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Old 12-01-2013, 10:27 PM
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Default Re: Our Lives With Technology - Part II

View presented here are my personal views and are not representative of views of PCA, Porsche or any other entity/person.


The new models from Porsche, including the 981 and 991 series, have increased electronics. Electric steering systems (no more boiling hydraulic fluid at the track), better EBD (totally independent four-wheel braking depending on sensors’ input), improved PASM, improved dynamic engine mounts (DEM), torque vectoring (PTV), automatic aero dynamics, PDK+, and of course, four-wheel steering (4WS) just to list few. The manual-transmission 991 Carrera S with Sport Chrono + even has heel-and-toe automatically all day long preserving the transmission and synchros.

PTV is particularly interesting to me; listening to some drivers who rave about this system, it is a wonder, how in the world we have driven without it all these decades? You turn into a corner and if the G sensors record certain levels, along with a slip angle threshold, a not-so-appropriate steering angle and inappropriate throttle or brake pedal pressures, the computer very cleverly computes that you need some assistance in turning the car gracefully in the direction that is intended. This is a very clever evolution of the EBD; PTV combines the EBD’s ability to individually modulate brake pressure at each of the wheels independently with a lightly tuned and infinitely adjustable electronic rear differential. The result is driving ability that most mortals don’t have using only hands and feet. Of course we pay more for the privilege of having such technology in our latest models that make us look as amazing drivers in the name of increased safety. Add to all this the 4WS system that dynamically modifies the toe angle at the rear of the car, and PDK+ that makes sure you are in the right gear at all times without moving a single finger, we all become unbeatable. Who wouldn’t want this? Track records will be broken, no doubt.
Mercedes now has even more technology in its latest models that I thought it was never possible. I won’t go into the details, but suffice it to say that the car even monitors your eye pupils to determine if you need a break from driving, has infrared cameras for better visibility, a system that maximizes brake pressure depending on conditions and front distance sensors detecting objects, on and on. For a luxury oriented Mercedes it is normal I think, but I would not want to take an S class Merc to the track.

It was just handful of years ago nearly all of us criticized the Nissan GTR R35 for being too easy to drive with its automatic dual-clutch transmission, multi-level stability, suspension and differential controls, and of course its clever 4WD system biased towards rear-drive. Can we argue that today 991 or 981 provide a more authentic driving experiences than a GTR?

One significant safety issue is emerging across multiple brands. For several years now many drivers of sports cars from Porsche (987/981/997/991), Ford (Boss 302), Nissan (350Z/370Z), Subaru (BRZ), Toyota (FRS, Corolla), Lotus (Elise), etc. have been reporting this scary phenomenon referred to as “ice pedal” or “ice mode.” This is the situation when approaching a corner at high speed and driver hits the brake pedal and pedal feels as a brick and bake pressure is reduced significantly or is not available at all. Across the message forums of all the cars I listed above have experienced this dangerous situation. Not every driver experiences it, I certainly haven’t in my 997, but there are enough drivers experiencing the sensation that it has become a real discussion topic. The number of variables involved in the situation is significant that I have not been able to determine much of a common denominator between them. The cars have different ECU manufacturers and codes, each model has different brake systems from master cylinders to calipers; some situations involve left-foot braking, some trail braking, and some straight-line braking. Some drivers claim pumping the brake pedal restores braking forces and pedal feel, others report no real effects. Some drivers and technicians relate the issue to calipers flexing and/or to bumpy surfaces creating knock-back in calipers, but others claim the situation can be reproduced in their cars under any circumstances, some cannot even quite positively describe the circumstances the issue occurs. The configuration of the cars that experience ice pedal range from having modified suspensions, race or street tires, smaller or bigger tire diameters from original and of course different braking techniques.

From what I can determine by just reading the experiences, which is not scientific or technical in any way, the only common elements at ABS with EBD function, and automatic emergency braking and/or cars that don’t allow brake and throttle overlap to avoid “unintended acceleration” problem that Audi and Toyota has suffered in the past. It appears to me that when the ECU records a combination of readings from the sensors it tries to intervene in a way to stabilize the car for better control. I am of course completely speculating as I have no clue how these systems are engineered; however, it is probably not a coincidence that the racing version of the ECUs do not exhibit these issues as they lack all those systems, maybe save for ABS. Reality is I don’t think most of us fully understand the problem and cannot even determine if it is an issue that drivers can overcome with a different driving style, or it is a mechanical and/or electronic issue that is outside of the drivers’ control. However, I personally think, this is a relatively new issue we have been seeing since 2005-2006 at which time majority of the electronics that were embedded into the safety systems of the vehicles.

Although there is no question that such computational technologies have increased driver safety and vehicle performance, depending on a small group of computer programmers and vehicle dynamics engineers has created unintended consequences over the years as well as removing some of the involvement drivers used to enjoy and we have been gradually losing the authenticity a good sports car extended to us.

Would it be too surprising to you if Porsche announces that the next generation of 911 GT3 will have Porsche Dynamic Countersteering System (PDCS)? I am making this up of course, at least I sincerely hope so. Imagine that the ECU determines that the driver has gone into a corner a little too hot with too much steering angle, PTV is not sufficient to bring the car in line and as a last resort it decides to increase the steering angle in the opposite direction to the intended travel path because the rear slip angle has exceeded tolerances. The ECU dynamically decides and electrically changes the front wheel angle independent of the driver’s steering wheel position to counter balance the oversteer for a perfect drift through the corner. With electric steering that has no mechanical connection to the steering wheel, couple of additional G-sensors front and aft, and one additional hexa-core processor, it can all be done, just supplement with couple of new lines of codes and voila! We won’t even need track instructors any more, just throw the car into a corner PTV, EBD, eDiff and PCDS will sort it out, just hold on to the steering wheel; and what ever you do just “do not turn off ESC off, even professional drivers are faster with it on.”
The E30 and E36 M3, 996 GT2/GT3, the F40 are the bookstores I keep looking to find even if it just to look at the cover, but I hardly ever see them nowadays. I will stick with the 997 GT3 as long as I am be able, I think it is truly the last semi-analog sports car I care to have, certainly the last GT3 with the Mezger engine.

Although my opinion hasn’t changed from what I have stated thus far above, I also acknowledge the difficulties manufacturers have in designing and manufacturing products that continuously excite us, while balancing the need for safety. The power levels of the engines stuffed into the vehicles keep increasing, which generates tremendous excitement. To be able to control such explosive power, literally, manufacturers cannot rely on our confidence that we will be able to control the vehicles under any circumstance. In 2007 Porsche was sued for its alleged involvement in Mr. Ben Keaton’s death while driving a Carrera GT on the racetrack and crashing due to various reasons that occurred at the event and prior. It was alleged that Porsche was negligent by not putting stability control mechanism in the CGT. Eventually all parties settled the issue outside of the courts and I do not know the details beyond that.

With Mr. Paul Walker’s and his friend Mr. Roger Rodas’ passing this weekend due to a horrific crash in a CGT, it served me as a reminder as fun as cars maybe we as drivers take on a significant responsibility driving them on public roads. We all have moments in which we feel invincible and sometimes go beyond what is ethically the right way to drive on such roads. Top that off with a society that we built based on litigation that forces manufacturers to put warnings that say “do not iron cloths while wearing them” we all have to accept that car manufacturers have to put the most safety features in their ultimate performance cars as possible.

As I said, it still does not make me change my mind at this time, I wish we had less electronics to help us drive and more mechanical and aerodynamic aids. As it is evolving however, we also have to evolve the meaning of the terms “involvement” and “authentic.”
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Fatih Selekler
997.2 GT3
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