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Discussion Starter · #1 · (Edited)
I took my new-to-me 06CS to its first DE (with me anyway), and I was less than impressed initially... I only got the car over a month ago with "cheap but new" Yokos on it, which I did not like much on the street but were too new to toss...

Well, they're even worse on the track. First session was crazy, the car would "snake" on me after changing directions, all the more annoying as I think that changing directions is what the Cayman does best. I found out the pressures went up way too high (30-34 became 34-40+), I eventually got those crappy wooden donuts semi-usable by dropping them to 28-30, I know, sounds super low, but once hot (and did they get HOT) it was more manageable...

Session 2, once I stopped sliding around, I got really annoyed at PSM. I have not finished paying for the car so I had planned on leaving it on - a brand new M3 hit turn 1's wall hard and was totalled, good driver too, just said it was greasy out there... Anyway, PSM: Bad idea... The thing would not only cut power at the worse of times, it would sometimes make things worse for me... This was Sebring, maybe some of you know Bishop's bend, it's a gentle but fast kink-straight-kink to the left that you can take as one gentle arc if you hit the first apex right, you don't need to touch a thing: neither gas nor steering (so you cannot accuse me of anything)....the car drifts out and comes back to hit the second apex by itself, it's very nice (except for the wall to your right)...

Friggin' PSM decided it did not like the gentle drift there and I could feel it brake one rear wheel and totally unsettle the car mid kink. Not a nice feeling AT ALL this close to the wall.
Could this be made worse with the bad tires ? I don't know, not sure how PSM gets its data...

Session #3, I grew a set and turned PSM off. Transformed the car. It rotated when I wanted it to, it accelerated when I wanted to, a dream to drive, despite the crappy rubber... No more problems at the aforementioned kink, smooth ! No spins, no scary moments, all in all a much smoother and faster ride ! Go figure !

So one of my questions is: does PSM chill out a little with better tires ? I should point out that I have 10+y track experience with a semi-race prepped aircooled 911 on R rubber, so if I was "that" ham fisted I'd have hit a wall by now. I was not being "unsmooth", or i'd have spun or run wide with it off, yet I ran much better and faster with it off.. Would the aftermarket limited slip differential help any with the conditions triggering PSM ?

On the topic of tires, the 2 fast guys in the CS that day were running michelin cups and Bridgestone RE11. Both said they simply installed the baffled oil sump for $500 and had not had any Kaboom issues. I'm tempted to do the same (fast left turn #1), so that I can upgrade the tires a good bit...

Good day all in all, glad I stuck with it because I was majorly disappointed initially, I know my old 911 would have been faster at first, but probably not so by the end of the day. And I had A/C all the way home ;-) I just need sticky shoes now!
 

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PSM is not a performance device in Porsches, it is a safety device. You can't extract the maximum performance out of your car with PSM on. If you know how to drive (at race pace) then you need to drive with PSM off. Only then you can drift the car and extract the maximum potential out of of it. With better rubber you will be faster at lower slip angles (not inducing psm intervention) but for maximum performance you still want psm off. If the car feels like "on rails" you are not pushing hard enough.

Also, the car is more naturally predictable with psm off, otherwise you are anticipating correctly minor corrections and the system is second guessing against your inputs... Not good. All this talk about psm on being the fastest as psm off is BS and only true at 9/10ths. OK for learning the line at a DE but not really then ultimate possible pace.
 

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+1. I've done 3 track days so far in my gen 2 CS. I can't imagine anyone driving one fast with PSM on. The first time I turned it off on track, I had to ask, "what's all the flashing going on on the dash?" I later learned that's PSM telling you where it WOULD be intervening if it were on.

This car when setup properly is f'ing amazing; neutral, easy to rotate and a joy to drive fast. I'm going to guess you're a victim of crappy tires. I've run the OEM Bridgestones (very good), Hankook V12's (almost as good) and NT01's (yahooo!). If you're going to track regularly, I can't recommend a spare set of NT01's strongly enough. Just add a set of GT3 lower control arms and an alignment and you will be simply amazed.
 

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Like you found, if I drive at the track with PSM on and no sport mode, its pretty hopeless. Fortunatley I have SC, so thus in sport mode it pretty well never comes on if you are driving smooth.
Very generally speaking, you can go slightly faster with PSM off, but if you make a big mistake then you'll be wishing PSM was on.
 

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Like you found, if I drive at the track with PSM on and no sport mode, its pretty hopeless. Fortunatley I have SC, so thus in sport mode it pretty well never comes on if you are driving smooth.
Very generally speaking, you can go slightly faster with PSM off, but if you make a big mistake then you'll be wishing PSM was on.
As an average driver enjoying the DE and learning lots, Sport Chrono and PASM and Michelin PS2 tires make it a very sweet ride. To be sure I'm not pushing 9/10ths, let alone 10/10th but then I give up a few seconds on the track, but I also give up 45 years to the younger drivers with quicker reflexes. I keep PSM on so I can drive home in the same car I brung. My CS is a wonderful, confidence building car for me. IMHO Ed
 

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I leave the PSM on for a wet track/rain, and usually during the first session on a dry track until my tires (and brain ;) ) warm up. I know on the 2 tracks I regularly run on, there are at least 2 turns where having PSM on will slow you down when you start pushing 8-9/10ths . . . I imagine that is true on most other tracks as well.
 

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Discussion Starter · #7 ·
but if you make a big mistake then you'll be wishing PSM was on.
Doesn't it kick back ON in extreme circumstances ?

Thanks for confirming I'm not imagining things... (hard to imagine a blinking light and those gas cutoffs or unwanted brake applications anyway...)
I will do the baffles, and investigate the lower control arms later, not sure I have a budget for all... what's the price on those?
 

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Doesn't it kick back ON in extreme circumstances ?

Thanks for confirming I'm not imagining things... (hard to imagine a blinking light and those gas cutoffs or unwanted brake applications anyway...)
Some misconceptions here, IMHO.

PSM is never off. Pushing the PSM button simply raises its limits. Turning on SC raises it higher still.

If the PSM light on the gauge face is on solid, it simply means that you have raised its limits by pushing the PSM button. If it flashes while you are driving, it IS intervening, not telling you what it would be doing if it were on.

And I concur 1000% with everyone that has already said, TURN IT OFF. Although, as I said, it is never really Off.

Brian

EDIT: There is a document kicking around that shows a chart of how PSM is effected depending on the switch settings. I swear it is in the site library somewhere, but my search skills are failing me at the moment.
 

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If you have the right tires, and you're driving well, the PASM in 'sport' mode shouldn't really interfere with your driving at all. At worst you may feel it on occasion, but again if you're driving well and your car is set up properly, this is one of the best stability systems around. You can drift the car very nicely with PASM in sport mode. I do agree that to maximize the last few tenths, and to really understand what your car is doing you have to turn it off.

HOWEVER - use it whenever you think you need it, especially if you're driving in the rain on a tricky track. I drove with one of the Porsche factory drivers in one of the new Spyders around Mid-Ohio on a mildly wet track and he put the PSM on in sport mode - so you'll be in good company.

The BMW system on the other hand just sucks. You really can't get any kind of decent performance with the bimmer system on, and you have to shut it off if you're any kind of decent driver.
 

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I'm an experienced driver running R comp tires and I normally run PSM on in SC Sport mode. I run a lot at NJMP and I've noticed PSM intervention at Lightning turn 5 and Thunderbolt turn 2. In both instances the apex is on a crest of a hill. Last week I got frustrated and turned PSM off. I managed to spin the car twice, both times in slow turns. In both instances I felt the car was a a little loose and thought I had made the required corrections. Just when I thought it was settled down, I got snap over-steer. My car is set-up very neutral, maybe I should dial in a little understeer. Till I sort this out, I'm leaving PSM ON.
 

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Deschod,
My experience with my wife's '07 CS has been identical, even on R compounds and with race pads. I can't drive the car on the track with any speed with PSM on. It intervenes way too much and at the wrong time and feels very unpredictable and unsettling. I have been tracking a '95 M3 for 14 years and the only electronic nanny it has is ABS. You are used to the same type of car, with minimal electronic "safeties" (and obviously can drive it well!). We expect the car to have a specific response when we give it a certain input. With the CS with PSM on, the computer frequently seems to have different ideas. I have also found the car feels very "vague" in transitions and at turn in with PASM (suspension) on normal and not sport/stiff. I like it best with PSM off, the suspension stiff but sport mode off (otherwise the accellerator pedal is too on/off and becomes difficult to modulate especially in sweepers where the car is just gently drifting and you need to change its attitude with gentle throttle inputs). I leave it soft and PSM on in the rain and on the street.
Tom:cheers:
PS We do have a Quaif diff and lower, slightly stiffer springs.
 

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Deschod,
My experience has been identical, even on R compounds and with race pads. I can't drive the car on the track with any speed with PSM on. It intervenes way too much and at the wrong time and feels very unpredictable and unsettling. I have been tracking a '95 M3 for 14 years and the only electronic nanny it has is ABS. You are used to the same type of car (and obviously can drive it well!). I have also found the car feels very "vague" in transitions and at turn in with PASM (suspension) on normal and not sport. I like it best with the suspension stiff but sport mode off (otherwise the accellerator pedal is too on/off and becomes difficult to modulate especially in sweepers where the car is just gently drifting and you need to change its attitude with gentle throttle inputs). I leave it soft and PSM on in the rain and on the street.
Tom:cheers:
I agree about the throttle mapping in 'sport chrono' mode. Thankfully I don't have sc, and my throttle map doesn't change when I use sport PASM. I found it very difficult to maintain a smooth rpm on heel-toe downshifts and when coming back onto the throttle on turn exits with sport chrono. Maybe just personal preference.
 

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The softronic flash can give you the ability to be in "sport" mode continuously. This is what I use on the track and its much more pleasant.

I think for the majority of folks driving at DEs, they need to leave PSM on. Its a safety device and if you are pushing it hard enough to turn it on, you are likely doing something you shouldn't. If you have 60+ track days and use slicks, this probably doesn't apply to you.


Good time for me to point out I don't have PASM, or sports mode, just bottom of the barrel PSM... All by itself, without the other toys, it's very intrusive...
 

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I'm an experienced driver running R comp tires and I normally run PSM on in SC Sport mode. I run a lot at NJMP and I've noticed PSM intervention at Lightning turn 5 and Thunderbolt turn 2. In both instances the apex is on a crest of a hill. Last week I got frustrated and turned PSM off. I managed to spin the car twice, both times in slow turns. In both instances I felt the car was a a little loose and thought I had made the required corrections. Just when I thought it was settled down, I got snap over-steer. My car is set-up very neutral, maybe I should dial in a little understeer. Till I sort this out, I'm leaving PSM ON.
Just curious how your rear brake pad wear compared to the fronts. At least in newer BMWs that are driven close to the limit with stability control on, the rears will get very hot and actually start to wear quicker than the fronts.
The spins at slow speed may be due partly to previously unrecognised excessive throttle inputs that were moderated by PSM when you had it on, but may also be due to the extreme sensitivity to throttle pedal inputs that Sport mode seems to create making it difficult to modulate the throttle. In newer Porsches, I have typically found that students are usually smoother and ultimately faster with sport mode off for that very reason. (See my note above for my preferred settings in our '07 CS.)
Tom
 

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PSM is not a performance device in Porsches, it is a safety device. You can't extract the maximum performance out of your car with PSM on. If you know how to drive (at race pace) then you need to drive with PSM off. Only then you can drift the car and extract the maximum potential out of of it. With better rubber you will be faster at lower slip angles (not inducing psm intervention) but for maximum performance you still want psm off. If the car feels like "on rails" you are not pushing hard enough.

Also, the car is more naturally predictable with psm off, otherwise you are anticipating correctly minor corrections and the system is second guessing against your inputs... Not good. All this talk about psm on being the fastest as psm off is BS and only true at 9/10ths. OK for learning the line at a DE but not really then ultimate possible pace.
Totally agree!
Tom
 

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Good time for me to point out I don't have PASM, or sports mode, just bottom of the barrel PSM... All by itself, without the other toys, it's very intrusive...
One alternative is to reflash your non SC car with Softronics Software with the sport mode on all the time.

BTW, PASM does not have anything to do with PSM or SC. PASM is just the suspension settings.
 

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One alternative is to reflash your non SC car with Softronics Software with the sport mode on all the time.

BTW, PASM does not have anything to do with PSM or SC. PASM is just the suspension settings.
When you press sport mode on our CS it alters both the throttle responsiveness and goes to the stiffer suspension setting (PASM).
Tom
 
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