PSM - What's it like when it runs out of skill?
Discussion
I realise that we are talking about potentially expensive holes in the scenery, but I've been starting to get used the car have been "enjoying it" in a monumental way.
I've felt the PSM come in a few times and its quite unobtrusive. The only way I could feel it is because its reactions are clearly digital rather than analogue.
My question is... When you do reach the end of its skill levels, does it suddenly give up, get really confused or just keeping on doing its best (whilst calling you names on the tacho display)?
Either way, its very, very impressive.
I've felt the PSM come in a few times and its quite unobtrusive. The only way I could feel it is because its reactions are clearly digital rather than analogue.
My question is... When you do reach the end of its skill levels, does it suddenly give up, get really confused or just keeping on doing its best (whilst calling you names on the tacho display)?
Either way, its very, very impressive.
PSM does its best, assuming there is any grip left in the tyres. I would not rely on it to get me out of trouble - better to understand why it is intervening in the first place!
Suggest you take the car to a nice big play area - do a day with Don Palmer at Bruntingthorpe and find out what happens when the car really lets go
Suggest you take the car to a nice big play area - do a day with Don Palmer at Bruntingthorpe and find out what happens when the car really lets go
Thanks Will. I've got over 5000 miles track hard miles under my belt (Craner at 125mph 
) and have had some quicker, albeit far less desirable, cars.
I thought I had found its limits, but its just kept sorting things out. The places in question were very open as I have only had the car this weekend.
I remain very impressed.
I would love to do a track in it, on a set of Cups, but my missus would withold marrital rights if I took this on a circuit.
) and have had some quicker, albeit far less desirable, cars. I thought I had found its limits, but its just kept sorting things out. The places in question were very open as I have only had the car this weekend.
I remain very impressed.
I would love to do a track in it, on a set of Cups, but my missus would withold marrital rights if I took this on a circuit.
To get PSM to run out of skill you would need to put the car into the corner waaaay, waaaay too fast and instead of braking, just yank the wheel round and hope.
At which point you will fly off the track and into the tyre wall.
Given that you approach the "limit" gradually, as you would with any other car, PSM will simply step in and inform you tried too hard.
You will, of course, lose loads of speed and have a crap lap time. If you want a quick lap you will need to do it without the PSM light coming on.
There again...its nice that the car stayed on the black bit.
Wonderful system. You'd have to really try to screw it up IMO to actually come off with it switched on. Anybody who does really, really made a BIG boo boo.
At which point you will fly off the track and into the tyre wall.
Given that you approach the "limit" gradually, as you would with any other car, PSM will simply step in and inform you tried too hard.
You will, of course, lose loads of speed and have a crap lap time. If you want a quick lap you will need to do it without the PSM light coming on.
There again...its nice that the car stayed on the black bit.
Wonderful system. You'd have to really try to screw it up IMO to actually come off with it switched on. Anybody who does really, really made a BIG boo boo.
Don said:
To get PSM to run out of skill you would need to put the car into the corner waaaay, waaaay too fast and instead of braking, just yank the wheel round and hope.
Wonderful system. You'd have to really try to screw it up IMO to actually come off with it switched on. Anybody who does really, really made a BIG boo boo.
Don - You must have seen me ???
I Lost grip under braking in a straight line !!. All too quick and no space for the PSM to do much about it. if there is no grip even in a straight line your in the doo doo. http://pistonheads.com/gassing/topic.asp?t=170840
For the vast majority of drivers PSM can and will stop you having accidents, or even "moments" in your car. I agree that it shouldn't be a replacement for driver skill, but it certainly can be a very effective safety device for even the most able. Maybe it is a better driver who admits that regardless of how good they are, there are situations where PSM can supplement their experience and abilities.
As people will quite rightly say PSM cannot provide more grip than is physically available, but what it can do is make more of that grip accessible to the vehicle - that is an important concept to understand. However if you drive your car into a situation where no combination of control inputs to the car could avoid a crash, then PSM cannot do anything for you at all (except flash a yellow light at you while you crash).
PSM should be regarded along the lines of ABS and airbags - it is a safety feature only. It is not performance enhancing like better tyres etc, and if you treat it as such then you should expect to crash.
My professional life revolves around building automation and control systems in a similar vein (although more for things which fly) and I can assure you that no human can do what PSM can, but on the flipside, PSM is NOT superhuman!
I also understand the need to be able to switch it off for being on track etc. Going very fast in these circumstances requires a blurring of the lines of control - something PSM does not like and will not be compatible with, hence why I emphasis PSM is about safety and not about performance.
As people will quite rightly say PSM cannot provide more grip than is physically available, but what it can do is make more of that grip accessible to the vehicle - that is an important concept to understand. However if you drive your car into a situation where no combination of control inputs to the car could avoid a crash, then PSM cannot do anything for you at all (except flash a yellow light at you while you crash).
PSM should be regarded along the lines of ABS and airbags - it is a safety feature only. It is not performance enhancing like better tyres etc, and if you treat it as such then you should expect to crash.
My professional life revolves around building automation and control systems in a similar vein (although more for things which fly) and I can assure you that no human can do what PSM can, but on the flipside, PSM is NOT superhuman!
I also understand the need to be able to switch it off for being on track etc. Going very fast in these circumstances requires a blurring of the lines of control - something PSM does not like and will not be compatible with, hence why I emphasis PSM is about safety and not about performance.
steve rance said:
Providing the driver isn't taking the car beyond his own capabilities and relying on PSM to sort out his ineptitude.
Steve R
Couldn't agree more. PSM will help a driver who understands his own limitations and those of the car deal with the consequences of pushing the performance envelope just a little too far. Given one is approaching the "limit" gradually this is damn useful (to me - an amateur) on track.
If you drive like an a**e there's nothing it can do to prevent you stuffing it.
And it absolutely will not help you get a good lap time. If its had to step in you are already losing time.
On the road its similar. What's great about the system is that if you make a minor error in judgement with respect to the road surface and the grip available it can help you avoid major consequences. If you make a major error then it may help to reduce the consequences but you are still going to an expensive visit to the scenery.
I think I witnessed what PSM is like yesterday. Driving along an NSL and a woman careers out from between some garages and puts the nose of her car in my carriageway. I had no choice but to swerve violently left. The car just remained flat, I heard a tyre chirrup somewhere and the manouver was completed with the minimum of fuss and bother. Very impressive as a safety aid 
Its most impressive feature that I have discovered is its one side braking. Throw the car into a roundabout at a speed that it will want to run wide/slide under and the car applies the brakes to both right hand wheels, tucking the front in, keeping the back in check and holding a very neat line that seems to defy physics.
That is something that you can't do as a driver.
The rest (keeping the tail under control/not getting into understeer), I'm reasonably happy with on my own.
The reassurance come with it being able to react to an end swapping introduction of surface change (by applying braking to the outside rear wheel alone), far quicker than I could. Then again, I am 42
That is something that you can't do as a driver.
The rest (keeping the tail under control/not getting into understeer), I'm reasonably happy with on my own.
The reassurance come with it being able to react to an end swapping introduction of surface change (by applying braking to the outside rear wheel alone), far quicker than I could. Then again, I am 42
Gassing Station | Porsche General | Top of Page | What's New | My Stuff