I'm looking at 2002-2004 C2's and notice that many of them don't come with PSM. How important is it to have PSM? Who benefits the most out of it (track drivers, bad weather, etc)?

I keep reading on the web that it's a replacement for a LSD - which would make it pretty important?

Thanks,
Ben

 

PSM is Porsche Stability Management - it has nothing to do with LSD (Limited Slip Differential). Porsche's version of stability management is not very intrusive at all. It will usually come on just a little after the point where there is no way you could recover from whatever mess you have gotten yourself into. It is safety equipment and it is totally up to you if you think it is worth the money. Most luxury vehicles (and many non-luxury) now come standard with some form of stability management/control. I am very happy to have it in my car, but I have a turbo, so things can get out of control quickly if you are not paying attention. If you have any question about the validity, look for the Top Gear episode on the 2001 911 turbo.

 

See Slider's comments about PSM being different form LSD. I ordered my 2000 996 C2 with PSM and I swear by it! I have had my car on the track a few times and the PSM is fantastic for an amateur track driver like me (Blue run group). More importantly, PSM has intervened and saved my butt several times in street driving and in bad weather driving. I totalled my 97 Boxster without PSM in 99 and now will never get another Porsche without PSM. My 2 cents...

 

I have owned a number of P-cars and I wouldn't look to purchase another without it. It save my a@@ big time in my Boxster S when I hit some sand. I haven't had it come on in the 996, but I also respect the extra power and torque I now have.
It’s hard to explain what it does but when it kicks in, you were about to have an experience.
I think once I track the 996 I'll play and toss the a@@ end out where I have lots of room.

 

Thanks for all of the comments guys.

So here's where my confusion comes in. The C2 / C4 / TT don't have a true mechanical LSD, correct? My understanding is that ASR (Anti Slip Regulation) brakes one wheel if it detects slipping, sending the power to the other wheel (expected with an open diff). Note, I'm not talking about corning here, only straight line acceleration where you'd get uneven wheel spin.

Now, maybe I'm confused here. Is ASR part of PSM, or does it come standard even if the car doesn't have PSM?

I agree, I'd like to find a C2 with PSM - but it just seems like many cars don't come equipped with it.

Thanks, Ben

 

It works great with all the stock suspension and wheels. It feels weird when it kicks in esp when it hits the brakes on just one wheel and gives you an ABS feed back in the brake pedal. It will save you from swapping ends most of the time. When you start to change suspension/wheel/tire components, it can get a bit more intrusive. Never the less I usually leave mine on unless I know the road very well.

 

If you're looking at tracking it often you should find a P with LSD, not that common but they're out there.

If just doing a track day here and there most P's are more capable then the driver so you'll be fine and have lots of fun with it.

Cheers,

Sid.

Ps. do a search in the 997/996 turbo/GT2 section there was an interesting thread on just this subject.

 

http://en.wikipedia.org/wiki/Porsche_911

"Starting from the models with water-cooled engines, 911 Carreras do not come with rear limited-slip differential, except the 40th Anniversary 911, GT2, GT3 and Turbo."

 

I don't have it in my '99 and i never miss it. With the engine in the rear, you'd have to do something pretty crazy to lose it in a non-turbo. The car is 3000lbs and it's mostly sitting over the rear wheels. If you do something like floor it in 1st or 2nd around a turn, then yes, you'll lose it. Idk if PSM will save you from your ignorance at that point or not. I got lose in it once around a turn, with rear engine/RWD stay on the gas it's difficult to spin, period. Again, I don't ever wish I had it.

 

If you never had it - how could you miss it???

PSM is not there to save you from gunning it in first or second gear!!! PSM is there for the same reason that all performance cars from Porsche to Ferrari to McLaren have some form of stability management in today's cars - it is there to allow most drivers to go faster on the track, and in street driving, to avoid losing control in emegency maneuvers. There is no doubt about the effectiveness of PSM whether you are driving a rear engined car or mid-engined car, all the manufacturers will not pour money into developing ever more effective stability control systems. PSM works exceptionally well even for experienced (and non-experienced) drivers.

In a rear engined car, the concept of "you'd have to do something pretty crazy to lose it in a non-turbo" is simply false. Anyone who has been on a Porsche club DE (driver education) will attest to that. See post #4.

Now, if you NEVER take your car to the track and NEVER go 1 MPH above the speedlimit and you ALWAYS keep more than adequate distance between you and the car in front of you, then you may never find PSM useful. But it is still a great option to have in Porsches for bad weather and poor driving conditions.

 

Correct me if i'm wrong,But don't all 99's have LSD?

 

It's like all other ESP systems. If you drive in a manner that causes the ESP/PSM to kick in, you're probably driving out of control so it might help you. I have one in one car and not in the other and never activate it.

 

I look at it as an interesting tool amongst several different tools at your disposal. I had a C2 without and turned it around in the rain on several occasions in the first few weeks I owned it. I had come from a Boxster manual that driven harder in the same circumstances would have been fine. PSM is very handy for the engine out the back, but so are good quality tires, suspension quality and setup, and of course the driver (I wasn't driving it well, obviously). The C2 I had was made dramatically better by moving off Conti rubber and onto S02's. I also left it in Drive in the rain instead of changing gears via the tiptronic in the middle of corners.

PSM is great on my C4S, but its got a hell of a lot of rubber on the ground and has only come on twice since I have owned it, both times in wet parking buildings :-)

 

Get the PSM. You wont notice it until you need it. I was taking a simple left turn, and didn't see the oil slick until it was to late. the car slowed down and saved my ****. For sure I would have slid right into the car next to me, and I wasnt even pushing it at all.

to have fun, just turn it off.......

 

PSM may have saved my life on Wednesday. I was driving at a good clip on the Garden State Parkway, where the posted limit is 65 mph and typical speed is 75+. It's two lanes at this point and the left lane is supposed to be used only for passing. I caught up to a truck in the right lane and pulled left to pass. As soon as I cleared the back of the truck, I saw a deck chair in the middle of the left lane, about 30 feet ahead. I abruptly swerved left in an attempt to avoid the chair (I didn't), swerved right to avoid heading into the woods, and swerved left again to avoid hitting the truck. I'm pretty sure that PSM saved my bacon because that move was way too aggressive for my rate of speed. If I was driving a lesser car, I would probably have been toast.