically looks like what I'm doing with ABS on, just stomping on it until safe speed reached for the corner. I'm playing with controller so I'm not the most sim hardcore driver out there but these are real life videos and I expected them to be more cautious on the brakes.

How come they don't lock up the tires? Is it because GT3 have ABS too or am I missing something there? Brake pressure perfectly adjusted maybe?

Is it possible to avoid lock ups with brake pressure setting done properly or is it still matter of "feeling it" on the track?

hkraft300
11-03-2018, 05:01
Is it possible to avoid lock ups with brake pressure setting done properly?

Yes.
If you reduce the brake pressure enough, the brake force is reduced and will not overcome tire grip, therefore no lock up.

I'm sure if the real cars still really stand non their brakes they'll lock up.

Neb911
11-03-2018, 05:06
Yes.
If you reduce the brake pressure enough, the brake force is reduced and will not overcome tire grip, therefore no lock up.

I'm sure if the real cars still really stand non their brakes they'll lock up.

I literally saw Ferrari having full red bar on the brake telemetry until last 20m where he backs up to 80-90% and that's it. Just thought there would be more up and down in the brake bar...but nothing.

John Hargreaves
11-03-2018, 05:28
I thought the real cars used ABS? It's only simracers that insist on running without as they are all hardcore. Could well be wrong though.

Blaulicht
11-03-2018, 05:29
All series featuring GT3 cars coming to my mind right now have ABS and TC allowed, which means everybody uses them.

The common assumption that driving without aids is faster is not true btw, so drive with whatever is allowed

Neb911
11-03-2018, 06:12
I thought the real cars used ABS? It's only simracers that insist on running without as they are all hardcore. Could well be wrong though.

I guess this is peer pressure of feeling not being hardcore by simracers standards :)

Anyways I thought real drivers not use it that much, but it does makes sense, why not make it easier...more time to concentrate on racing.

hkraft300
11-03-2018, 07:52
I literally saw Ferrari having full red bar on the brake telemetry until last 20m where he backs up to 80-90% and that's it. Just thought there would be more up and down in the brake bar...but nothing.

Maybe that's all the necessary threshold braking.
They have lots of grip.
It's not in their best interest to constantly rely on abs, because tire wear.

John Hargreaves
11-03-2018, 08:07
I guess this is peer pressure of feeling not being hardcore by simracers standards :)

Anyways I thought real drivers not use it that much, but it does makes sense, why not make it easier...more time to concentrate on racing.

I guess a pro team/driver is only concerned with whichever is faster. It's hard to imagine a race team adding ABS systems if the car is faster without it.

Neb911
11-03-2018, 10:01
I guess a pro team/driver is only concerned with whichever is faster. It's hard to imagine a race team adding ABS systems if the car is faster without it.

Yeah, they don't need to prove they have the balls to race...ABS or not they do it for real, not in their PJ's in comfort of a "pro" home racing setup.

hkraft300
11-03-2018, 11:20
I guess a pro team/driver is only concerned with whichever is faster. It's hard to imagine a race team adding ABS systems if the car is faster without it.

Rules mandate it.
Threshold braking is still better than abs.

Jussi Karjalainen
11-03-2018, 11:45
How come they don't lock up the tires? Is it because GT3 have ABS too or am I missing something there? Brake pressure perfectly adjusted maybe?GT3 cars in real life run ABS and Traction Control. Also I've often noticed that the onscreen telemetry in most videos, Formula One being a good example, only shows the throttle as an analog input, the brakes are merely an on/off trigger in the visualization. So just because the on-screen telemetry doesn't show any variation doesn't mean they're not feathering the brakes at all.

Showcasing the brakes like that is more difficult anyway than it is with throttle, since brakes in real life function on pressure, not pedal travel. You need to tie the visualization to a pressure meter, and then calibrate that properly, whereas with the throttle it's a simple position measurement.

If you did see one where they actually do back up, then that's great, I'd like to see more of that happen, it'd make hunting for data easier. =)

Jussi Karjalainen
11-03-2018, 11:47
I guess a pro team/driver is only concerned with whichever is faster. It's hard to imagine a race team adding ABS systems if the car is faster without it.Modern racing ABS systems are incredibly good, and better than most privateer racers I'd say. Our system is a bit more basic than that, and you'll definitely be quicker if you manage to stay just a hair below the activation threshold at all times.

That said the biggest advantage of ABS is accident avoidance. Locking tyres up can be a pretty bad time, so it's best to avoid that as much as possible. Even if the drivers aim to not trigger the ABS it's good to have it there as a backup if things go wrong.

Blaulicht
11-03-2018, 11:50
Threshold braking is still better than abs.

A modern ABS system will always outperform any driver especially in wet conditions

hkraft300
11-03-2018, 12:31
A modern ABS system will always outperform any driver especially in wet conditions

Actually, by its very mechanism of grip-slip-grip-repeat, a driver staying at the edge of the braking grip limit will still outperform ABS. Because grip friction > slip friction.

ABS loses because of the distance traveled with the tires locked.

Jussi Karjalainen
11-03-2018, 13:31
Because grip friction > slip friction.Well, tyres do their best work with some amount of slip (actually without any slip there isn't really any grip, look at any slipcurve for an example), usually in traction/braking it's about 15-20%, so that's what the target really is. Modern road going ABS systems can't manage to hold it there properly, but racing ABS systems get really dang close.

blinkngone
11-03-2018, 13:48
You can find different responses to this. I found some that said on their racing team the ABS was more of a fail safe to save tires in case of driver error but under normal conditions the driver was better than ABS. I found one example with DTM in the rain at Spa when the ABS failed the driver/car was 3 seconds a lap slower. In this game I am probably better with ABS when allowed because I am not a good driver. I will be out braked by an experienced/good driver in either case. I suspect that I am in the majority needing ABS when allowed.

hkraft300
11-03-2018, 13:49
...usually in traction/braking it's about 15-20%, so that's what the target really is. Modern road going ABS systems can't manage to hold it there properly, but racing ABS systems get really dang close.

You know what I meant.
I'm surprised optimal braking slip is that high. I thought it'd be lower, or closer to the lateral slip %.

RomKnight
11-03-2018, 15:32
Modern racing ABS systems are incredibly good, and better than most privateer racers I'd say. Our system is a bit more basic than that, and you'll definitely be quicker if you manage to stay just a hair below the activation threshold at all times.

That said the biggest advantage of ABS is accident avoidance. Locking tyres up can be a pretty bad time, so it's best to avoid that as much as possible. Even if the drivers aim to not trigger the ABS it's good to have it there as a backup if things go wrong.

Totally confirm this, which is why I recommend - if possible - to upgrade to load cell brake mod or pedals. Makes it so much easier/intuitive to manage that even load cell newcomers can feel it. It just works.

Who was that RL driver that commented that the GT3 cars were a pain under braking because of the ABS gave them such an advantage wrt to GTE cars? I recall that but not the video nor driver :(

And ofc I also remember an ADAC GT Masters race last or a couple of years ago race in the rain where a driver told that they just set the ABS and stomp on the brakes at the right time that the car will slow just enough to T1. This was at Nurburgring GP.

Talking to RL drivers (mentioned this before) since FIA GT1/3 days at least, the answer is usually: practice no ABS (and or TC) to get a proper feel for the car to set it up and same for quali as it's usually faster without ABS but some laps are done with as it can be faster that way. Race, set it to lowest manageable by the driver to save tyres mainly.

Rain is a different issue and it's just better to run ABS (and or TC) to the lowest possible to not let the car get slower.

Things evolved quite a bit wrt to electronics and it's mainly an advantage, period. It's quite tricky and complicated and it's almost like suspension settings. There are no adjustments, only one or 3 usually and on top of that you can still have fast and slow for add ease of use :P :D

Personally, I can live without TC (in rain if available, I have it on low) but ABS in-game is always on to low when available. It just works better but again, find that activating threshold as mentioned and it'll improve your driving quite a bit.

Jussi Karjalainen
11-03-2018, 16:24
You know what I meant.
I'm surprised optimal braking slip is that high. I thought it'd be lower, or closer to the lateral slip %.Yes, I did, but also wanted to expand a bit. =)

The point there really is how well the braking system can detect slip and modulate the brakes. Modern racing systems can run at over 100 Hz, i.e. calculate the slip and readjust the brake pressure 100 times per second (compared to some older road systems that were more like 5-10 Hz), and even if they perhaps didn't quite effectively reach that in practice due to the way hydraulics work they can still control the exact amount of slip remarkably well. That's mostly something that's been happening in the last few years though, it's a pretty new phenomenon.

davekojo
12-03-2018, 00:39
The issue with the ABS argument is that it relies on theoreticals. Real life is different. Race tuned (modern) ABS over the course of a race will allow the driver to finish the race faster plain and simple. Straight line/Threshold braking is not the only consideration when it comes to driving on a track. ABS reduces tire wear, allows drivers to "cheat" when trail braking, removes big human inconsistencies when it comes to braking.

You should probably follow the rule of if its banned in F1 it makes the car faster IRL. ABS, Launch Control, Traction Control, Active Suspension.

The last Pro I saw who comment on ABS being faster for braking was SMS Development Driver (I think he's some kind of IMSA pro or something :p) Tommy Milner. He talked about how GT3 lap times were faster than they otherwise would be because of what ABS allowed them to do in the braking zones.

ermo
12-03-2018, 11:13
Yes, I did, but also wanted to expand a bit. =)

The point there really is how well the braking system can detect slip and modulate the brakes. Modern racing systems can run at over 100 Hz, i.e. calculate the slip and readjust the brake pressure 100 times per second (compared to some older road systems that were more like 5-10 Hz), and even if they perhaps didn't quite effectively reach that in practice due to the way hydraulics work they can still control the exact amount of slip remarkably well. That's mostly something that's been happening in the last few years though, it's a pretty new phenomenon.

If you have a source/spec sheet for that, I'd be *very* interested in seeing it, given that e.g. Bosch states that its racing ABS systems are essentially equivalent to its road systems, just with different calibration and more adjustment controls exposed to the user (=engineer) for programming?

Not saying I don't believe you btw -- just curious where you found it. :)

Casey Ringley
12-03-2018, 19:49
I thought the real cars used ABS? It's only simracers that insist on running without as they are all hardcore. Could well be wrong though.

Correct.

We had a really neat consultation session at CXC early in development of the game that demonstrated this. In the morning, a factory Bentley GT3 driver came in to test their car and was just mashing the brake pedal in every corner; letting ABS do all the work of modulating pressure. Later that day we had Tommy come in to try the C7.R. Set up like the real thing with TC only, and without any prompting from us other than 'drive it like you would the real thing and see where it falls down', you could instantly see how much more gentle he was with the brake pedal to avoid lock-ups. 'Oh yeah, the GT3 cars kill us in braking zones because of the ABS.'

hkraft300
13-03-2018, 00:27
Guess I'll eat my words then.
It only applies in Ye olde times or road cars.

Jussi Karjalainen
13-03-2018, 01:01
Guess I'll eat my words then.
It only applies in Ye olde times or road cars.Don't feel bad, it used to be true not too many years ago. The systems these days have just gotten superlatively good relatively recently.

Neb911
13-03-2018, 07:12
This is one of the videos, Ferrari, literally the first seconds of the video braking in to La Source at SPA...stomp it, back off a bit near the end and repeat on the next corner. :)

For some reason video keeps starting later on, weird.


https://youtu.be/hxz91nhtsEE

bazzalaar
13-03-2018, 12:37
I've got experience in a GT4 (Nissan 350z) My housemate has raced GT4 and GT3 both have TC and ABS.
They raced a 488 at Monza last year. Everyone runs with the aids, No one is a hero and switches them off. You want to be braking to the point just before the ABS kicks in, you'd then "bleed" off the brake upon corner entry, which is all about stability and settling the weight before you turn. Useful when going from a high speed to a low speed corner. (e.g. T1 at Monza) So it's not quite a case of mash the pedal and let the car do the work. The system is good for tweaking during a long stint. if you were to spend 3 hours on the same set of tyres, you can adjust TC and ABS to help with the traction loss through tyre degradation.

Ofnir4
13-03-2018, 12:51
As ABS is standard, not using 100% braking power is just giving yourself a handicap unless you are in a specific situation that doesn't suit that need. (like let's say at VIR where corners lead into other tighter corners)
Where it gets more interesting is how they get off the brakes, different drivers, different techniques, different results.

GT3 is popular because it's easy to drive and be relatively fast, in sim racing as well. But some people like to make things more difficult that they really are...

Mahjik
13-03-2018, 12:53
This is one of the videos, Ferrari, literally the first seconds of the video braking in to La Source at SPA...stomp it, back off a bit near the end and repeat on the next corner. :)

That's pretty much textbook braking for when you are on a race track. Braking on a race track is the opposite of how we brake on public streets. On public streets, you slowly start to brake, and then only increase braking pressure if you need to stop sooner. In racing, it's the opposite. You brake hard initially then back off until you have your desired corner entry speed. When I am instructing, getting a student to use the brakes properly on a track is the first hurdle that is the hardest for most drivers that have been driving public roads for a long time.

Second hurdle is turning in at the right time. So hard for new drivers to learn that sometimes they have to wait a bit to turn in rather than what their mind tells them (see a turn, make a turn).

ermo
13-03-2018, 14:40
That's pretty much textbook braking for when you are on a race track. Braking on a race track is the opposite of how we brake on public streets. On public streets, you slowly start to brake, and then only increase braking pressure if you need to stop sooner. In racing, it's the opposite. You brake hard initially then back off until you have your desired corner entry speed. When I am instructing, getting a student to use the brakes properly on a track is the first hurdle that is the hardest for most drivers that have been driving public roads for a long time.

Second hurdle is turning in at the right time. So hard for new drivers to learn that sometimes they have to wait a bit to turn in rather than what their mind tells them (see a turn, make a turn).

Don't know if it's true, but apparently Fernando Alonso didn't have a driver's license during the period where he won his 2 WDCs because, (as Jack Baruth of Road & Track put it (https://www.roadandtrack.com/motorsports/a18663299/how-your-commute-is-teaching-you-to-do-the-exact-wrong-thing-on-track/)): "Any time you're driving, you're training yourself to drive".

So Fernando caught a cab if he needed to go anywhere on public roads just to avoid practicing "wrong braking".

bmanic
13-03-2018, 17:57
That is so Alsonso of him.. :)

Love that guy for these kinds of things! He is such a perfectionist.

g.stew
13-03-2018, 18:50
That is so Alsonso of him.. :)

Love that guy for these kinds of things! He is such a perfectionist.

Lol...This has me thinking of what other drivers would say..

Interviewer: Kimi, do you have any special tricks or techniques you use for braking?

Kimi Räikkönen: Bwoah, I press the brake pedal with my foot when I want the car to slow down.

Raklodder
13-03-2018, 21:22
Let's say I was a real GT3 driver, would I be allowed to drive without driving aids or is that mandatory?

I'm just curious to know whether I should change my in game settings or not to keep it as real as possible.

hkraft300
13-03-2018, 21:29
Let's say I was a real GT3 driver, would I be allowed to drive without driving aids or is that mandatory?

I'm just curious to know whether I should change my in game settings or not to keep it as real as possible.

There is a realistic setting that will turn the aids on as per the real car. Then in car tuning you can set up the sensitivity of the abs and tc to your liking.

HLR Toffo
13-03-2018, 21:36
Its all relative to speed,grip and downforce. Faster your going the heavier you can brake but you must bleed off the slower your going or you'll lock up or upset the car.

Only cars that benefit the most from abs in this game imo are street and gt3s.

Formulas and lmp use ceramics and dont need abs they can stop really quickly and are very easy to modulate without lockups. Probably gaining braking performance without interference of abs. Due to the fact your at 100% quickly and heavily where a steel brake car would lockup if you broke the same.

Raklodder
13-03-2018, 21:47
There is a realistic setting that will turn the aids on as per the real car. Then in car tuning you can set up the sensitivity of the abs and tc to your liking.
Thank you for making it clear to me, I will try it out first thing tomorrow night, but you touched on something else that I would like to clear up, that is, tuning your driving aids.

I'm just so afraid of making it to simple (or "arcadeish") and just float around on the track with full grip, but at the same time, I'm tired of having to fight with my breaks in the rain.

hkraft300
13-03-2018, 22:27
I'm just so afraid of making it to simple (or "arcadeish") and just float around on the track with full grip, but at the same time, I'm tired of having to fight with my breaks in the rain.

You can’t. Assists won’t beat the physics. Tire grip is still limited.
Just remember 1% TC actually means TC will only allow 1% slip, so it’s the strongest setting. 100% TC basically turns it off. ABS I believe is opposite. So you can adjust them to only intervene when you completely overdo it.

Jussi Karjalainen
14-03-2018, 01:06
Let's say I was a real GT3 driver, would I be allowed to drive without driving aids or is that mandatory?

I'm just curious to know whether I should change my in game settings or not to keep it as real as possible.I am not 100% sure on the exact regulations (and they might differ from series to series anyway, GT3 isn't like F1, there are dozens of series running GT3 cars, all with the possibility of rule differences), but the team leader would probably tell you to keep them on to make sure you don't ruin tyres by accident... =)


You can’t. Assists won’t beat the physics. Tire grip is still limited.
Just remember 1% TC actually means TC will only allow 1% slip, so it’s the strongest setting. 100% TC basically turns it off. ABS I believe is opposite. So you can adjust them to only intervene when you completely overdo it.Yup, TC is direct slip percentage, and IIRC with TC set to Low the system doubles the allowed slip amount, so if you set the allowed slip to 10%, you get 10% slip with TC High and 20% slip with TC Low.

ABS works a bit differently, you're not directly adjusting min and max slip allowed but also how quickly the system wants to react, which is why it's an "ABS strength" slider (so basically TC adjusts one thing, ABS adjusts several things, hence the different approaches).

I would heartily recommend trying to set your brakes (pressure and bias) up so that you don't trigger ABS too often. We didn't want to make the ABS too perfect for the game, so you can definitely lose performance if it's triggering all the time. If it gets triggered a couple of times when braking hard from a high speed its' OK, but if it's constantly triggering whenever you hit the brakes your braking distances will be significantly longer than they have to be.

cpcdem
14-03-2018, 03:50
Yup, TC is direct slip percentage, and IIRC with TC set to Low the system doubles the allowed slip amount, so if you set the allowed slip to 10%, you get 10% slip with TC High and 20% slip with TC Low.


Could you please confirm, because an other dev guy had said that it's more like HIGH TC means the system completely cuts off engine power when max slip is reached, while LOW cuts engine to 50% or so. I thought I had bookmarked this post, but can't find it..
Also the way it works in practice makes me believe that it indeed works that way, although it could be placebo, you know, people believe what they heard first :)

Jussi Karjalainen
14-03-2018, 08:07
I'll get a proper confirmation, but that's the way it was explained to me when I last asked. =)

Shepard2603
14-03-2018, 08:09
I'll get a proper confirmation, but that's the way it was explained to me when I last asked. =)
http://forum.projectcarsgame.com/showthread.php?57967-New-behavior-of-traction-control-toggle&p=1434047&viewfull=1#post1434047

Matt York
15-03-2018, 14:42
http://forum.projectcarsgame.com/showthread.php?57967-New-behavior-of-traction-control-toggle&p=1434047&viewfull=1#post1434047


Could you please confirm, because an other dev guy had said that it's more like HIGH TC means the system completely cuts off engine power when max slip is reached, while LOW cuts engine to 50% or so. I thought I had bookmarked this post, but can't find it..
Also the way it works in practice makes me believe that it indeed works that way, although it could be placebo, you know, people believe what they heard first :)

The values in that post of mine you linked were to be used as an example, to help explain what the system is doing. As I said in that post, they weren't/aren't the actual values that were being used for the TC system.

Zaskarspants
15-03-2018, 15:01
Excellent thread. Thanks everyone.

I race with all driver aids off.
When I started with pcars I tried the gt3 with aids on but I found them too strong and I never experimented. Seems I was hasty.

Having read everything here I can see I have failed to appreciate the nuances of the systems and the benefits when used sensibly. This may also explain why gt3 is the formula where I use the lower end of my usual difficulty scale.

cpcdem
15-03-2018, 17:18
The values in that post of mine you linked were to be used as an example, to help explain what the system is doing. As I said in that post, they weren't/aren't the actual values that were being used for the TC system.

I know, that's why I said "50% or so" :)
Anyway, the point was that if I understand correctly, the slip amount at which point TC kicks in is always the same (as defined in the setup), while LOW/HIGH affects how much intrusive the system is at that same point.

AbeWoz
15-03-2018, 18:52
Anyway, the point was that if I understand correctly, the slip amount at which point TC kicks in is always the same (as defined in the setup), while LOW/HIGH affects how much intrusive the system is at that same point.

That's the way I understand it as well, same with ABS

blinkngone
17-03-2018, 19:06
Probaly not much to do with PCars2 but they are racing at Sebring today and the concerns of the teams in GTD are the excessive brake wear due to the overheating/wear of the rotors caused by the ABS. They are trying to figure out when to change the rotors or ask the drivers to manage the ABS so the rotors are damaged the least.