The online racing simulator
Anti-skidding lessons
(120 posts, started )
#51 - axus
Who said anything about accelerating as much as possible while correcting a slide? Tristan and Ajp are talking about just having a bit of gas so the car is stable. Furthermore, I just deduce that you're a clot because you seem to just blab on your own thing when I'm arguing pure physics with you.
Quote from ans7812 :My point exactly. If you are turning a corner on snow covered ground, and start to slide as a result of LOSS OF TRACTION because of the snow (turning too sharply etc.) not THROTTLE LIFT OVERSTEER, applying more throttle won't do anything because the car is ALREADY in the SLIDE. There is no SEVERE weight shift to begin with so adding throttle will only SPIN the tires even MORE.

Oh god... how many times do we have to go through this? Even if the oversteer isn't caused by removing the throttle adding some can still help because when you apply power weight is still shifted to the rear of the car.

If your going to ignore Tristan and I then fine but at least listen to Axus because not only does he have a good understanding of what's going on but can explain it in terms of simple physics.
#53 - axus
Quote from ajp71 :Oh god... how many times do we have to go through this? Even if the oversteer isn't caused by removing the throttle adding some can still help because when you apply power weight is still shifted to the rear of the car.

Not only that but 0 throttle doesn't mean 0 longitudinal acceleration because you still have friction! :doh:
Quote from ajp71 :Oh god... how many times do we have to go through this? Even if the oversteer isn't caused by removing the throttle adding some can still help because when you apply power weight is still shifted to the rear of the car.

If your going to ignore Tristan and I then fine but at least listen to Axus because not only does he have a good understanding of what's going on but can explain it in terms of simple physics.

By adding throttle while sliding in the snow, sure it will shift weight to the back but it will also spin the tires faster and therefore make it unlikely to gain traction, especially in snow! Take your car out when it snows for gods sake. Slide it. Now while in the slide, add a little bit of throttle! or however much you think you need! You will notice that if there is any significant snow cover, your tires will spin! I understand the physics, you need to understand reality.
#55 - axus
Rubbish. On a loose surface especially, it's best to add power. Power digs the tyres in and gives them more lateral grip. This applies to rally and snow.

Furthermore, say you are about to cross a puddle, with one pair of tyres (ie. left or right) or all tyres, what is the safest thing to do? Stabilize the car in neutral acceleration before crossing the puddle. If you lift off completely, you will be slowing down, however slightly.

This also applies to firm surfaces that are very slippery if you get into a slide. For example ice. If you lift off completely, there is a HUGE chance of spinning, because
a) your rear tyres are loaded with slowing down the car, however slightly
b) there is more load on the outside rear tyre, which while slowing the car down may cause some undesirable torque to rotate the car into a slide in the opposite direction once you correct the initial slide
c) there is weight transfer to the front because you lifted.

On road, again, based on the same principles, you should never lift off to more than neutral acceleration. In most instances, you wouldn't even need to do that though.
The best way to make a sliding or spinning tyre regain traction is to match its rotational speed to the speed of travel as closely as possible. Simple lifting off everything and steering the car straight doesn't do this, and it makes the car so unstable, when grip does come back it will come back with a bang. A large number of times, when you see people overcorrecting or fishtailing from side to side it's because they just let go of the throttle. It's even better to declutch and steer it straight than just lift off everything, but I wouldn't do that either myself.
#57 - AJS
All i can say is when you will face such a situation you will not think about theory you will just do what your guts tell you

Not so long ago i experienced some sudden unexpected oversteer with my BMW 318is.

I drove onto the Autobahn and it just started to rain. The tarmac was very slippery and different layers which had been repaired ... so old and new tarmac there. A bit downhill as well.

I was driving through the turn and suddenly lost the rear ... i was doing 80 kmh already.

I think i had almost a nice 45 degree slip angle and a vision of my car kissing the armco. Then my arms magically did rotate by themselves and i modulated the throttle a bit (i think first a bit off the gas then stepped on it just a tad).

End of story : car straight and safe ... nothing happend
Quote from sinbad :The best way to make a sliding or spinning tyre regain traction is to match its rotational speed to the speed of travel as closely as possible. Simple lifting off everything and steering the car straight doesn't do this, and it makes the car so unstable, when grip does come back it will come back with a bang. A large number of times, when you see people overcorrecting or fishtailing from side to side it's because they just let go of the throttle. It's even better to declutch and steer it straight than just lift off everything, but I wouldn't do that either myself.

Pushing in the clutch is the worst thing you can do.
Quote from AJS :All i can say is when you will face such a situation you will not think about theory you will just do what your guts tell you

Not so long ago i experienced some sudden unexpected oversteer with my BMW 318is.

I drove onto the Autobahn and it just started to rain. The tarmac was very slippery and different layers which had been repaired ... so old and new tarmac there. A bit downhill as well.

I was driving through the turn and suddenly lost the rear ... i was doing 80 kmh already.

I think i had almost a nice 45 degree slip angle and a vision of my car kissing the armco. Then my arms magically did rotate by themselves and i modulated the throttel a bit (i think first a bit off the gas then stepped on it just a tad).

End of story : car straight and safe ... nothing happend

You're right. Why don't we stop arguing, continue to do what we've been doing, and then share our experiences of what happened. I'm sure we will all be fine. You do what you have been doing, I'll do what I've been doing. It has seemed to work for me all this time so i see no problem in continuing to do so. Nothing serious has happened to me and I have never been in an accident. I'm sure your methods work for you. I hope none of us find ourselves in a life or death situation on the road. Safe driving.
Quote from ans7812 :Pushing in the clutch is the worst thing you can do.

No, just lifting is worse. At least whilst declutched you have a neutrally balanced car and driven wheels which will more quickly attempt to match the speed of travel. Rather than effectively braked driven wheels and a front heavy car.
What did I do
Quote from sinbad :No, just lifting is worse. At least whilst declutched you have a neutrally balanced car and driven wheels which will more quickly attempt to match the speed of travel. Rather than effectively braked driven wheels and a front heavy car.

No, having the clutch in during a turn is the first thing you are told NOT to do when driving a standard. THAT is something i HAVE experienced.

Again rainy day. Only had my permit, was driving a standard on public roads for the first time. I wanted to make a left turn, not speeding or going too slow, normal turning speeds. Made the mistake of depressing the clutch just after i turned in and PHEWWWWWW the ass slides out, countersteered, the car straightened out no problem and we kept going.
Quote from ans7812 :No, having the clutch in during a turn is the first thing you are told NOT to do when driving a standard. THAT is something i HAVE experienced.

Again rainy day. Only had my permit, was driving a standard on public roads for the first time. I wanted to make a left turn, not speeding or going too slow, normal turning speeds. Made the mistake of depressing the clutch just after i turned in and PHEWWWWWW the ass slides out, countersteered, the car straightened out no problem and we kept going.

No, you hit the clutch while in the corner, but when you're starting to slide they told me it's best to dump the clutch. Because it will indeed regain grip more easily than loaded wheels.
Quote from sgt.flippy :No, you hit the clutch while in the corner, but when you're starting to slide they told me it's best to dump the clutch. Because it will indeed regain grip more easily than loaded wheels.

Dumping the clutch means letting it out quickly and rapidly. (taking your foot off the clutch)
I agree with the clutch comment - can help stabilse a sliding car.

If you car starting sliding because you pressed the clutch whilst driving at a sensible speed might I suggest you look at your wheel alignment!
Quote from ans7812 :Pushing in the clutch is the worst thing you can do.

Not really, applying far too much or no throttle will end up unstabilising the rear of the car far worse although you will loose throttle control and if your on the limit when you dump the clutch in you may end up with weight transfer issues.

Quote from ans7812 :I'm sure we will all be fine. You do what you have been doing, I'll do what I've been doing.

Well if you're not going to react to a situation properly then simply don't put yourself there in the first place, not that you should have any reason to at anything other than low speed accept on a race track. If you're going to drive on the limit you first must know how to control the car and drive it on and recover from going slightly over the limit, unfortunately I think if you actually did find yourself oversteering at high speed properly on the limit you'd lift off and wrap yourself round a tree pretty quickly.

I think the luckiest escape I've ever seen in person was caused by a 944 lifting off to try to avoid a spinning car ahead of him, he'd of been doing about 90mph at the time and despite being an experienced driver who usually wouldn't make such a silly mistake and in hindsight it would have been better to deliberately let the car run wide and try to hold it on the grass or even just accept he may have to T-bone the spinning car. The lift off oversteer was uncatchable and the car spun across the grass towards the inside barrier and marshals, post loosing almost no speed. The car hit the barrier at 90 degrees and flattened it, it launched the car through the marshals post and down into a hard landing. The 3 marshals had just managed to run from it in time and he only suffered minor injuries but had to be cut from the car. That was the result of a passenger side impact in a race prepared car with full rollcage, 6 point harnesses and bucket seat with side impact neck protection at a race track with a good run off area crash barriers and very quick paramedic and rescue response. If anyone of those factors wasn't there then there's no doubt you would be looking at a potential fatality. If you did that on the road without those safety measures you wouldn't stand a chance, is it really worth be stubborn and not learning to deal with this kind of situation?
Quote from tristancliffe :I agree with the clutch comment - can help stabilse a sliding car.

If you car starting sliding because you pressed the clutch whilst driving at a sensible speed might I suggest you look at your wheel alignment!

You misunderstood. I was already IN the turn and made the mistake of pushing in the clutch during the turn.


@last post. Yes, obviously you wouldn't want to release the clutch like that because it will throw the balance of the car off. Thats not what i'm talking about. I'm saying, you should have no reason to put the clutch in during a turn anyway, you should already be in gear and braking/have braked already. Pushing the clutch in during a turn at any significant speed especially on a wet road surface like i experienced, is recipe for disaster
What the correct or best reaction is depends on so many factors, it is entirely pointless to have an argument over. Saying that "when you slide" you should always lift the throttle completely is equally wrong to saying you should always apply neutral throttle or always accelerate a little. It all depends on what situation you are in, what kind of car you're driving and how it behaves, what kind of surface you're driving on, etc etc etc.

Now stop being stupid and go back to topic, which is about skidding lessons. I think everyone getting a driving license should have a mandatory skid training, if only so that a car on the limit is nothing completely new to the driver. It's better if he has the chance to react but react wrong (or maybe right), than if he couldn't react at all because of complete and utter shock.
Quote from ans7812 :You misunderstood. I was already IN the turn and made the mistake of pushing in the clutch during the turn.

Well if your spinning from disengaging drive then you clearly already need that throttle to keep the car balanced and if you're not on the limit of adhesion you shouldn't have an issue.

Quote :
@last post. Yes, obviously you wouldn't want to release the clutch like that because it will throw the balance of the car off. Thats not what i'm talking about. I'm saying, you should have no reason to put the clutch in during a turn anyway, you should already be in gear and braking/have braked already. Pushing the clutch in during a turn at any significant speed especially on a wet road surface like i experienced, is recipe for disaster

No if you read it all that was caused by lifting his foot off the throttle, and not declutching, exactly what you reckon you should do. Had he declutched it would probably have been catchable.
Quote from ajp71 :Well if your spinning from disengaging drive then you clearly already need that throttle to keep the car balanced and if you're not on the limit of adhesion you shouldn't have an issue.

No. I slid because by depressing the clutch, essentially you are disengaging the transmission from the engine and allowing the drive wheels to spin freely with no resistance (engine). Because of the wet surface and the ability for the rear tires to spin freely, the rear got loose and i started to slide. That is why depressing the clutch in a turn is bad because it lets the drive wheels spin free.



Quote from ajp71 : No if you read it all that was caused by lifting his foot off the throttle, and not declutching, exactly what you reckon you should do. Had he declutched it would probably have been catchable.

What are you talking about? I was not referring to your situation at all. I was referring to the first part of you post, not your experience.
I think someone needs to give up the arguement while he can still recover his dignity. Or I guess maybe it's already too late and it's a fight to the death now.
Lol. and give up fighting for the truth? AndriodXP said the most sensible thing so far. He stated that it entirely depends on the circumstance and he is entirely correct. It's not right to say you should ALWAYS do this or ALWAYS do that. We are all wrong. Lets drop that argument and continue with the next stupid one.

I will say one thing. Depressing the clutch in a turn is NOT the right thing to do. Anyone who knows anything about driving a standard knows this. And ajp, before you start talking about your Porsche friend, I am not talking about emergency situations. When you drive around town or even on the track, any racer/driver knows that turning with the clutch in is not a good idea.
Quote from ans7812 :No. I slid because by depressing the clutch, essentially you are disengaging the transmission from the engine and allowing the drive wheels to spin freely with no resistance (engine). Because of the wet surface and the ability for the rear tires to spin freely, the rear got loose and i started to slide. That is why depressing the clutch in a turn is bad because it lets the drive wheels spin free.

Yes and the wheels will choose to spin at the road speed, meaning they are going to slip a lot less than if you just lift off the throttle. If you declutch you will be decelerating slowly, the deccelerative force will be made up of the rolling resistance and drag, which is considerably less than if you include the engine braking force of releasing the throttle, the result being a little bit of weight transfer to the front and no tire slip rather than a huge weight transfer to the and massive tire slip. What you want is weight transfer to the rear and little wheel slip so witch action gives you the best result? Of course the answer to this question may change depending on the situation but it usually involves holding or adding a bit of throttle and never involves leaving the pedals alone. This is a really silly myth that will never seem to go away even if you've gone past the point of being able to hold a slide you can still do something to minimize the results of the spin, be they simply putting the clutch in so you can get the car out of danger when you've regained control or applying a bit of brake to stop the car shooting backwards into the path of another car or wall or even to just accepting it's going to be a biggie and turning it off. This whole attitude of just trying to teach what is 'safe' to tell someone really pisses me off, as did the driving theory about car control, if you're going to tell someone not to put the clutch in you then have to tell them what to do, else they'd be safer just putting the clutch in
Quote from ajp71 :Yes and the wheels will choose to spin at the road speed, meaning they are going to slip a lot less than if you just lift off the throttle. If you declutch you will be decelerating slowly, the deccelerative force will be made up of the rolling resistance and drag, which is considerably less than if you include the engine braking force of releasing the throttle, the result being a little bit of weight transfer to the front and no tire slip rather than a huge weight transfer to the and massive tire slip. What you want is weight transfer to the rear and little wheel slip so witch action gives you the best result? Of course the answer to this question may change depending on the situation but it usually involves holding or adding a bit of throttle and never involves leaving the pedals alone. This is a really silly myth that will never seem to go away even if you've gone past the point of being able to hold a slide you can still do something to minimize the results of the spin, be they simply putting the clutch in so you can get the car out of danger when you've regained control or applying a bit of brake to stop the car shooting backwards into the path of another car or wall or even to just accepting it's going to be a biggie and turning it off. This whole attitude of just trying to teach what is 'safe' to tell someone really pisses me off, as did the driving theory about car control, if you're going to tell someone not to put the clutch in you then have to tell them what to do, else they'd be safer just putting the clutch in

I think the conflict arises in your misunderstanding my posts. I'm not talking about clutching in during a slide or a spin or anything like that. Read my last post. My point is, in general, while driving normally, be it on a track or not, going through a turn with the clutch in is not a sensible thing to do.

Maybe you're right about depressing it during a slide, maybe you're wrong. Thats not the point. I'm not talking about doing anything with the clutch during a slide. Thats a whole other story that you are confusing with my scenario.
Quote from ans7812 :No. I slid because by depressing the clutch, essentially you are disengaging the transmission from the engine and allowing the drive wheels to spin freely with no resistance (engine). Because of the wet surface and the ability for the rear tires to spin freely, the rear got loose and i started to slide. That is why depressing the clutch in a turn is bad because it lets the drive wheels spin free.

Um, no. It doesn't work like that I'm afraid. Have you got Skip Barber's book? May I suggest a read is in order?
Quote from ans7812 :I think the conflict arises in your misunderstanding my posts. I'm not talking about clutching in during a slide or a spin or anything like that. Read my last post. My point is, in general, while driving normally, be it on a track or not, going through a turn with the clutch in is not a sensible thing to do.

Again, no. Whilst driving normally on the road, you can do what you damn well like with the clutch. Coast through any corner with absolutely no chance of anything untoward happening (other than being in the wrong gear later, and holding up learners). Pressing the clutch whilst driving normally (or lifting off the throttle) won't do anything bad.

Normally, in this case, is taken to be sensible road speeds within the prescribed limits and regulations in force. Not hooning about anywhere near the limit at all. Sort of like being in a queue of cars behind a granny.

Anti-skidding lessons
(120 posts, started )
FGED GREDG RDFGDR GSFDG