Originally Posted by jayzbird

In retrospect I wish I had spent more time learning the basics in a less capable car than a 911 turbo.

Originally Posted by HenryPcar

You nailed it !

Originally Posted by fleadh

Over the last few years I've driven a lot of race cars with (motorsport) ABS and the cars are always fastest when staying out of the ABS if it activates on more than wheel at the same time and you can feel it in the pedal:

Straight line braking over bumps? You're going to have a hard time making the corner, if you're on the limit.
Straight line braking w/o bumps? It's not as bad as above, but it generates so much heat in the system you generally don't want to drive this way. Also, the more you rely on the ABS the harder it is to come off the brake pedal and have it transfer the weight as you'd expect. Still will slightly increase the length of the braking zone.
Heavy trail braking into a bumpy corner? Very inconsistent and you won't slow the car down much. Point above about coming off the brake pedal multiplied by 8123394x. Avoid when possible.
Heavy trail braking into a smooth corner? Over loads the front tires and car simply won't turn.

Once you activate ABS bleeding off the pedal doesn't necessarily release a proportionate amount of pressure from the brake calipers, which makes control of the weight transfer slower and less predictable.

In my experience there's only 2 places where ABS in a race car shines. In the wet: you still want to avoid feeling it in the pedal for all the reasons above, but it gives you such a larger buffer for keeping the car under control while braking / entering a corner. And, stopping the flat spotting of inside front tires in certain corners where you really want to carry a good amount of brake pressure into the corner but the car is so unloaded on one side that without ABS after a couple laps you'll have a big flat spot.

With the motorsport ABS systems I don't doubt that if you spent a day working on a single corner under a finite set of tire, car and track conditions you could probably get the fully activated ABS to be better than a good driver for that one corner at that moment in time. However, every corner is different and the same corner changes lap by lap as conditions and tires change. The same programming that works for one corner at one time won't work for another corner at another time and that's why the motorsport ABS is good, but not a catch all for making the car go around the track as fast as it possible can. At least not with currently available technology.

Just my 2c anyway... Happy New Years everyone!

-mike

Originally Posted by DTMiller

There's a very good thread here: https://rennlist.com/forums/racing-a...-it-bad-2.html that talks about these issues and despite the very expert input from people who really really know what they are talking about it still gets really murky really fast; and you're asking the right question. It seems clear to me that there exist race cars where the ABS system is far superior to humans but the tricky part is figuring out whether you, the casual HPDEr or not-brand-new race car driver, are driving one of the cars where ABS is universally superior.

Originally Posted by jscott82

Thanks... Somehow I missed that thread in 2019..

Originally Posted by jscott82

Thanks... Somehow I missed that thread in 2019..

Originally Posted by DTMiller

Unforgiveable.

Originally Posted by jscott82

So, what I think I know now.
But once activated, how does it determine how to manage the tire.???
A) sensing real world conditions: IE releasing pressure until the wheel starts rotating again, the reappling pressure until lock is sensed again.

B) running through pre programed maps based on static assumptions (car weight, tire grip, brake COF), etc
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