April 2015 vfacts - Commodore 6th, Falcon nowhere

[castellan]

Originally Posted by asagaai

I come from a background of driving a rally car- and yes, in dirt I would prefer no ABS, good to dig the tyres in gravel when punching hard on gravel roads- and abs is no good for that style of driving.

But come on- driving a good modern car with abs on the road, wet etc. You cannot beat abs, in the real world.

A human confronted with a real emergency, if a good driver ,will react fast, hit the anchors, invariably too hard and lock up, and if a good driver, react fast, release the brakes and then re-apply. ( In a sense, an organic slow abs system).

Even driving in dry nowadays in a modern sorted abs car, and going into corners too hard, abs wonderfully modulates wash off of speed while enabling total steering control- drove an FGX XR8 really hard into corners and under heavy braking with abs modulation while turning- the abs wonderfully modulates retraction of speed while steering in total control- almost boring- ford have got this abs system working wonderfully on the FGX XR8.

I remember years ago going very hard into a tight bend at the edge of adhesion in an old GT Mk 11 1.6 rally car with the saide draft webbers, no brake assistance-all brake pressure from my right foot. A muppet swung into my lane without looking, leaving me nowhere to go- hit the anchors, resulting in lockup, while also at that point sliding sideways through the corner. Then quick releasing, re applying brakes, while working the sideways slide, and slid around the corner and threaded a gap. This 1 incident was probably the greatest bit of driving I have ever done- or not- (and I still remember it as a burning memory) and gave me a huge rush controlling the slide and lockup at the same time while threading a gap while all that was happening.

But truthfully had I been in a car with good abs it would have been far less dramatically controlled, but I would not have had the adrenalin rush and ultimate satisfaction of controlling a piece of machinery at speed that was a handful.


I like to think I am a good driver, I turn traction control off to have fun in wet, 4 wheel drifting etc in appropriate locations, but good sorted abs on tarmac is a no brainer...enables you to drive even faster.

One of reasons why abs is probably not allowed in some racing formulas is that it is fun to see racers pushing and locking up and getting all over the place but fighting the lockup in a corner- abs takes away this drama and on the roads that's a good thing, but that spectacle is great on the track.

I am not bagging ABS but just pointing out the facts.
A mate of mine was just about run over by an ABS Jeep on a dirt road, the dude could not control it because of the ABS. I seen it all happening and could see how the ABS made this loose control over what he was trying to do.
On good roads under 30 KM/H ABS is a looser, maybe not all ABS systems but some are. what happens is under wheel rotation it detects lock up and releases, but the wheel has to do a full rotation at less strength braking power until it detects again.
The brake thumps donk donk donk donk before it stops and each donk is a brake release, I can out brake it by 1/4 the distance or half and a make that can drive backs me up on this as a fact, I once said hell I nearly ran into someone because of the bloody ABS is to slow to react and he said he has the same thing happen to him. I seen him loose his VS SS ute once coming around a sharp bend on the race track, I am sure what happened was the lean of the car was very much and it pulled on the proportioning valve mid right hand corner locking the rear a touch, he came back spinning out saying did you see that, I sad yep ! the VS SS ute does not have a rear sway bar and they lean over very much more so.

Hell I know what ABS is capable of and what it is not, than to have some twerps of the street try to inform me of something that they think I don't know of.
I was doing around 220 KM/H once in the rain on a badly puddled road, just testing mind and I just slammed on the ABS as hard as I could, now that was impressive as to the best points of ABS being just magic.

To know a cars capability's is a good thing as that way you know what it can and can't do.

Most people drive in total ignorance, tyre pressures all over the place could not care what tyres they put on and I could go on and on.

[prydey]

Originally Posted by castellan

what happens is under wheel rotation it detects lock up and releases, but the wheel has to do a full rotation at less strength braking power until it detects again.

i don't think the wheel needs to do a full rotation.... you can feel the modulation, thats not a full rotation.

Originally Posted by castellan

The brake thumps donk donk donk donk before it stops and each donk is a brake release, I can out brake it by 1/4 the distance or half

ok. i'd be curious to know how you tested this theory.

[castellan]

Originally Posted by prydey

i don't think the wheel needs to do a full rotation.... you can feel the modulation, thats not a full rotation.



ok. i'd be curious to know how you tested this theory.

It feels like a full wheel rotation it may not be a full but it sure feels like it when you are nearly going to run up the rear of another car.

It's not a theory, it a fact as each donk you hear is the less brake power.

Just toddle along at 30 km/h and slam on the brakes, not all ABS is the same as some are more advanced than others.

As I just mentioned it once to my mate and he said he had the same experience him self.

[Spammy]

Originally Posted by castellan

I seen him loose his VS SS ute once coming around a sharp bend on the race track, I am sure what happened was the lean of the car was very much and it pulled on the proportioning valve mid right hand corner locking the rear a touch, he came back spinning out saying did you see that, I sad yep ! the VS SS ute does not have a rear sway bar and they lean over very much more so.

Hell I know what ABS is capable of and what it is not, than to have some twerps of the street try to inform me of something that they think I don't know of.


To know a cars capability's is a good thing as that way you know what it can and can't do.

on.

Can you explain how pulling on the brake proportioning valve locked the rear brakes. As I understand it, pulling on the valve releases the brake pressure to the rear to stop the back end locking up.

And you are completely wrong on abs full rotation story.

[Kieron]

Originally Posted by Spammy

Can you explain how pulling on the brake proportioning valve locked the rear brakes. As I understand it, pulling on the valve releases the brake pressure to the rear to stop the back end locking up.

Thats what I would have thought too. Potentially I guess, heavily loading one wheel in a when cornering could trigger the proportioning valve to open

And you are completely wrong on abs full rotation story.

Definitely wrong. ABS has a 'tone ring' with many teeth that will trigger brake release on lockup.