has no place in a sport car, you should read what the chief engineer and product manager of Porsche had to say. He was interviewed by EVO magazine and he stated that the sole criteria for improving on Porsche products was Ring times. Each new model should improve the time over the old model.

He also stated that to that the fastest Ring times was achieved with PASM in the normal setting for ALL their cars except for the 997 TT because of the overboost function. When they tried race or no PASM, their times were considerable slower..

Now if Porsche is the expert in sport car performance who are we to disagree with their findings? Can we now put this sucker to bed?

 

Here is what Porsche had to say about PASM. It is an active stability system.

the PASM ensures excellent performance and even greater driving safety in extreme situations.

Operating principles of PASM
PASM selects the required damper hardness for each individual wheel from a precisely co-ordinated map in both the Normal and the Sport programme. The possible damper settings range from comfortable to decidedly sporty. Both programmes, which overlap slightly in some areas, are additionally superimposed with five special software modules to provide the optimum damper settings for every driving condition.

The system automatically selects the appropriate damper hardness based on the PASM programme selected and the driving condition identified.

The Normal programme offers comfortable settings with low damper forces. Special control algorithms in the PASM software modules enable the chassis to offer greater active driving safety in extreme driving situations, even with the Normal programme. To increase driving safety at higher speeds, the dampers are automatically switched to a harder damper setting as speed increases.

The dampers switch to a hard characteristic when Sport mode is activated. This offers superior agility and excellent steering precision on uneven surfaces. If the system detects an uneven driving surface in Sport mode, it immediately switches to a softer characteristic to improve contact with the road surface. PASM selects the optimum damper setting for this softer characteristic from the Sport map.

Since extremely hard damping is not always the ideal solution in every driving situation (depending on the driving surface, the vehicle may start to bounce or shift), the intentional overlap between the Normal and Sport maps allows a noticeably soft setting to be selected if necessary. The customer gets an “active sports chassis” which automatically responds to the actual road surface and switches from a hard, sporty damping setting to a comfortable range as necessary. PASM switches back to the original characteristic as soon as the road surface is smooth enough.

The following is a detailed description of the five software modules overlapping Normal and Sport mode.
Lane-change module
The damper forces at both axles are immediately increased in response to rapid steering movements, for example sudden evasive manoeuvres. This reduces body tilt and instability, thereby significantly improving vehicle control even in extreme situations.

Vertical-control module
In the Normal programme, the damper force is increased as soon as the vertical movement of the body, for example when driving over uneven surfaces, rises over a specific threshold value. This prevents body instability and therefore woolly driving behaviour.
In the Sport programme, the damping is slightly reduced automatically to improve contact between the road and the wheels as body movements increase. This also results in a noticeable increase in comfort.

Lateral-acceleration module
If specific, speed-dependent thresholds for lateral acceleration are exceeded when cornering in the Normal programme, the damper force is increased by different, defined amounts for each side of the vehicle. This prevents vehicle instability and significantly increases driving precision.
In the event of large vertical movements and high lateral acceleration coinciding, the higher of the vertical-control and lateral-acceleration damping values is set. This happens if, for example, the damping in the Sport programme was previously decreased by the vertical-control module.

Brake module
PASM switches to harder damping at the start of a braking operation to reduce vehicle nose-dive when braking. This way, higher brake forces can be transmitted to the road faster. It switches back to a softer setting (this setting is different for the front and rear axle) after a specific amount of time. The result is improved road contact, and thus a shorter braking distance, particularly when braking on uneven surfaces.

Load-change module
The damper characteristics for the front and rear axle are individually switched when accelerating heavily, releasing the throttle or changing lanes. In Normal mode, the dampers are briefly switched to a harder damping setting in these driving conditions. This avoids excessive lifting or diving at the front of the vehicle (“pitching”). In Sport mode, a softer damper characteristic is briefly selected if necessary to improve traction when accelerating, particularly on uneven surfaces.

Components
The PASM system comprises the following components:
• Four dampers with continuously adjustable damping force (each with one bypass valve)
• PASM control module
• Two acceleration sensors for detecting vertical movement of the body (one at the damper dome at the front right and one at the rear left). Further signals such as lateral acceleration, steering angle, travel speed, brake pressure, engine torque, etc. are read in via the CAN bus.
• One button for selecting the programme (Normal or Sport)

The system measures body movements via one acceleration sensor on each axle (front and rear). Values such as lateral acceleration, steering wheel angle, vehicle speed and information on possible braking operations are provided by the PSM via the CAN bus. Engine rpm and torque values are provided by the Motronic via the CAN bus.

 

Are you sleeping yet?

Give it up, Nick , you obviously don't understand the difference between PASM and PSM (as icon politely points out).

Your bias blinds you, distorts your objectivity and undermines your credibility, and you've made yourself the butt of forum jokes from 6Speed to Rennteam.

You must crave attention!

 

Nick the 'ring is very bumpy. With PASM set to FIRM (read really stiff) the car is less stable on the bumps. The best times were set with the suspension in its more supple mode. I admit that Porsche acronyms are confusing, but PASM is an adjustable suspension. My Mercedes has it too, I suspect furnished by Bosch in both cases.

Rgds

 

YAWN......

 

Nice try Nick, but I think we'll all be staying up a bit longer...

 

Empty cans rattle loudest

R+C

 

I have read the description of the PASM several times. Porsche frequently uses the terms safety, stability management and active. Is it different from PSM? Yes, Does it make it less a stability management system. NO! It is a stability management system.

Colm what you term as brunt of jokes, is for the most part fun banter. I do not expect everyone to agree with my negative feeling about Porsche the company on a PorscheChat site. It comes with the territory.

 

I always considered stability control to be some form of yaw control.

This thread needs stability management for yaw-n control...

 

Just semantics, if you define "stability management" as reducing squat, roll and dive, then yes PASM qualifies. I would imagine PASM is synergistic with PSM by making the laters' yaw control task easier.

btw since you have defined PASM as stability management, does this mean Porsche is off the hook with the 997 GT3 since it only has PASM and not PSM?

OT, but this article on the new Ferrari 599 :

http://www.edmunds.com/insideline/do...ticleId=114909

comments on Ferraris' stability control:

"The second blemish, and we blush to even call it that, is that the "RACE" mode on the manettino summons too much nannying, or control over the car through stability control and traction control. We had expected the F1-Trac and RACE-spec stability to be far more lenient than it was. Instead of coming on like a dimmer switch making minute adjustments/corrections, both the traction and stability controls behaved more like an on/off light switch. Sure, the RACE mode allows some oversteer out of a corner and even recognizes corrective countersteering input, but the safety systems intervene just at the point where a skilled driver could manage to pilot the car even quicker and more adeptly. Once we had moved the selector to CST (control of stability and traction) off, the car came to life as if it just had its lungs filled with oxygen. "Ah-ha!" I exclaimed to myself on the last lap of the day. The car was alive and managing to do exactly as I conducted it to do, and with confidence and authority"

 

also fwiw a review of the 997 GT3:

http://www.autoweek.com/apps/pbcs.dl...3&Profile=1041


"After about 10 or so escorted laps we were allowed a ride with Walter Röhrl, former World Rally champ and for the last several years Porsche’s racing-hero-in-residence. Röhrl didn’t have to drive around any stinking slalom cones. Röhrl just flew.

Yes, we thought, we can do this. Then Röhrl switched off the traction control (there is no stability control) and we thought, no, we probably can’t do this, at least not this well. Or could we? The GT3 makes you feel like you can do anything you want."

 

Any way you want to describe it, PASM is a stability management system. It operates differently from PSM but both are designed to become active when the sensors detect trouble.

PASM is a safety system. It is time for some of you to get your head out of the sand. Yawn.

 

Never argue with idiots - first they drag you down to their level, then they beat you with experience.

 

Colm I have tried to be civil and yet you continue to personally attack me. If you disagree with me fine. There is no reason to make it personal. It does nothing more than to lower the level of discourse on this board.

 

Excuse me I must apologize, I thought it was harmless banter, and all in good fun!