[Zubeneschamali]

Originally Posted by MrDerp

ABS decided I was having a skid, but I believe that I got grip much sooner than the system believed I had it. The car was speeding up, I felt it slow down directly in response to my use of engine braking.

So you are better than the ABS system at sensing wheel spin and lock-up?

You are either superhuman or your ABS is broken.

[sambucus]

Guys abs is no good in a situation where all 4 wheels lock up. Brake assist will but is only a feature in modern cars.
So IMO engine braking and gently tapping brakes will shorten braking distances over abs

[MrDerp]

Originally Posted by Zubeneschamali

So you are better than the ABS system at sensing wheel spin and lock-up?

You are either superhuman or your ABS is broken.

No, I never said that. You're putting words in my internet mouth.

I said I believe that my ABS continued to prevent me from braking, causing the car to speed up on the hill, when the grip issue had passed. I was forced to intervene and slow the wheels myself.

I didn't sense wheel spin, I didn't sense lock-up, and I didn't sense grip. I was, however, sure as hell forced to try for grip myself, which I thankfully found under engine braking. This was brought about, not by some quick mechanical reasoning, but by my decision to come to a complete stop off the main road, rather than to attempt controlling the situation using the brakes. Plan B was a slightly blind turn up another hill into an estate (just before where I stopped) if grip continued to fail.

ABS is an excellent system, but it's still a computer governed by rules. It is not a replacement for driving skill. I'm not saying I'm a particularly skilled driver, but I had a good instructor and I maintain that my habit (note: not quick-thinking, habit) of always using the gears when I plan to come to a complete stop, stopped me from having an accident on that occasion.

[CiniO]

Lots of people in this thread seem to consufe situation of ABS kicking in, and situation of emergency braking where ABS is working fully.

If you are on slippery surface, and press brake pedal ABS might kick in (pedal might start to vibrate) but it doesn't mean that full braking force is applies already. It could have been only one of four wheel which skided (maybe because of oil patch or sth) and this caused ABS to work just on this one perticular wheel, but other 3 still don't use their maximum braking force. In that situation to increase braking force, you should depress brake pedal as strong as possible. This will increase braking force greatly.
I'm guessing that OP didn't do it, and therefore he didn't use all possible braking force.

[CiniO]

Originally Posted by Zubeneschamali

So you are better than the ABS system at sensing wheel spin and lock-up?

You are either superhuman or your ABS is broken.

Generally on ice ABS is not that great about stopping distance. You might stop sooner with wheels locked. As in cars with ABS that's impossible, you might try to fiddle with engine braking, and cause wheels to turn slower than actually car is moving, causing it to brake.

On loose surface (like snow, sand or gravel) braking without ABS is way more efficient that with it. Unfortuantely no moders car allow to turn off ABS easily. What I used to do in Mondeo was to take ABS fuse off to make it stop working.

[Viper_JB]

Think these say it all really
http://www.tyrereviews.co.uk/Tyre/Triangle/TR968.htm
http://www.tyrereviews.co.uk/Tyre/Triangle/TR918.htm
If the tyres can't get traction then the ABS pretty much has it's work cut out.

[smemon]

Originally Posted by sambucus

Guys abs is no good in a situation where all 4 wheels lock up. Brake assist will but is only a feature in modern cars.
So IMO engine braking and gently tapping brakes will shorten braking distances over abs

Have you ever tried engine breaking (clutch in, foot off brake) whilst you're in the process of crossing your fingers the car will stop in time before you hit something?

There's no time. You'll temporarily speed up doing it too. If ABS kicks in, bottom line is you can't afford to lose time taking your foot off the brake...

[sambucus]

Originally Posted by smemon

Have you ever tried engine breaking (clutch in, foot off brake) whilst you're in the process of crossing your fingers the car will stop in time before you hit something?

There's no time. You'll temporarily speed up doing it too. If ABS kicks in, bottom line is you can't afford to lose time taking your foot off the brake...

Picture this. Driving on ice at say 15kmph say 2nd gear decide to stop. Foot off accelerator gently tap brakes stopping distance will be shorter than jamming on brakes causing the abs to lock all 4 wheels.
I'd say it was far more likely OP had a 4 wheel lock up situation
Engine braking only works with foot off clutch btw!

[dingus12]

You do realize that your missing the whole concept of ANTI LOCK braking? as in the pulsating feeling you get when the abs system engages is the brake pressure being applied and let of rapidly so the wheels do not stop rotating which enable steering and more grip.

[sambucus]

Originally Posted by dingus12

You do realize that your missing the whole concept of ANTI LOCK braking? as in the pulsating feeling you get when the abs system engages is the brake pressure being applied and let of rapidly so the wheels do not stop rotating which enable steering and more grip.

Yes it's called antilock braking because it will stop a 1,2 and 3 wheel lock up unfortunately not a 4 wheel lockup. Hence previous poster disabling his abs for snow/ice driving

[dingus12]

Originally Posted by sambucus

Yes it's called antilock braking because it will stop a 1,2 and 3 wheel lock up unfortunately not a 4 wheel lockup. Hence previous poster disabling his abs for snow/ice driving

who's to say it's not a 4 channel system?

http://auto.howstuffworks.com/auto-p...ock-brake2.htm

[sambucus]

Ok Wikipedia says when abs is disabled locked up wheels can dig in causing braking distances to be shorter. So it seems I'm wrong about this. I had a 4 wheel lockup last winter with my abs on the 406 and a friend in 05 fiesta had the same problem. Were both of our abs systems faulty I wonder

[langdang]

Originally Posted by sambucus

Yes it's called antilock braking because it will stop a 1,2 and 3 wheel lock up unfortunately not a 4 wheel lockup. Hence previous poster disabling his abs for snow/ice driving

Why does it not work for 4 wheel lockup - it thinks the car is at a standstill?
IE it only knows the car is moving and up to 3 wheels are locked if 1 of the four is still rotating? Hmm, never thought about that before.

I think if all 4 wheels are going to be on ice or oil for the whole distance of the space you have to brake then you're pretty much gonna have to make the best of a bad situation, ABS or no ABS. But if there's even intermittent traction I'd still put my faith in ABS, personally.

[langdang]

Originally Posted by sambucus

So it seems I'm wrong about this. I had a 4 wheel lockup last winter with my abs on the 406 and a friend in 05 fiesta had the same problem.

You think, or you know? How do you know? Out of interest in these systems rather than looking for an argument.

[sambucus]

Originally Posted by langdang

You think, or you know? How do you know? Out of interest in these systems rather than looking for an argument.

Was so sure of myself there initially now it appears I've made a complete twat of myself.!!
Certainly interested in others opinions of course and would rather not hang on to my misconceptions.
As regards to think or know do you mean about my 4 wheels locking up last winter looking back the lads at work saw both wheels locked looking from one side only tho so yes was only assuming (although car was sliding straight) had no abs light too