PSM......On or Off?.......
04-08-2010, 01:29 AM
#31
On. No real reason to turn it off for a DE. It will only kick in when necessary so the feedback is the same - alter the speed or line. One exception, it will seem to kick on without need on tight, off camber corners where there is excessive inside wheel spin.
This does change as the car is set up more agressively, but not much. I can run within a second on a 1:30 lap with PSM on or off. Again, not relevant for a DE.
I still have PSM active in my CaymanSpec racecar and aways run with PSM on for the first lap or two of every session (except qualifying and race). Also, it is outstanding if the track is damp/wet.
Cheers,
This does change as the car is set up more agressively, but not much. I can run within a second on a 1:30 lap with PSM on or off. Again, not relevant for a DE.
I still have PSM active in my CaymanSpec racecar and aways run with PSM on for the first lap or two of every session (except qualifying and race). Also, it is outstanding if the track is damp/wet.
Cheers,
04-08-2010, 09:36 AM
#32
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04-08-2010, 09:47 AM
#33
NASA Racer
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If I had something that could potentially save me from putting my street car into a tire wall after I pulled a bone head move on the track I would not only keep it on, I would create an alter and worship it. Race car - different story.
04-08-2010, 03:00 PM
#34
Mr. Excitement
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Leave it on and see how the car acts. You will figure out if you want it on or not after seeing what it does and does not let you do.
04-08-2010, 04:54 PM
#36
FWIW, for autocross you absolutely have to turn off PSM. I wish there was a way to tune
PSM. There's probably no way to design a PSM that will simultaneously catch street/race
problems before they get too far, and allow the continuous looseness and aggression that
autocross requires. If the course is dry, PSM can cost 1-1.5 seconds in a 45-second course.
PSM will actually completely shut down the throttle for what seems like a full second if you
get appropriately loose in a slalom. It can be like a lawyer tapping you on the shoulder while
you're having sex.
Joe
PSM. There's probably no way to design a PSM that will simultaneously catch street/race
problems before they get too far, and allow the continuous looseness and aggression that
autocross requires. If the course is dry, PSM can cost 1-1.5 seconds in a 45-second course.
PSM will actually completely shut down the throttle for what seems like a full second if you
get appropriately loose in a slalom. It can be like a lawyer tapping you on the shoulder while
you're having sex.
Joe
04-09-2010, 07:45 AM
#40
Moderator
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I think you guys saying PSM is like autopilot or that it wants to straighten the car haven't driven a 987 or 997 on the track. The Porsche literature gives specifics, but I'll tell you from my own experience on the track - modern PSM will let you rotate up to about 22.5 degrees before it will kick in. One example is Watkins Glen last season at about 105 at the top of the Esses where the back end stepped out about 20 degrees and I counter-ed and straightened it out. PSM never kicked on. Even at Lime Rock on Monday, I was "testing" the new setup of my car and was sliding the back end out quite a bit and it never came on. When I got the car I thought maybe PSM wasn't working in the car, but testing that on the street or on a wet track proved it was there. Some how PSM has become so sophisticated that it almost knows what's in your mind.
I think I was the first reply to suggest spend 2 sessions with it on and 2 with it off and you decide.
I think I was the first reply to suggest spend 2 sessions with it on and 2 with it off and you decide.
04-09-2010, 08:21 AM
#41
The Penguin King
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I wonder how many people who are immediately saying turn it off actually have experience with the current generation of PSM. I'm no Shumi, but I'm not a rolling chicane on the track. My comments come from experience with pushing both my 997S and also a Cayman or two fairly hard. As I mentioned, my experience has been that this current generation will give you a fair amount of latitude. I would never recommend turning it off in a street car before first experiencing and analyzing its intervention.
I think you guys saying PSM is like autopilot or that it wants to straighten the car haven't driven a 987 or 997 on the track. The Porsche literature gives specifics, but I'll tell you from my own experience on the track - modern PSM will let you rotate up to about 22.5 degrees before it will kick in. One example is Watkins Glen last season at about 105 at the top of the Esses where the back end stepped out about 20 degrees and I counter-ed and straightened it out. PSM never kicked on. Even at Lime Rock on Monday, I was "testing" the new setup of my car and was sliding the back end out quite a bit and it never came on. When I got the car I thought maybe PSM wasn't working in the car, but testing that on the street or on a wet track proved it was there. Some how PSM has become so sophisticated that it almost knows what's in your mind.
I think I was the first reply to suggest spend 2 sessions with it on and 2 with it off and you decide.
I think I was the first reply to suggest spend 2 sessions with it on and 2 with it off and you decide.
04-09-2010, 08:31 AM
#42
Drifting
Paolo, i saw you drive your race car very competently at NJMP back in the fall of 2009. If i am not mistaken, you podiumed in the enduro.
First, I assume that are you going to the DE to re-acquaint yourself with LRP and not to go drive perfect lines with your street car.
In this case I would first do a couple of laps with the PSM just to see what happens (so you write about it to inform those who are curious) and then turn the system off so you can have fun with your car with street tires. Get to practice throttle steering in big bend and the left hander (without taking the risks associated with walling your car).
See you at the Glen and enjoy Rome with your son while we have fun at the LRP club race.
First, I assume that are you going to the DE to re-acquaint yourself with LRP and not to go drive perfect lines with your street car.
In this case I would first do a couple of laps with the PSM just to see what happens (so you write about it to inform those who are curious) and then turn the system off so you can have fun with your car with street tires. Get to practice throttle steering in big bend and the left hander (without taking the risks associated with walling your car).
See you at the Glen and enjoy Rome with your son while we have fun at the LRP club race.
