PSM Saves the day!
Discussion
Whilst driving my 996TT home from work this evening in a nice relaxed pre xmas manner I went round the same roundabout I use everyday in at a very sensible speed (there was traffic) only to find this time it had a nice thick layer of mud on it!
This sent the back of my car out at about a 45 degree angle but before I even had time to react the PSM light flashed at me and some magical electronics took place!! the next second I was straight back on course with no drama, no time to panic or react just my cars way of saying 'don't worry I've got this one sorted'.
My point is I just wanted to say what a fantastic car it is like every Porsche I have owned!! and to think last week I was going to sell her after xmas. What was I thinking??
In the time I have had the car the brakes have saved my life when a car pulled out as I could stop in time, the PSM has saved me front ditches and the power has kept me entertained! ahhh what a car!! :-)
This sent the back of my car out at about a 45 degree angle but before I even had time to react the PSM light flashed at me and some magical electronics took place!! the next second I was straight back on course with no drama, no time to panic or react just my cars way of saying 'don't worry I've got this one sorted'.
My point is I just wanted to say what a fantastic car it is like every Porsche I have owned!! and to think last week I was going to sell her after xmas. What was I thinking??
In the time I have had the car the brakes have saved my life when a car pulled out as I could stop in time, the PSM has saved me front ditches and the power has kept me entertained! ahhh what a car!! :-)
OK, here's a REALLY daft question on this topic which I wouldn't normally ask except that I'm at the far end of a bottle of port and have kind of always wondered...
Can PSM apply brakes (to one wheel or more) even if the driver is not pressing the brake pedal? I'm happy that it can vary power via fly-by-wire/e-gas and so on but is there a similar system on the brakes?
Phew, feel better now its out there....
Can PSM apply brakes (to one wheel or more) even if the driver is not pressing the brake pedal? I'm happy that it can vary power via fly-by-wire/e-gas and so on but is there a similar system on the brakes?
Phew, feel better now its out there....
PSM - bloody wonderful.
Interesting question as to whether or not it can apply the brakes without brake pedal pressure - not sure.
A couple of years back I took the Box down a single track lane and ended up needing to put two wheels on a muddy bank in order to let a car past. Pressing the accelerator to move away resulted in an interesting clicking coming from the left rear wheel, the throttle not responding as much as I was pressing the pedal and the PSM light coming on. I pulled away with a small amount of wheel slip...
So maybe it can...
Interesting question as to whether or not it can apply the brakes without brake pedal pressure - not sure.
A couple of years back I took the Box down a single track lane and ended up needing to put two wheels on a muddy bank in order to let a car past. Pressing the accelerator to move away resulted in an interesting clicking coming from the left rear wheel, the throttle not responding as much as I was pressing the pedal and the PSM light coming on. I pulled away with a small amount of wheel slip...
So maybe it can...
LeeME3 said:I think that it can - certainly this from the Porsche website implies that the ABD can apply brakes in oversteer and wheelspin situations where presumably the driver is likely to be on the accelerator rather than brake pedal.
Can PSM apply brakes (to one wheel or more) even if the driver is not pressing the brake pedal? I'm happy that it can vary power via fly-by-wire/e-gas and so on but is there a similar system on the brakes?
Porsche website said:
When the car is in motion, PSM uses a range of sensors to monitor the direction, speed, yaw velocity (speed of rotation around the vertical axis) and lateral acceleration. Based on this information, it can then calculate the actual direction of travel. If the car begins to oversteer or understeer, PSM applies selective braking on individual wheels to bring it back into line. Although it can never suspend the laws of physics, PSM does provide an extra margin of safety whenever you need it most.
If the wheels lock under braking, PSM uses a modified ABS to shorten the braking distance.
If applying the throttle on wet or other low-grip surfaces, PSM uses the integrated ABD (automatic brake differential) and ASR (anti-slip regulation) functions to maintain traction and stability.
>> Edited by jeremyc on Thursday 22 December 09:14
PSM etc can brake each wheel individually as can most of the other manufactures DSC etc. It can also react way faster than any driver can
Brillaint feature that should be standard on all cars, as long as they put in a button to switch it off.
Beats me why they miss it out on the GT3... as long as you can fully switch it off it should be there, so you can drive to/from the tracks with it switched on.
>> Edited by fergy on Thursday 22 December 09:15
Brillaint feature that should be standard on all cars, as long as they put in a button to switch it off.
Beats me why they miss it out on the GT3... as long as you can fully switch it off it should be there, so you can drive to/from the tracks with it switched on.
>> Edited by fergy on Thursday 22 December 09:15
Im sure the psm does apply the brakes to individual wheels when it detects a slide. In my 996 targa at Goodwood a few years back, I had set up the corner, finished the braking and was driving around with a neutral throttle (constant speed) the speed was a bit too high and the car was drifting to the outside but I could not put any more lock/other inputs on the wheel or throttle as it would have spun it/slid the tail out.
As soon as I realised, opps im along for the ride, the inside wheels braked and 'tugged' the car back on line and kept me off the grass. It would not have been a big off but an off nonetheless.
So PSM is very helpful net in small/medium loss of control but cant help if you really overcook it or are completly stupid. Super cars.
As soon as I realised, opps im along for the ride, the inside wheels braked and 'tugged' the car back on line and kept me off the grass. It would not have been a big off but an off nonetheless.
So PSM is very helpful net in small/medium loss of control but cant help if you really overcook it or are completly stupid. Super cars.
...and another potentially daft question....
I've heard it said, but can't remember where (which usually means down the pub!) that when a PSM equipped car goes back to an OPC for service they check that the PSM is running the latest software and, if not, update it. Is this true (in fact for all the on-board software, not just PSM) and if so can the independents do it as well?
I've heard it said, but can't remember where (which usually means down the pub!) that when a PSM equipped car goes back to an OPC for service they check that the PSM is running the latest software and, if not, update it. Is this true (in fact for all the on-board software, not just PSM) and if so can the independents do it as well?
I don't know about PSM, but can vouch for BWM's DSG and Audi's ESP that both will brake individual wheels to keep the car on the road. Spent 15 minutes on a skidpan trying to spin a BMW with DSG - it's ridiculously hard, and the instructor didn't look at all impressed when I managed it.
jeremyc said:
I think that it can - certainly this from the Porsche website implies that the ABD can apply brakes in oversteer and wheelspin situations where presumably the driver is likely to be on the accelerator rather than brake pedal.
Obviously my old crock of a 993 doesn't have this wonderful PSM safety net that you're talking about, but it does have ABD. This only works at low speeds of up to around 45 kph, and essentially uses the brakes to control a spinning wheel, i.e. traction control. So if you're going hammer and tongs at higher speeds in a 993 and you get wheelspin or start powersliding, there ain't nobody goin' to help ya buddy....
Do you think that there may be a negative element to PSM? In the same way that equipping cars with ABS was shown to make drivers drive that bit closer to the limit because they felt that ABS could get them out of the shite - hence they were shown statistically (in Germany) to have less accidents, but much bigger ones once the limitations of the laws of physics had been surpassed. So with PSM, being aware that you have a silicon fairy godmother ready to intervene if you overcook it, will it tend to make you push the limits that bit more?
fergy said:
Brillaint feature that should be standard on all cars, as long as they put in a button to switch it off.
Beats me why they miss it out on the GT3... as long as you can fully switch it off it should be there, so you can drive to/from the tracks with it switched on.
Dunno, but I rather like the knowledge that its up to me to catch things. I reserve the right to edit my opinion if I bend the car
You can't turn PSM off fully either. Not that they couldn't change this, but thats how it stands on current 911s.
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