To PSM or Not to PSM..That is the question.

When I drive in warm/dry weather, I generally turn the PSM on my 996 off (my Boxster doesn't have it). What do you guys do??

Even with a really FAST drive on the track at Daytona with it on it didn't activate, perfectly tuned.

The system will allow some "slip" in the corners, however it pulls the plug on throttle induced wheelspin right away. Probably not an issue on a C4, but I can get wheelspin in 2nd on hard acceleration and it's not much fun when the PSM kicks in and cuts power.

I always leave it on when driving on public roads.

Always on

I've never even noticed it kicking in - does the PSM light come on when it's active?

Yes light on dash comes on when it's activated The system is very minimally intrusive (unlike BMW's) and I leave it on for street driving. Turn it off on the track only

On. You never know when some unplanned evasive maneuver will be needed, tire blow, tapped at one end by another car, etc.

I felt it kick in yesterday for the first time - as I was zooming through a sweeping right turn at autocross with an instructor yelling "faster, dammit!" (Yeah, just like the wife, but this guy buys the beers afterward)

Even if you turn it "off" it isn't really off. It will kick in although at a higher threshold. I leave it in the off position on the track and can not think of any reason to leave it off on the street. It will save you just when you least expect it.

Not true. If you turn it "off" it is totally off, unless the ABS activates during braking. If you brake hard enough for the ABS to activate the system will turn "on" again.

Well I will stand corrected if you are sure. I was in turn 1 at Watkins Glen with it off and it definately came on in the turn. It is possible the ABS activated in the braking zone, not sure, but I can tell you the psm off light remained lit i.e. I did not have to turn PSM off again. What happens when the PSM kicks back on after ABS? Do you have to turn if off again?

The PSM light will flash. Also on my car I have noticed that is reduces the volume on the radio when it engages. I have had some fun probing the limits of the system in several empty parking lots. I just find it a little obtrusive so I often turn it off. I have not tried the system at a DE yet. However, I already know it would drive me nuts at an autocross.

Yes, if it re-activates you need to turn it off again.

Wow only 20% (of those that have PSM) turn it off. Guess I'm in the minority.

There is NO reason to have PSM on C4S. It simply does NOT have the torque to overpower the all-wheel drive system on the dry.

Further in the minority. It took me a while to find a high option car without PSM. Why look for something you just turn off everytime you get in and drive? Best guess is most don't know how to drive at the limits or don't want to go as fast as the car can go and hence don't need to turn it off. Don't need to argue on this one. There are substantually greater numbers of Green and Blue students than Yellow or White. This is one of those determining factors. You will quickly tell by the comments here as to who fits in what group. Yellow students who are looking to move to White are taught the only way to go faster once you've mastered drving at the limit, is to control exceeding it. This means less braking and losing traction at turn-in. Turning into the inside of the turn to compensate for the drift and carrying the speed. PSM will NOT allow a car to be controlled in this matter. It will activate individual brakes, shut off the throttle and slow the car. If you are lucky, you will be able to keep the car on the track coming out of the corner slowly. Most likely since you turned in to the inside of the track, you will be going off on the inside. Remember that PSM is a safety net for less capable drivers designed to compensate for losing traction, not anticipating that you would drive in this fashion. So it is addequate for most of the drivers out there. Walter Rohrl is 6-7 seconds slower(Carrera, Cayman and Boxster) depending on the model with it on that with it off. EVO and Car & Driver magazines also both verified this when they did wet and dry tests with PSM on and off. PSM off is always faster in the hands of a capable driver, even in the wet, and hence why is wasn't even an option on a GT2 or GT3 which were intended for higher levels of drivers.

Mine NEVER comes on.... oh wait... I don't have PSM.... well, I guess my statement was true.

02 Carrera - is fully right! As we got some snow here in NOVA yesterday, I took my X3 and went to an empty parking lot to train exactly what "02 Carrera" described - going around turns with and w/o DSC. With the system on, I was able to loose traction on the rear axle but couldn't trottle steer the car out of the turn as DSC took all the power away. Turning DSC off made me much faster and able to steer with the trottle. OK on snow you can try this with 20 mph but on dry or wet surface you'll be much faster at the point when you loose the back end, so for less experienced drivers, PSM is a good safety feature as most have just a lack of extreme situation handling experience and intentionally everyone takes the foot from the trottle or even breaks when the back end looses traction which makes the 996 a monster. However, if you go against the instinct and train to apply trottle, then it's fun and makes you fast, but this needs quite some training. So I got cautious on the street and aggressive on the track when I've room for mistakes with my 996 as I have no PSM and learn it the hard way.

Not to disagree with you, but I don't get it. The C4S doesn't have any more power than a C2, it's just split up differently. If PSM can overcome the power of a C2, then I would think it could handle the power of a C4S. What am I missing????

I've read that before but never experienced it. When driving on the track, I disengage PSM and frequently engage ABS and have never had to disengage the PSM again until I re-start the car. Is my car defective?

Hmmm, I don't know. I am headed out right now in my car and there is plenty of snow outside. I'll perform a little parking lot test and let you know what my car does.

Wait until you hit a patch of wet leaves coming around a corner headed down a steep incline. ( The only time I recall PSM coming on while driving on the street, but it very well may have saved my @$$ - PSM = Please Save Me !!! ) BTW Walter Rohrl insisted the CGT have traction control after he drove it w/out it.

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It's too much trouble remembering to turn it off every time I get in the car. When on, it is a pain in the *** when shifting quickly to 2nd gear under hard acceleration.

Here's what I discovered. I was wrong that the system needs to be turned off again after being automatically re-activated. In the "parking lot" my PSM "woke up" (after being turned off) if I applied the brakes while sliding. It went back into standby when I let off the brakes. I found an article on PSM operation and the author describes the PSM operation as follows; However, if you require more fun, you can turn the PSM off. When you "turn it off," you are taking only the outputs offline. The PSM system is still collecting data from the ABS system, the yaw sensor, the lateral acceleration sensors and the steering wheel position sensor. If you have PSM off, and the levels of slip are exceeded, and you do not touch the brakes, the car will continue to slide. If you have not exceeded the levels of slip allowed, and apply the brakes (no matter how hard), PSM will not active its outputs. However, if you have exceeded the levels, AND apply the brakes (no matter how hard), PSM will activate until the car has regained control or you get off the brakes, at which point PSM stops outputting. PSM assumes that since you hit the brakes that you are not comfortable with the level of sliding and that you want it to help. This answers the question, posed by Mike Furnish on the PCASD forum, that inspired this article, "what happens in a spin when you put both feet in?" Presuming that you put in the correct two pedals, PSM will activate.

Anyone ever watch this: Best Motoring International Vol. 3 - Porsche 996 Turbo, The King They do a test with and without the PSM, its about a second faster with PSM on. Its a good video and you should really check it out. They do 0-60, track runs against a Modena, NSX etc, cool video. PS PSM is a definite must in the snow, without it, your back end swings like the ladies with booty!

Best Motoring is the WWF of car testing (i.e. the winners are picked in advance). I agree that PSM works well in the snow, however the car is very controlable without it (with snow tires). From the magazine tests that I have read, most professional drivers are quicker with PSM off. However, I suspect that most amateurs would be quicker with it on.

Don't have it because you can't turn it off and KEEP it off. That is not the way it should be on a performance car. Having said that I would love to have it for daily driving as a safety net.

Not sure what you're confused about. If you are on DRY pavement, the ALL-WHEEL Drive system is enough to keep you from losing your rear-end in VERY spirited driving. This has been MY experience. I'm sure anyone who drives a C4S will agree, it's very easy to keep the rear-end in-place. When the rear-wheels lose traction, the fronts kick-in and help you from "losing it". If you have good tires, the same is the case in the wet. I have NEVER had ANY problem and I ALWAYS hit the button to turn it off. Even when I TRY to kick-out the rear end, I can ALWAYS control it. Now, you add all the torque of the turbo and PSM will come in handy, in the wet.

YES! and you add an all-wheel-drive system and this could not be TRUER! I will never be driving my car in the snow, so that doesn't apply to me. Although if you are planning to drive in the snow, PSM is a MUST-HAVE!!!

I don't get what you're saying man...? I never said that the PSM can overcome the power of anything. I was talking about the car doesn't have the torque. If it had 400 lb-ft or more, it would be a lot easier to lose control. With only 270+ lb-ft, the all-wheel drive system manages control of the car, especially on the dry.

As some of you like to quote my fellow countryman the Austrian Walter Rohrl, let me quote what he said when there was this story about the some early Audi TTs that crashed because of a missing rear spoiler and the missing standard ESP: "When someone back in the 70s and 80s crashed his car, people said: hey can't you drive? If the same thing happens in the 90s, then people say: this damn manufacturer, they made the car unsafe." So recall that what ever happens, the driver controls the car and not the electronic.

Ah, now I get it.

LiveNupe, that is the best cornering attitude through a turn I've seen with a 996 (your avatar). Good work! '04 40th Annie eh? Sounds rich $

Thanx

PSM = "please save me" = too funny!

I drive with PSM turned on. One can never predict when you will lose traction and none of us are good enough to save every loose situation. So what if PSM corrects wheel spin. Why are you doing that on the street? What would happen if you had PSM turned off and spun into a car or bystander? Leave that kind of driving for the autocross or track. BTW, the only place I found PSM to be intrusive was the autocross. I left it on when I ran my car on the track, using it as a guide to smooth out my driving. I'm a bit opinionated regarding PSM and other safety devices when it pertains to street use. We aren't the only ones on the road.

I don't have PSM but have traction control (with LSD) on my 99. Since I haven't had the car for that long, I tend to keep in on when driving on public roads. In autocross, that is a different situation. I found the TC kicked in pretty quickly autocrossing and I was around 2 seconds faster without it (on quick 47-50 second course). Of course, I did spin the car a couple of times "finding" the limit of adhesion. Not sure what I'll do when I take it to my first DE. I suppose, I'll drive with it on and see how I feel. If I feel good, then I'll turn it off, if not, I'll error on the side of caution. Pete