RonCT

That's the basis for my liability question. Car has safety feature, driver / instructor disables safety feature, car gets into accident, attorney / engineer demonstrates accident would have been avoided if safety feature was "on"... The problem here is PSM currently can be turned on or off - conscious decision. I can see a day coming when we won't have a choice and it will be hard-wired in just like ABS or airbags. I just think having an instructor mandate you turn it off is asking for trouble in a bunch of ways...

angelo1404

OK

I had my last DE last Saturday. I am in the Novice group of my club. I have run 8 DEs. I am now soloing on this particular track, and have been for the last three DEs. I usually run with PSM on, PASM on, Sport suspension setting on. No unusual problems. I have never spun or had any on track incidents.

So,

On my third 25 minute session, my brake pad failure warning light pops up at the end of the session. I was running with PSM, Sport suspension, but not the PASM.

A visual inspection revealed that the rear pads were badly worn, but the fronts were fine.

What's the verdict?

I am also going to start a new thread.

Yargk

I agree with your disagreement. I'm still a relative novice, but my first time on track was in the 930 when I was a teenager. There's no psm, it's not necessary to learn safely, it's just another net that might help.

RonCT

First off, there's no such thing as PASM off. PASM is the setting of the shocks - either normal or sport. PASM has no effect on brakes as far as I can tell. PSM can impact brakes if you're seriously moving around at the tail - it will use the ABS to slow down any of the 4 wheels (or a series of them) to get the car straight again. But having driving the S for 1.5 years in the most advanced group, I can tell you that you have to really mess up to have PSM even come into play. I spent a few DE's just trying to see where the car's limits are, trying to swing the tail out and make the car dance, and even then, PSM didn't get invovled. Also, there's just so much grip at the rear, I can't imagine that you are getting so much rear wheel spin that PSM is trying to slow down the rear wheels and thus wearing out your pads. Now, here's a question - any chance you drive aggressively on the street and leave some rubber on the pavement? If so and if you don't turn PSM off, you'll definitely cook your brakes because PSM will try to stop rear wheel spin. I'd have to guess that losing your rear pads at the track has nothing to do with the track driving because if you used that much rear brake (via PSM or otherwise), you'd have seriously glazed rotors and you aren't reporting anything odd about rotors. Talk to your shop - maybe they can figure it out.

DrJupeman

This has to be one of the most ridiculous things I've seen posted on RL and I've read a lot of the political threads in Off Topic!

YOU are driving the car, my friend. YOU are ultimately in control.

Just to recap: in your first solo event you spun twice from lifting and you blame the tires and lack of PSM...

I'm sad to read about the mandatory PSM on rules and whatnot. That wreaks of liability concerns, not education concerns, but such is the state of modern sue-happy, take no responsibility for one's actions, times. As an instructor, I don't care if you have PSM on or off. I will teach you the same way and won't rely on you having PSM for my instructing any more than you should as a driver. Any instructor that insists the student leaves PSM on probably shouldn't ever instruct in a non-PSM car. Perhaps we're creating a generation of technology-dependent instructors, not just drivers....

For those of you who have only driven late PSM models, be careful with your assumptions as the earlier PSM cars are noticeably intrusive.

F350Lawman

PSM, ABS, A/C, power steering, ETC are all nice things my car doesn't have...therefore those things are unecessary and for pu$$ies$

MikeBat

For a recently signed off novice like myself, in the rain, I would appreciate PSM.

Otherwise, so far, so good.

rlm328

I started off driving my Cayman which has all of the safety add ons like PSM, and ABS. The PASM allows you to remap your engine and adjust your suspension. With the newer generation cars developing the HP that they are developing a novice driver really needs these safety nets to help keep these cars out of the ditch. I have since "progressed" to a car with no PSM or ABS, and the suspesion is always stiff. I believe that the safety devices let me learn what my short comings were so that I could learn without placing myself or the people on the track with me in an uncontrolled position.

As far as brake wear on the original post, that should have been caught in the pre-event inspection.

Noel

I am a firm believer that PSM, ABS, etc, are nice safety items for daily drivers, but they do tend slow the learning curve on the track. Granted, I have driven my old 911SC for 7 seasons and an old 300ZX for 2 seasons before that, plus autocrossed for a couple years before that in non-PSM/non-ABS cars. I very quickly learned to slide around and to be very smooth, especially in the rain, because, I was my own PSM. I always see a lot of PSM/ABS cars in the rain being driven very slowly (Relatively speaking) and I wonder how much experience they have had with the PSM off and being comfortable really being over and back on the edge with just them (not the car) as the PSM. This is true Drivers' Ed IMO. However, PCA will never tell anyone to turn it off now for liability reasons.

So IMO, PSM does slow the learning IMO, but it really does depend on the student. Those that just want to go fast won't learn as much as those that want to learn to drive. Those that just want to go fast also tend to be the ones that jump to R Compound tires the fastest from what I have seen.

facelvega

I have a well documented off-track excursion from my first lap with PSM off. I started track driving last year in DE’s, and have done 9 DE’s. I am driving a 2007 Cayman S on street tires. Prior to this video, I have driven about 300 laps at TWS, about 150 clockwise. This was my FIRST lap with PSM off, the fourth turn (T12 – high speed sweeper). I did not alter my driving style or speed because PSM was off:

VIDEO


No real damage done. A big thank you goes to the TWS track design, and TWS management for eliminating (as much as possible) thing to run into, and the great PCA instructors (“in a spin – both feet in” – I actually said that out loud while we were going backwards). Looking at what happened, I first looked at driving line. Some comparative driving lines:

- Black: instructor (Red Group) / Cayman S / track tires / 1:59
- Green: advanced (White Group) / Cayman S / track tires / 2:05
- Red: Me, PSM on / Cayman S / street tires / 2:03
- Blue: Me, PSM off / Cayman S / street tires / off




I did not see a smoking gun on driving line, so I looked at steering inputs and accelerator pedal position, running the video in slow motion, and with the data graph:




I feel pretty confident that the slide was assisted by not unwinding the wheel fully before power application. I think the PRIMARY cause was abrupt throttle increase, rather than easing on the gas. And of course, my doom was sealed by coming off-throttle after the drift started.

I think that PSM is a great teaching aid initially, giving confidence, allowing familiarity with higher speeds. I waited to turn it off until I felt very comfortable with the car, and THOUGHT I was turning laps with no help from PSM (no lights coming on).

PSM makes BIG interventions that are obvious (like cutting off the gas). I was not seeing this anymore, so I thought I was catching the car when it started to drift. I now think that either PSM was catching the car (with small, quick inputs on throttle and brake) or at least helping me catch it. I did not develop good enough feel for car position, or good enough habits on smooth steering inputs or smooth accelerator pedal application. I also think that perhaps I developed the (bad) habit of lifting when a slide starts (instinct level), then getting back on the gas (thinking level). In the tiny interval in between, I think PSM was keeping me in shape enough to recover the car. In this case, without the help from PSM, the car was too far gone, so I never got back on the gas.

Conclusions:

PSM is a good beginner’s tool (exactly like training wheels on a bike).

To develop a good feel for the car, and how to recover it, you have to turn PSM off.

When you turn PSM off, dial back to about 70% speed level, and go back up slowly.

When learning your car with PSM off, choose some turns with good run-off areas to test the limits, rather than pushing every single turn. Concrete is very hard.

Areas for further experimentation:
I plan to add lines to capture throttle position and PSM signals to the DME. I think that PSM may be intervening quickly in some cases without lighting up the dash icon. I am also curious to see if PSM will hold throttle when you lift in a curve. I think that I can compare pedal position and throttle position when you lift going in a straight line, and then record it when lifting while circling a skid pad at maximum speed. If PSM “filters” your pedal input both when lifting and when mashing the pedal, it would really slow down learning smooth pedal work.

RickBetterley

Wow - your instructor insisted that turn PSM off?? That is highly unusual.
With newer students, I usually find that we are in the opposite situation - student wants to turn it off, I want it left on.
I'm still shaking my head.

Coochas

At PSDS, the 997s have PSM on and cannot be disabled by the occupant.
PSDS preaches that if you are driving the car properly on the track, that the PSM will not engage.
I've been out for hot laps with most of the instructors including Hurley Haywood. Needless to say, Hurley drives around Barber muy muy rapido and never triggers PSM. This proves the theory that if you're smooth that PSM will not intervene.

Now, after saying all that,...I am happy that I am progressing my driving skills now with a 986. I feel much more in touch with what the car is doing and I know that I have to drive knowing that the ECU will not save me.

I think unless you're at Black or Instructing levels, you should probably leave PSM on. Even then, if you're smooth it won't interfere.

Bull

Another "oldie thread". We are creating a generation of really good bike riders with training wheels!

onefastviking

+1

I find it funny that it wasn't that long ago that PSM didn't exist, isn't technology great to have. Now we have a button to blame when we have an accident at a speed that we didn't have the talent to drive at !
IMHO, the purpose of "track" driving is to learn how to drive, learning the vehicle dynamics (weight transfer, car control,etc.) is key in this, and learning at slower speeds with PSM off is a much easier,gentler, way to learn it.

I personally will drive with PSM off, as an instructor, it is the students choice, although I do explain what and why I drive with PSM off when instructing.

RonCT

Oh no, not this old thread... E46M3, 964, 997.1S, 997GT3, or 997.2S -- no matter whether my car had/has DSC or PSM, or not (ie: 964 and GT3). For those cars that had it, it never came on because I'm driving the car properly. Been through it all - oil, coolant, cone thrown in my line from the car in front, bird strike, etc. - evasive maneuver / correction and back on the gas.

What I don't understand is all the passion about "real drivers don't need PSM". It's just a part of the cars today, just like ABS, larger brakes, disc vs. drum, bigger engines, better steering, etc. If all we wanted was a "pure" experience, I guess we'd all be driving 40 year old cars on the track. But no, we accept and embrace technology and one example is PSM. When the skill level is high enough, no issue. But I'd think when instructing (volunteering), you'd want a low skill level driver to leave it on as a safety margin unless you really know the driver.