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Rockefelluh
23-10-2015, 18:41
Driving question. I use real life assists. Does mashing the brake on cars with ABS produce the shortest stopping distance? I imagine there is a sweet spot somewhere between 0 and 100 just like cars with no ABS?

Sir Digby Chicken Caesar
23-10-2015, 19:16
Driving question. I use real life assists. Does mashing the brake on cars with ABS produce the shortest stopping distance? I imagine there is a sweet spot somewhere between 0 and 100 just like cars with no ABS?

I'm not 100% sure but I think stopping distance is slightly shorter if you ride the threshold of ABS kicking in. That said, ABS is so reliable that I don't know if it's worth it to try braking...properly. Though it might be if you have a really good brake pedal. I don't like ABS in real life (I'm sure you've heard the phrase "anti-stop brakes"), but with the T300 pedal or a controller, it's nice.

Tomcul
23-10-2015, 20:31
Ya in my opinion it's better to try and brake properly there is a sweet spot..
Or you could map abs to a button and turn it off..

Rockefelluh
23-10-2015, 20:38
Ya in my opinion it's better to try and brake properly there is a sweet spot..
Or you could map abs to a button and turn it off..

I just find it difficult to find the abs point when braking. I don't feel it quite that much through the wheel, unless I am missing something. It's nice having the safety net of abs, but I also find I cant brake consistently because I can't feel the abs.

DECATUR PLAYA
23-10-2015, 20:45
Driving question. I use real life assists. Does mashing the brake on cars with ABS produce the shortest stopping distance? I imagine there is a sweet spot somewhere between 0 and 100 just like cars with no ABS?

I'm no expert. But.....

ABS only stops the wheels from locking up so depending on your braking style it may or may not increase your braking distance.

Real stopping power is a combination of 4 things.

Brake pressure
Brake temperatures.
Brake bias (front/rear)
Weight distribution (affects brake bias)

You will notice on your out lap that brakes don't work very well until they heat up. If you run the brakes above 1400 degrees the brakes can become ineffective especially in very heavy cars. Some cars can get away high brake temps some can't.

Most of my tuning is with ABS on.

DECATUR PLAYA
23-10-2015, 20:48
I just find it difficult to find the abs point when braking. I don't feel it quite that much through the wheel, unless I am missing something. It's nice having the safety net of abs, but I also find I cant brake consistently because I can't feel the abs.

Increase your pressure. If that doesn't work open your brake duct more.

madmax2069
23-10-2015, 20:50
If you mash the brakes in a ABS equipped car you will have a shorter stopping distance vs a non ABS car with its brakes locked, but if you can avoid brake lock in the non ABS you'll have a shorter stopping distance then the ABS car if you mash the brakes and ABS kicking in. They'll be about the same as each other if you avoid the ABS kicking in on the ABS equipped car and avoid brake lock on the non ABS equipped car. This is going by identical cars where the only difference is one has ABS vs one with no ABS.

ABS is only to keep from locking up the brakes so you can maintain control of the car (maintain steering and stopping in a straight line, vs a non ABS when brakes lock you'll have no steering and car usually dont maintain in a straight line).

Like the above post says, you have to ride the line just before ABS kicking in to get the maximum braking power, and the shortest stopping distance.

Rockefelluh
23-10-2015, 21:31
Yeah, makes sense. You want the tires to still roll and have static friction which is more grip and than kintectic (skidding).


Increase your pressure. If that doesn't work open your brake duct more.

Like I said, I just have issues finding the point of abs turning on. How would increasing brake pressure remedy this?

Brake temp isn't the problem. I keep an eye on brake temp and adjust ducts accordingly.

miagi
23-10-2015, 23:50
Driving question. I use real life assists. Does mashing the brake on cars with ABS produce the shortest stopping distance? I imagine there is a sweet spot somewhere between 0 and 100 just like cars with no ABS?
That one is a bit complicated. It depends on what and how the ABS is used. With a well set up brake system, good drivers can brake better without ABS. On the other hand, the ABS system does a good job keeping the wheels close to its limit. It even learns. The actual advantage is that the ABS system can get all 4 tyres to the limit. Without ABS that is only possible with a well set up brake and only for a certain friction coefficient!

In real life, GT3 cars run very high brake pressure and relay on the ABS system to get the best out of the tyre in a straight line. However that doesn't mean you can't spin on braking with ABS. If you put too much lateral force while braking the tyre can be pushed beyond there limit and the car spins off.

To answer your question, in a straight line, with ABS, smash the brake pedal, the ABS will do the rest. However, once you start turning the wheel, things look different. You should know what you do from that point on. While trail braking I usually apply only little force and go even lower up to the apex. If I want the car to drift into the corner, I leave a certain brake force constant, that way the car starts turning more and more until it gets sideways at some point. That is the latest point you should be on the brake, because then countersteer and working the throttle should be needed to stabilize the car.

PS: A tyre gets the highest force output at about 50% static and 50% sliding friction.

PPS: Just to make this clear, ABS does not prevent the tyres from locking. That happens as a side effect(The ABS system can't make a difference between all 4 tyres locked while doing 160 kph and standing still on the lights, it's not how it works. Also if the ABS would wait for a tyre to lock to reduce brake pressure, it would take much much to long and the tyres would be square in the end.), what ABS really does resp. trys to do, is hold the tyre at its longitudinal force maximum on the stable side. It calculates how much the rotation speed and rotation acceleration of the wheel changes and looks for the highest corresponding coefficent. It trys to guess it and it learns, while it recalculates the rotation speed and rotation acceleration of the wheel all the time.

Rockefelluh
24-10-2015, 01:46
Epic response Miagi, thank you. I always thought ABS worked by detecting lock up. So I have some reading to do.

Also, you said about 50:50 static/slide is highest tire force output. But static friction is higher than sliding so why would this be the case? A link to an article would be fine in place of long winded answer.

DECATUR PLAYA
24-10-2015, 23:40
Epic response Miagi, thank you. I always thought ABS worked by detecting lock up. So I have some reading to do.

Also, you said about 50:50 static/slide is highest tire force output. But static friction is higher than sliding so why would this be the case? A link to an article would be fine in place of long winded answer.

I read your opening post again and realised what you was asking for. Like a few others above stated yes just mash the brakes. I also understand now that the feeling in your wheel is different from my controller. You can push the car much deeper in the turn and brake harder with ABS.

DECATUR PLAYA
24-10-2015, 23:46
Epic response Miagi, thank you. I always thought ABS worked by detecting lock up. So I have some reading to do.

Also, you said about 50:50 static/slide is highest tire force output. But static friction is higher than sliding so why would this be the case? A link to an article would be fine in place of long winded answer.

I read your opening post again and realised what you was asking for. Like a few others above stated yes just mash the brakes. I also understand now that the feeling in your wheel is different from my controller. You can push the car much deeper in the turn and brake harder with ABS.