Tell me how PSM works...or not
02-23-2006, 03:14 PM
#16
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"Under hard racing conditions, I think a competent driver would be faster without the electronics"...
True, but there are far more Mittys out there than competent drivers. I've had the fortune of a great deal of instruction & seat time, and I'll be the first to admit I can't exceed the limits of PSM....
Sport mode equipped vehicles have "ver 2" (it's not an official title... just an insider shorthand). I should say it as "under proper conditions and in sport mode the limit can go as high as 9 degrees" - as you know, it's not an absolute figure.
Agreed on the Ferrari system. I don't know the software source, but they've obviously spent a great deal of time & effort in good calibration. As far as I know, their algorithm map shows slopes, allowing for smooth adaptation of a variety of thresholds. PSM is a bit more "abrubt" - either a given value is reached or not.....
Of course, this discussion could lead into a "German" vs "Italian" thing....
Hope that makes sense,
JS
True, but there are far more Mittys out there than competent drivers. I've had the fortune of a great deal of instruction & seat time, and I'll be the first to admit I can't exceed the limits of PSM....
Sport mode equipped vehicles have "ver 2" (it's not an official title... just an insider shorthand). I should say it as "under proper conditions and in sport mode the limit can go as high as 9 degrees" - as you know, it's not an absolute figure.
Agreed on the Ferrari system. I don't know the software source, but they've obviously spent a great deal of time & effort in good calibration. As far as I know, their algorithm map shows slopes, allowing for smooth adaptation of a variety of thresholds. PSM is a bit more "abrubt" - either a given value is reached or not.....
Of course, this discussion could lead into a "German" vs "Italian" thing....
Hope that makes sense,
JS
02-23-2006, 03:28 PM
#17
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Originally Posted by Bob Rouleau
... It seems to scale with the setting and goes from nanny (poor traction mode) to 'yee-haaa!' in race mode. ...
Regards,
Regards,
I like yee-haaa mode!
02-23-2006, 07:21 PM
#18
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My own experience with PSM old version on my 2001 Cayman S Cabriolet.
PSM off was only intrusive when the car was out of shape at the track (me overdriving), it was never a problem on autocross. However, I would rather correct the car myself, because the PSM drifts the car out, and there is a huge lag to get the throttle control back.
PSM off was only intrusive when the car was out of shape at the track (me overdriving), it was never a problem on autocross. However, I would rather correct the car myself, because the PSM drifts the car out, and there is a huge lag to get the throttle control back.
02-23-2006, 08:09 PM
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"2001 Cayman S Cabriolet"... well, that's a new one to me.
"because the PSM drifts the car out, and there is a huge lag to get the throttle control back."
An excellent description.
Crank the wheel at speed, and you've created a slip angle. Hold that, you've got push (understeer). PSM may (I repeat MAY - other variables will impact the actual outputs) then allow the rear to "step out", reducing the slip angle, so your experience makes perfect sense.
Of course, the system doesn't "know" about the wall - or cones - to the side, so PSM will not "magically" keep one whole. What it will do is try to stabizile the vehicle in the direction set by the driver...(good luck, eh?)
Frankly, a Boxster w/PSM would not be my first choice in AX.... but neither would a stock Boxster.
J
"because the PSM drifts the car out, and there is a huge lag to get the throttle control back."
An excellent description.
Crank the wheel at speed, and you've created a slip angle. Hold that, you've got push (understeer). PSM may (I repeat MAY - other variables will impact the actual outputs) then allow the rear to "step out", reducing the slip angle, so your experience makes perfect sense.
Of course, the system doesn't "know" about the wall - or cones - to the side, so PSM will not "magically" keep one whole. What it will do is try to stabizile the vehicle in the direction set by the driver...(good luck, eh?)
Frankly, a Boxster w/PSM would not be my first choice in AX.... but neither would a stock Boxster.
J
