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-   -   ABS limiting at the track/AX? (http://www.focusfanatics.com/forum/showthread.php?t=121708)

eventerke 05-13-2007 10:09 PM

ABS limiting at the track/AX?
 
Had a great day at the NASA AX today - without going into a long drawn-out story (yet [hihi] ), how many of you find the ABS kicking in when you're trying to brake at the limit and screwing you up?
I'm starting to get a good feel for using the weight transfer in heavy braking to get the back end of the car rotating, but I'm finding that at the absolute limit the ABS kicks in and destroys the balance I'm trying to use.
WD40 mentioned pulling the ABS fuse puts the braking system balance in a 50/50 limp mode, and is a *bad* idea.

Do most of you just deal with this? Is the ABS really telling me the truth on the braking limit?

tua03332 05-13-2007 11:00 PM

i ended up upgraded my front discs and then pulling the one fuse and found that the biase is mostly even but does favor locking up the back. Play around with it and use which ever feels better to you

Egz 05-14-2007 11:30 AM

ABS? What's that? [;)]

If its kicking in, I would assume you just exceeded threshold braking.

WD40 05-14-2007 11:44 AM

^^^Exactly...you've found the limit.
What tires are you running??

DON'T pull that fuse (46) and expect to stay on track. (or anywhere near on track)
I tried that a month ago at a threshold braking excercise during our test and tune.
While I got out of the hole like a bullet (no TC),
the instant I hit the brakes the car turned 90° sideways since the rears locked up immediately.
Again, I stress...never ever try this on a road course or autocross,
and expect your car not to sustain massive amounts of damage as you leave the course.

The ABS is nothing short of phenomenal on the SVT, especially with the given large rotors.
I'll bet your tires are the limiting factor at the moment, which is why I asked what you were running.

JRODSVT 05-14-2007 12:35 PM

neither have I but then again i probably don't push my car as hard as others do.

WeeAsp 05-14-2007 01:03 PM

Quote:

Originally Posted by WD40 (Post 1583369)
^^^Exactly...you've found the limit.
What tires are you running??

DON'T pull that fuse (46) and expect to stay on track. (or anywhere near on track)
I tried that a month ago at a threshold braking excercise during our test and tune.
While I got out of the hole like a bullet (no TC),
the instant I hit the brakes the car turned 90 sideways since the rears locked up immediately.
Again, I stress...never ever try this on a road course or autocross,
and expect your car not to sustain massive amounts of damage as you leave the course.

The ABS is nothing short of phenomenal on the SVT, especially with the given large rotors.
I'll bet your tires are the limiting factor at the moment, which is why I asked what you were running.

Concur. You found the limit. Tires are also a BIG contributor.

That said. Threshold braking is an art.

Your car demonstrates is highest braking ability right at the point of lock-up or just before the ABS kicks activates.

I am not saying that you do, but most people brake with the ball of their foot. As a result, they are using about 7X the pressure necessary to effectively slow the car.

Try using your toes. They are just as, if not more sensitive, than your finger tips (step on a sharp rock and you jump - put your hand on a sharp rock and you go "OW!"). Using your toes will allow you to be more progressive with your braking and likely not upset the car as much.

A lot of people "heel and toe" using thier toes. Unless you have a lot of time to practice, it takes a while to master. I personally have never been able to get it right.

As for the ABS fuse. WD40 is right. The SVT ABS system is phenomenal. You'll create more problems for yourself by disabling it. Not only from a systems standpoint, but also one of conditioning. Your body (muscle memory) is trained to react when the ABS kicks in. Remove the ABS, not only do you flat spot tires, but your reaction time is slowed as you process how to proceed.

The toes knows. [:D]

eventerke 05-14-2007 01:06 PM

OK - thanks for the replies!

I'm running crappy, greasy (when they get hot) Falken Ziex's. They were my "learning set" and now I feel I'm ready to step up to a set of Azenis.
Really helped to learn what it feels like to slide the car around a bit, at least [driving]!

I'm hoping to kill them good and dead this Sunday, then I'll *have* to get a new set. They're holding a raffle (AX is a benefit for the JimmyV foundation), and one of the prizes is $500 for tires at Discount Tire - you can guess what I'm hoping for!

WeeAsp 05-14-2007 01:08 PM

Can't go wrong with a $500 credit toward tires.

Good luck!

SpeedOften 05-14-2007 01:34 PM

If you want to disable TC.. get Tom's tune...
and +2865983698 to not pulling the TC/abs fuse... I tried doing once as well and the rear does become quite happy - almost kicked a few cones b/c of it...


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