More back end action
Discussion
Just another little point for any normal Porsche owners still here. A couple of recent posts have talked of using various means such as gear changes or sudden brake / throttle movements to up-root the back end of your car to counter understeer, (the front end pushing on), at low speed corners. You know to "bring the back end round a bit". Similarly we might be edging towards the "keep your foot planted if the back end goes" camp.
Just so there is no misunderstanding you will smash your car up if you try this at home.
See your cars as pretty ladies that you`re trying to have your end away with. Those of you lucky enough to have had a girlfriend will know they don`t take kindly to sudden movements. Neither does your car.
Even at half steering lock your car will pop into huge oversteer and proceed to spin on it`s own axis if you whack you foot on the gas in 1st gear from low speed. Initially it understeers a bit and then all of a sudden presto. And it`s not just the big bhp stuff. I was drifting at Silverstone this week in a - wait for it - 944. And even with race tyres on the back end popped straight out, just like like a z listers left breast at a film premier. Be delicate.
With regards the back end popping out, if you`re going to have any chance of catching it you`ll need to back off the throttle and let the rear tyres grip. Again, in my flame breathing 944 - I kid you not, that baby throws out nearly 85db at the exhaust on a static noise test, if you want the back end to swing out more you give it more gas, if you want it to come back in line you lift off the gas.
I really don`t mean to be patronising but just thought I`d speak out in case people started to think all these techniques worked and were viable options on the tarmac. If you`re taking up rallying on the loose stuff then be prepared to learn some wierd and wonderful tricks, including how to read roadsigns upside down, but as for the tarmac just concentrate on keeping it smooth and between the white lines.
Henry
Just so there is no misunderstanding you will smash your car up if you try this at home.
See your cars as pretty ladies that you`re trying to have your end away with. Those of you lucky enough to have had a girlfriend will know they don`t take kindly to sudden movements. Neither does your car.
Even at half steering lock your car will pop into huge oversteer and proceed to spin on it`s own axis if you whack you foot on the gas in 1st gear from low speed. Initially it understeers a bit and then all of a sudden presto. And it`s not just the big bhp stuff. I was drifting at Silverstone this week in a - wait for it - 944. And even with race tyres on the back end popped straight out, just like like a z listers left breast at a film premier. Be delicate.
With regards the back end popping out, if you`re going to have any chance of catching it you`ll need to back off the throttle and let the rear tyres grip. Again, in my flame breathing 944 - I kid you not, that baby throws out nearly 85db at the exhaust on a static noise test, if you want the back end to swing out more you give it more gas, if you want it to come back in line you lift off the gas.
I really don`t mean to be patronising but just thought I`d speak out in case people started to think all these techniques worked and were viable options on the tarmac. If you`re taking up rallying on the loose stuff then be prepared to learn some wierd and wonderful tricks, including how to read roadsigns upside down, but as for the tarmac just concentrate on keeping it smooth and between the white lines.
Henry
Hi Henry
With all of these wonderfully informative posts, I'm assuming things are a bit slow in the Uxbridge area
Tony Corletts wonderful 3.2 book gives some great instruction on driving that particular car and his golden rule is to never ever lift or break in a corner (fairly obvious stuff but stressed as even more important with the 911). Now I realise that not lifting is very different to nailing it, but how would you rescue serious oversteer in a 3.2 rather than a 944 - would you still lift to let the tyres re-grip?
With all of these wonderfully informative posts, I'm assuming things are a bit slow in the Uxbridge area
Tony Corletts wonderful 3.2 book gives some great instruction on driving that particular car and his golden rule is to never ever lift or break in a corner (fairly obvious stuff but stressed as even more important with the 911). Now I realise that not lifting is very different to nailing it, but how would you rescue serious oversteer in a 3.2 rather than a 944 - would you still lift to let the tyres re-grip?
If anyone wants expext instruction and to gain an understanding of the dynamics involved, there are several excellent 'coaches' who can help you gain/develop technique in the likes of Bernard Aubrey, Don Palmer, John Lyons, etc. They are IMHO money well spent and give you more control of your car and also confidence to drive a bit harder in tricky situations. Often the courses are run on private testing facilities with LOTS of run off shold things go pete tong.
The £300-£500 spent in developing yourself is often worth a lot more than the PSS9/DVD player/'sports' exhaust waiting on the shopping list.
All IMHO of course.
The £300-£500 spent in developing yourself is often worth a lot more than the PSS9/DVD player/'sports' exhaust waiting on the shopping list.
All IMHO of course.
ICSD said:
Hi Henry
With all of these wonderfully informative posts, I'm assuming things are a bit slow in the Uxbridge area
Tony Corletts wonderful 3.2 book gives some great instruction on driving that particular car and his golden rule is to never ever lift or break in a corner (fairly obvious stuff but stressed as even more important with the 911). Now I realise that not lifting is very different to nailing it, but how would you rescue serious oversteer in a 3.2 rather than a 944 - would you still lift to let the tyres re-grip?
Note the time of the first posting !!
It really depends on why the back end has broken away. If it`s because you were hard on the gas from a relatively slow speed corner then lift off the power. If its because you reached the limit of grip on a high speed corner then you need to keep the car balanced on the gas and ideally try to catch the car with the steering wheel by opening up the corner, not really possible on the road I`m afraid. In 95% of cases on the road people will be in the first situation as road cars will naturally understeer first unless you spin up the rear wheels. So in 95% of cases yes, lift of the throttle to stop the rear wheels spinning. In fairness as the back end comes round you`ll probably go into a spin the other way so the trick is not to put yourself in that position in the first place.
If you ever get the chance, go to a quiet corner of a big car park with no obstructions one night and drive round in fairly tight circles. Gently bring your speed up and you`ll feel (and hear) the front end losing grip so the car goes wide. Repeat the excersise you only this time get rolling slowly then floor the gas hard. This time the tyres will lose grip and after a brief moment of understeer the back end will swing round.
Road cars are designed to understeer first. Sudden changes in braking, steering or acceleration can upset the balance and allow the back end to give way. It doesn`t matter if it`s wet or dry, in the wet things just happen with less input from you.
In a 911 the trick is to go in slow and gently accelerate our of the corner. The one thing you can`t do is go in fast and then try and lose speed mid corner, (ie brake). Always try to do your braking in a nice straight line before the corner. The pride of nailing 1,000 corners at full speed is vastly out-weighed by the humiliation of standing by your car damaged and in a ditch when you get it slightly wrong once.
Henry
Ah! Burning the midnight oil to pass us these pearls of wisdom - very much appreciated thanks!
As per Fergus's suggestion, I have been considering a car control course where I guess you'd learn all this stuff.
Great to get your input though although, as you quite rightly say, the trick is not to put yourself in that situation in the first place.
As per Fergus's suggestion, I have been considering a car control course where I guess you'd learn all this stuff.
Great to get your input though although, as you quite rightly say, the trick is not to put yourself in that situation in the first place.
I would highly reccomend a bit of tuition. Driving on the limit in the wet and seeing what differing amounts of brake effort does to the balance of a car when understeering in a corner is good fun - when there is nothing to hit. Understanding it is reasonably easy. Mastering it is the hard bit.
If your driving a 4wd do not do any of the above.
The worst thing to do mid corner in a C4 is to lift, even if you have the rear starting to come around, nail the throttle and it will drag itself straight, a little steering twiddling will be required..!
I was just getting to grips with the C4S style, then its been changed for a C2S, Now beck to familiar techniques.
Graham
The worst thing to do mid corner in a C4 is to lift, even if you have the rear starting to come around, nail the throttle and it will drag itself straight, a little steering twiddling will be required..!
I was just getting to grips with the C4S style, then its been changed for a C2S, Now beck to familiar techniques.
Graham
Andy Walsh -www.Carlimits.com
Understeer. oversteer, power off oversteer etc., -you can try it all....you want to do a 360 (degrees, not Fezza)? Certainly sir -this is how....
Pray for a wet runway and have fun!!
Rgds
Mel
Understeer. oversteer, power off oversteer etc., -you can try it all....you want to do a 360 (degrees, not Fezza)? Certainly sir -this is how....
Pray for a wet runway and have fun!!
Rgds
Mel
henry-f said:
..such as gear changes or sudden brake / throttle movements to up-root the back end of your car to counter understeer..Henry
Ouch. Don't fancy using gear changes to counter understeer..some of the juciest TVR track accidents I've seen have been too quick a downshift on a Griff/Chimaera, the big V8s locking the rear wheels solid. Fiberglass, meet Mr Armco.
..however, leaving 911 aside, as you yourself have brought up the 924/944 series, doesn't it depend a bit on the suspension?
In the 924s I've recently aquired, the suspension seems to be Koni Specials with standard springs/torsion bar, and although in good condition, that lot is set-up so soft & squidgey, that you can be fairly "rough". Bit like a p1ssed student lady-friend after a fresher's disco, you have to be a bit brutal to keep her awake.
In our "other" car, a Cerbera set up fairly stiff, your theory applies absolutely. Before doing anything, even the gentlest prods of brake or accelerator, it's best to ask "May I?" first
DanH said:
Sundeep, its easy you just need to practise in Grand Tourismo. It's where Button learnt everything he knows.
I'm an xbox man myself ! so PGR2 was useful for getting a feel of the Ring, so I did recognise a fair bit when I finally went around...
but not a par of lap with the man Fergus teaching me the way around...
Tam Lin said:
In the 924s I've recently aquired, the suspension seems to be Koni Specials with standard springs/torsion bar, and although in good condition, that lot is set-up so soft & squidgey, that you can be fairly "rough". Bit like a p1ssed student lady-friend after a fresher's disco, you have to be a bit brutal to keep her awake.
Or alive in the case of the more elderly lover !
I`m a bad man.
Henry
sundeep said:
Sundeep, its easy you just need to practise in Grand Tourismo. It's where Button learnt everything he knows.
I'm an xbox man myself ! so PGR2 was useful for getting a feel of the Ring, so I did recognise a fair bit when I finally went around...
but not a par of lap with the man Fergus teaching me the way around...
I was kidding about learning car control from a game
PGR3 on the 360 is great though. I'm a complete addict.
I have a book about 911 driving (given as a gift), don't have it on hand so don't know the author or title immediately - he stated that the 911 pivots round a point directly between the front wheels (presumably centre of mass w.r.t. angular momentum?).
He also stated that the self-centring action of the steering means that if the back goes in a 2wd 911, you can simply let go of the steering wheel and grab it again once the car has naturally straightened itself out. Stupidly I tried this at *very* low speed mini-slide out of a mini roundabout, and it worked. And no, I'm not going to try that again unless I'm on a skid pan with John Lyon
I'm no driving god but usually drive through little slides here and there in mine - my trick is simply never make extreme inputs, either steering or braking... if the car starts to oversteer then a little less lock and a little less throttle (or even steady throttle) seems to work.
I have obviously been lucky, and it all points to a golden rule of never getting the car really unstable in the first place. A little bit of oversteer is fine and fun, but trying John Barker-esque photoshoot heroics is sure to end in tears. Aptly enough, I remember vividly the article in Performance Car with JB himself standing ruefully next to a 993 in a ditch. Given his car control ability, and that he lost the 993 in the dry, certainly focuses the mind somewhat...
He also stated that the self-centring action of the steering means that if the back goes in a 2wd 911, you can simply let go of the steering wheel and grab it again once the car has naturally straightened itself out. Stupidly I tried this at *very* low speed mini-slide out of a mini roundabout, and it worked. And no, I'm not going to try that again unless I'm on a skid pan with John Lyon
I'm no driving god but usually drive through little slides here and there in mine - my trick is simply never make extreme inputs, either steering or braking... if the car starts to oversteer then a little less lock and a little less throttle (or even steady throttle) seems to work.
I have obviously been lucky, and it all points to a golden rule of never getting the car really unstable in the first place. A little bit of oversteer is fine and fun, but trying John Barker-esque photoshoot heroics is sure to end in tears. Aptly enough, I remember vividly the article in Performance Car with JB himself standing ruefully next to a 993 in a ditch. Given his car control ability, and that he lost the 993 in the dry, certainly focuses the mind somewhat...
cyberface said:
He also stated that the self-centring action of the steering means that if the back goes in a 2wd 911, you can simply let go of the steering wheel and grab it again once the car has naturally straightened itself out.
What actually happens is that as the back end slides out the steering will go to full lock, turning into the skid. That`s exactly what you do when you`re drifting a car. (You then try to keep the rear wheels spinning and steer with a combination of throttle and steering input).
The trick to controling a slide is to slightly predict what the car is going to do and turn the steering wheel accordingly. If you`re reacting to a change of direction with the steering wheel you`re probably a bit late and that`s what causes fishtailing and the rear end snapping back and oversteering in the opposite direction, usually to a full spin.
It all depends on how much the back end swings out.
Henry
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