Scary 911 moment
Discussion
Hi all,
I would describe myself as an enthusiastic, but overall relatively cautious driver. I am new to the Porsche experience having bought a 911 997 Carera S about 6 months ago.
At the weekend the following happened:
- Late Sunday afternoon on a clearish stretch of dual carriage way. PASM is on (as it always is!, and I believe the Sports Chroro was not engaged)
- It had rained lightly in the morning, but no surface water
- I come off a roundabout in second gear and enter a stretch of clear motorway doing roughly 40mph (at around 4k revs I suppose)
- Heading straight (or very nearly) I floor it and instantly the back end swerves violently lurching the car to left, then to the right (towards the centre section). Eventually I come to a halt at 90 degrees across the road
Thankfully there was no one directly behind me and I was able to move away very gingerly.
I have heard the usual tales of old 911's being a challenge to drive but honestly I was shocked at a) how little it took to release the back and and ii) how disorderly it was when it happened.
I am convinced the car is trying to kill me, and have taken to driving like a monk.
Thoughts and experiences from other 911 owners please!
I would describe myself as an enthusiastic, but overall relatively cautious driver. I am new to the Porsche experience having bought a 911 997 Carera S about 6 months ago.
At the weekend the following happened:
- Late Sunday afternoon on a clearish stretch of dual carriage way. PASM is on (as it always is!, and I believe the Sports Chroro was not engaged)
- It had rained lightly in the morning, but no surface water
- I come off a roundabout in second gear and enter a stretch of clear motorway doing roughly 40mph (at around 4k revs I suppose)
- Heading straight (or very nearly) I floor it and instantly the back end swerves violently lurching the car to left, then to the right (towards the centre section). Eventually I come to a halt at 90 degrees across the road
Thankfully there was no one directly behind me and I was able to move away very gingerly.
I have heard the usual tales of old 911's being a challenge to drive but honestly I was shocked at a) how little it took to release the back and and ii) how disorderly it was when it happened.
I am convinced the car is trying to kill me, and have taken to driving like a monk.
Thoughts and experiences from other 911 owners please!
Thanks for all the replies.
Lesson learned and humble pie in the oven.
I was probably slightly exagerating when I said that the throttle was floored, but the rear end didn't come out on its own.
Some good content here around this topic, which echoes what has been said so far
http://www.pistonheads.com/gassing/topic.asp?t=664...
Lesson learned and humble pie in the oven.
I was probably slightly exagerating when I said that the throttle was floored, but the rear end didn't come out on its own.
Some good content here around this topic, which echoes what has been said so far
http://www.pistonheads.com/gassing/topic.asp?t=664...
jamieduff1981 said:
As the others have said, it's a sudden "flooring" that caused this, coupled with likely slow reaction times.
My Cerbera has easily enough power to do this, and even on a cold dry day will break traction at around 50mph in 2nd gear as the revs rise taking the torque with it and suddenly the torque applied to the wheels exceeds the traction available. Just wang the accelerator open suddenly and it'll do it in 4th on a damp road. Progressively open the throttles, allowing weight to transfer to the rear wheels and load them up allows much more power to be applied - but even foot to the floor in 3rd will result in loss of traction on a dry road. That's all fine - it's a TVR and anyone who doesn't expect it will soon be a statistic.
My XFR-S on the other hand is far more dangerous. It's a very well sorted chassis and about as much fun as a family car can be to drive. However - the fact is that with over 500lb.ft of torque from a supercharged 5 litre with a very non-German throttle response, no turbo lag to soften inputs, coupled with RWD via an active limited slip differential it will break traction on both rear wheels with either sudden OR wide throttle opening from pretty much any RPM in the wet, which can be quite alarming at first, yawing the car quite violently before the full-granny-mode DSC even wakes up. The DSC will prevent any drama if the over-use of power is gradual, but doing what you did OP will have the car snaking its way up the road with both rear tyres alight easily.
In the nicest possible way - you are still getting used to a high performance car - you've done the worst thing possible. Damp road (apart from aquaplaning potential, I personally find that a damp road is as slippery as a full wet one - if the tyres can disperse the water then it's entirely down to whether the compound grips the tarmac or not. Dry good, water molecules in between tyre and tarmac bad), low gear, revs just where a decent sized naturally aspirated engine makes its best torque or thereabouts and then you wellied the throttle wide open without managing the weight transfer.
If you're reactions are good (and you have experience) you can prevent the fishtailing-come-spin by undoing the stupid thing you just did - i.e. immediately put the throttle back where you had it before making the mistake. Dipping the clutch if you have 3 pedals works too. Both of these need to be done before the yaw angle gets too far. You also need to be right on the ball with your corrective steering and unwinding thereof. Many people catch the first yaw but are too slow to unwind it as the back end comes back in again and they swing the other way through a combination of angular momentum the car builds up and their own steering input encouraging it.
What you need to do is explore what the car can cope with gradually. Open the throttle a little bit more each time you leave a roundabout in various conditions and you'll learn what the car can do. Just going straight for full throttle is something that only a slow car lets you away with.
Thanks, great input.My Cerbera has easily enough power to do this, and even on a cold dry day will break traction at around 50mph in 2nd gear as the revs rise taking the torque with it and suddenly the torque applied to the wheels exceeds the traction available. Just wang the accelerator open suddenly and it'll do it in 4th on a damp road. Progressively open the throttles, allowing weight to transfer to the rear wheels and load them up allows much more power to be applied - but even foot to the floor in 3rd will result in loss of traction on a dry road. That's all fine - it's a TVR and anyone who doesn't expect it will soon be a statistic.
My XFR-S on the other hand is far more dangerous. It's a very well sorted chassis and about as much fun as a family car can be to drive. However - the fact is that with over 500lb.ft of torque from a supercharged 5 litre with a very non-German throttle response, no turbo lag to soften inputs, coupled with RWD via an active limited slip differential it will break traction on both rear wheels with either sudden OR wide throttle opening from pretty much any RPM in the wet, which can be quite alarming at first, yawing the car quite violently before the full-granny-mode DSC even wakes up. The DSC will prevent any drama if the over-use of power is gradual, but doing what you did OP will have the car snaking its way up the road with both rear tyres alight easily.
In the nicest possible way - you are still getting used to a high performance car - you've done the worst thing possible. Damp road (apart from aquaplaning potential, I personally find that a damp road is as slippery as a full wet one - if the tyres can disperse the water then it's entirely down to whether the compound grips the tarmac or not. Dry good, water molecules in between tyre and tarmac bad), low gear, revs just where a decent sized naturally aspirated engine makes its best torque or thereabouts and then you wellied the throttle wide open without managing the weight transfer.
If you're reactions are good (and you have experience) you can prevent the fishtailing-come-spin by undoing the stupid thing you just did - i.e. immediately put the throttle back where you had it before making the mistake. Dipping the clutch if you have 3 pedals works too. Both of these need to be done before the yaw angle gets too far. You also need to be right on the ball with your corrective steering and unwinding thereof. Many people catch the first yaw but are too slow to unwind it as the back end comes back in again and they swing the other way through a combination of angular momentum the car builds up and their own steering input encouraging it.
What you need to do is explore what the car can cope with gradually. Open the throttle a little bit more each time you leave a roundabout in various conditions and you'll learn what the car can do. Just going straight for full throttle is something that only a slow car lets you away with.
Edited by jamieduff1981 on Wednesday 3rd February 20:38
Vyse said:
Yes the start of the incident was exactly like this. I turned into it and the back end swung the other way, repeated the other way and then stopped.Gassing Station | General Gassing | Top of Page | What's New | My Stuff