Slow Car Fast

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Re: Slow Car Fast

Postby mrondeau on Mon Apr 02, 2018 5:44 pm

Gary Burch wrote:
GT3 wrote:
And I just corrected my typo, so I guess that set him off... IDK anymore with Mark, maybe I somehow rub him the wrong way, but considering I have barely talked to him since he is not very approachable not sure why.


you need to buy him a drink first



:lol: :beerchug:
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Re: Slow Car Fast

Postby gulf911 on Mon Apr 16, 2018 6:06 pm

ttweed wrote:
GT3 wrote: Here is the million dollar question though... What is the argument when a GT car driver without the years of track experience goes faster than another GT car driver that has many years experience in those older less forgiving cars?

Honestly, the first thing I wonder about in comparing any times between cars on any track is "What tires were they on, and how many heat cycles on them?" Were you on Hoosiers? Was Dan A. on Sport Cup 2s? RE-71Rs?

TT


Sorry , was away for a while and saw the continuing saga... lol

I was on Re-71's Tom. Cup2's are just as fast but maybe not as consistent. I was down over 100hp and tire width ( I run 245/265) at SOW and it was very noticeable on the straights...  :bowdown:
I was happy being that close to an RS , but I do have a lot more experience which helps. I was actually trying to get to 1:21.75 which was what Randy pobst did in a stock gt4... :surr:

RS on SOW IMHO would be 1:19 or less I would think.
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Re: Slow Car Fast

Postby ttweed on Tue Apr 17, 2018 5:49 am

gulf911 wrote:... ( I run 245/265) ...

Are you really running a 265 in the rear, Dan, or is that a typo? I thought the GT4 ran 295s in the back stock.
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Re: Slow Car Fast

Postby gulf911 on Thu Apr 19, 2018 4:04 pm

Sorry Tom, that was a typo , 245 front 285 rear on 19's. Smaller rear to help with push thats typical in front.
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Re: Slow Car Fast

Postby Gary Burch on Thu May 24, 2018 7:35 am

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Re: Slow Car Fast

Postby Jad on Mon May 28, 2018 8:23 am

Interesting article from history. The paragraph that explains my issue with the current systems is this:

"At this point in my career, PSM is an asset
to my racing. It has allowed me to more confidently explore the limits of
traction on the first few laps at a new track, particularly in scarier
corners, e.g., Turn 8 at Willow Springs. I was very happy to have it at
Phoenix International Raceway, a track with concrete barriers everywhere.
When PSM activates you can feel it, much like you can feel ABS. It will
show you where you are losing traction while keeping you on the track if
the loss was unintentional. When it engages, it may slow you down where
you might not want it to later, i.e., where you really do want more
oversteer, but on those first few practice laps, who cares? You can
actually throttle steer the car quite well with PSM on as long as you are
smooth, the yaw is not excessive, and the corner is fast enough to allow
smooth inputs. This in itself is a good training tool. So PSM is good for
practice,"

The new systems are no longer good learning tools. They intervene all the time with no warning or feedback to the driver, so it is virtually impossible to learn because mistakes are never made. Almost anything the driver does is quickly corrected by the car and the driver blindly moves on thinking they did everything right as the results were very good.

I am not saying the new cars are not amazing, or the aides are not wizardry, just that you can't teach or learn with a newer computer controlled car because any input within reason is turned into a proper input by the computer without meaningful feedback or penalty. Much like a PDK transmission, it may be better in every measurable way than a manual transmission, but even though the paddles are 'like' a manual, driving a PDK does not teach you to drive a manual or understand the art of shifting a manual transmission.
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Re: Slow Car Fast

Postby Dan Chambers on Tue May 29, 2018 8:18 am

Jad wrote:The new systems are no longer good learning tools. They intervene all the time with no warning or feedback to the driver, so it is virtually impossible to learn because mistakes are never made. Almost anything the driver does is quickly corrected by the car and the driver blindly moves on thinking they did everything right as the results were very good.

I am not saying the new cars are not amazing, or the aides are not wizardry, just that you can't teach or learn with a newer computer controlled car because any input within reason is turned into a proper input by the computer without meaningful feedback or penalty. Much like a PDK transmission, it may be better in every measurable way than a manual transmission, but even though the paddles are 'like' a manual, driving a PDK does not teach you to drive a manual or understand the art of shifting a manual transmission.


Ah ... the thread that just... won't....die!!

+1 for what Jad states.

Further more, I have come across an interesting observation pertaining to the late-model P-cars with the advanced PSM/PASM feature, and brake pad wear.

It appears that a good portion of the stability control feature relies on the rear brakes keeping the car going in the desired line based on steering input, yaw, wheel rotation speeds related to each other, throttle input, etc. One of the computer's responses is to apply braking to the rear wheels ... independently of the use of the brake pedal ... and individually from rear wheel to rear wheel ... to help steer the car in the desired direction. This application of brakes to the rear wheels for stability purposes can occur at over 60-times a second. Yes; 60 times a second! AND, the braking pressure is calibrated to be "unnoticeable" to the driver. These algorythms were written in to the stability control system to make the driving of the car in a spirited fashion seem easy and smooth. So, when a driver says something like "No, I don't actuate PSM/PASM. I never feel it." My reply is "That's right... and you never will. That's how it was intended and designed."

How do I know that drivers in cars with advanced PSM/PASM are consistantly over-driving their cars? Because their rear brake pads are wearing as fast, or faster, than their front brake pads. In cars without PSM/PASM the front brake pads wear faster than the rear pads by a factor of about 1.5 to 1. Because 60% or more of the braking force is distributed to the front of the car in non-PSM/PASM cars, the brake-pad wear is consistant with the braking force delivered to the braking system. With newer cars equipped with stability control, the people who consistantly over-drive have different brake-pad wear. I've seen it severeal times when tech'ing cars for AX/TT Track events. Yep. Imperical data. I've also seen cars with PSM/PASM where the brake-pad wear is consistant with older cars (minus the PSM/PASM). With some drivers, the front pads are wearing slightly faster than the rear pads even though they have PSM/PASM. These drivers are more experienced, top finishers in their class, and learned in vehicles that had no electronic aids from the 1970's, 1980's, and early 1990's.

I'll leave it up to the reader to make their own assumptions about who is trained better, what vehicle is better suited for learning, who is the "better driver", etc. What I can tell you, as a Tech Inspector, and a driver... and a seasoned Instructor... is that I have my own opinion and a pretty good idea about who is driving at the limit thanks to advanced vehicle design, and who is driving at the limit based on better driving skills. The cars don't hide your secrets. :shock: :oops: Any Tech will tell you that.

Stay cool this summer. 8)
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Re: Slow Car Fast

Postby Gary Burch on Tue May 29, 2018 9:28 am

after re-thinking this,
not sure any of this really matters
nannies are put on a car to make it safer, more predictable, and faster
i have done the same thing, 205/50 71r instead of 165/70 dunlops, can't tell you how many times this has saved me and i didn't even know it, adjustable sway bars, dials in a little more control, lsd=traction control, shocks, torsion bars,etc...
they all make it safer, more predictable, and faster, just not computer controlled.
if you learn to drive in a car with nannies, that is your platform, your base.
they, the nannies, are not going to stop you from over cooking a corner, taking the wrong line, hitting a slalom cone, or putting a wheel off. they will make it a little less unpleasant, but it is still a mistake.
you still have to drive the line, hit the apexes and stay focused, and that comes down to driving.

so if you drive with nannies does it make you less of a driver?
that's what all this is about
it's the old, "i had to walk 12 miles to school, and there were no roads" spiel
the bottom line to being a good driver is the time you turn.
doing a 1:09 on a tough technical ax course is pretty good in anybody's book
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Re: Slow Car Fast

Postby jbrennen on Tue May 29, 2018 10:25 am

Dan Chambers wrote:How do I know that drivers in cars with advanced PSM/PASM are consistantly over-driving their cars? Because their rear brake pads are wearing as fast, or faster, than their front brake pads. In cars without PSM/PASM the front brake pads wear faster than the rear pads by a factor of about 1.5 to 1. Because 60% or more of the braking force is distributed to the front of the car in non-PSM/PASM cars, the brake-pad wear is consistant with the braking force delivered to the braking system. With newer cars equipped with stability control, the people who consistantly over-drive have different brake-pad wear. I've seen it severeal times when tech'ing cars for AX/TT Track events. Yep. Imperical data. I've also seen cars with PSM/PASM where the brake-pad wear is consistant with older cars (minus the PSM/PASM). With some drivers, the front pads are wearing slightly faster than the rear pads even though they have PSM/PASM. These drivers are more experienced, top finishers in their class, and learned in vehicles that had no electronic aids from the 1970's, 1980's, and early 1990's.


I was about to vehemently disagree with this... My rear pads seem to last forever, and I very often run with PSM on. Then I saw the last sentence. :burnout:

(My first autocross championship in 2004 was in a 400 horsepower car with no traction control or stability management...)
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Re: Slow Car Fast

Postby ttweed on Tue May 29, 2018 3:28 pm

OK, Jad and Dan, I understand the sentiment that you guys are trying to express--that learning (and teaching someone) to drive one of the newer Porsches at the limit is problematic, due to the advanced PSM systems with which they are equipped. I agree with that idea, and think that anyone trying to learn basic car control skills should start in a vehicle without them, or lacking that opportunity, should begin their training in a controlled environment with PSM turned off. There is nothing quite like losing control of a car to induce the proper perspective on performance driving risks, and the necessity of developing the correct reactions to prevent such occurrences.

That said, I think you are both mistakenly perpetuating some myths and misinformation about the design and actions of the PSM systems that are not helpful in understanding the nature of the problem, or in developing solutions to the difficulties they present in driver training. The actual situation is quite complex, due to the differences in PSM operation in differing driving modes as well as in differing models of Porsches. Without a complete understanding of these complexities, progress will not be made in overcoming these difficulties. My comments are interspersed in your discussion below.

Jad wrote:The new systems are no longer good learning tools.

Agreed. When active, they mask mistakes in a way that minimize consequences. This is a good thing in terms of preventing damage to the vehicle or injury to the occupants, but is a bad thing in terms of informing the driver of the error they made, thus preventing development of proper inputs and actions in a given situation. I understand your dilemma as instructors in attempting to explain a mistake to a student whose car corrected it instantly. They don't believe you because there was no serious consequence. That is a problem.

They intervene all the time with no warning or feedback to the driver.

This is not true. Every intervention by PSM is signaled to the driver by the PSM warning light on the dash, if the system is functioning. This is explicitly stated in the technical documentation, and Porsche would be negligent to not inform the driver, as PSM intervention is a warning that the driver's actions are not appropriate in the current driving conditions and should be altered. They state in several sections of the driver's manual that "Your Porsche sports car features a complex integrated system made up of all control systems acting in power transmission and in the chassis...Despite the advantages of transmission and chassis control systems, it is still the driver's responsibility to adapt his driving style and maneuvers in line with road and weather conditions, as well as the traffic situation. The increased safety that is provided should not induce you to take greater risks with your safety. The limits set by the physics of driving cannot be overcome. These systems cannot reduce the risk of accidents due to inappropriate speed. Adapt your driving style, maneuvers and speed to the road and weather conditions, as well as the traffic situation."
and
"In spite of the advantages of PSM, it is still the driver's responsibility to adapt his driving style and maneuvers in line with road and weather conditions, as well as the traffic situation. The increased safety that is provided should not induce you to take greater risks with your safety. The limits set by the physics of driving cannot be overcome, even with PSM. Risk of accidents due to inappropriate speed cannot be reduced by PSM." If Porsche made the operation of these systems "invisible" to the driver, they would incur considerable liability, and they know this. They absolutely want the driver to know when it is happening.

Unfortunately, in a performance driving situation, a dash light flashing on may not be noticed by either the driver or the instructor, due to attention being focused on the track. I happen to think that there should be a distinctive audible "chime" (or maybe a "buzzer") associated with any PSM intervention as a more effective warning, but that is another subject, one I have actually communicated to Porsche engineers separately. However, there are other effects of PSM intervention that are definitely noticeable, by both driver and instructor, and if we do not become more familiar with them. progress in dealing with this dilemma will be impossible. I have mentioned them before in this thread, but maybe reading them in the actual manual for the 2012-2016 Carrera model would be useful:
http://www.porscheownersmanuals.com/2012-911-carrera-manual/6/161/ABD-automatic-brake-differential
The events below inform the driver of PSM control operations and warn him to adapt his driving style to the road conditions:
– PSM warning light on the instrument panel flashes.
– Hydraulic noises can be heard.
– The vehicle decelerates and steering-wheel forces are altered as PSM controls the brakes.
– Reduced engine power.
– The brake pedal pulsates and its position is changed during braking.


All the various Porsche electronic control systems are networked with the aim of combining the best possible driving performance with maximum safety. Many of the "performance" systems truly are "invisible," like PASM, PDCC, PADM, and rear-wheel steering, etc., but the safety portions of PSM to ensure vehicle stability in extreme situations are very much apparent, especially in "Sport" driving mode when pushed to the limits of stability. Without being aware of them, and having enough seat time in such cars to detect their effects, both students and instructors will be at a loss to deal with the issues raised here.

Dan Chambers wrote:It appears that a good portion of the stability control feature relies on the rear brakes keeping the car going in the desired line based on steering input, yaw, wheel rotation speeds related to each other, throttle input, etc. One of the computer's responses is to apply braking to the rear wheels ... independently of the use of the brake pedal ... and individually from rear wheel to rear wheel ... to help steer the car in the desired direction. This application of brakes to the rear wheels for stability purposes can occur at over 60-times a second. Yes; 60 times a second! AND, the braking pressure is calibrated to be "unnoticeable" to the driver.

These algorythms were written in to the stability control system to make the driving of the car in a spirited fashion seem easy and smooth. So, when a driver says something like "No, I don't actuate PSM/PASM. I never feel it." My reply is "That's right... and you never will. That's how it was intended and designed."

How do I know that drivers in cars with advanced PSM/PASM are consistantly over-driving their cars? Because their rear brake pads are wearing as fast, or faster, than their front brake pads. In cars without PSM/PASM the front brake pads wear faster than the rear pads by a factor of about 1.5 to 1. Because 60% or more of the braking force is distributed to the front of the car in non-PSM/PASM cars, the brake-pad wear is consistant with the braking force delivered to the braking system. With newer cars equipped with stability control, the people who consistantly over-drive have different brake-pad wear.

This is incorrect for a couple of reasons, Dan. First of all, there are two different systems involved in this situation which you are conflating, PTV (Porsche Torque Vectoring) and ABD (Automatic Brake Differential). PASM (Porsche Active Suspension Management) is not involved with PSM or brake activation at all, it is simply an active electronic adjustment of the dampening characteristics of the shock absorbers, so why you mention PASM at all in this context is a mystery to me. All new Porsches are delivered with PSM (calibrated in different ways in different models) but only a portion of them are even optioned with PASM, so stating "PSM/PASM" makes no sense to me.

It is true that PTV uses the rear brakes alone, in conjunction with the rear differential lock, to distribute a greater amount of drive force to the outside rear wheel in a turn, which has more traction from being loaded, and prevents wheelspin on the inside wheel, which is unweighted. This also imparts a greater axial force on turn-in, making it feel more crisp and "sporty." However, this is a gentle application of the brakes, which can indeed be "invisible" to the driver, and happens even without "overdriving" the car. It engages as a performance enhancement even in moderately "spirited" cornering, when vehicle instability is not yet an issue. It is not a component of PSM at all (although PTV Plus, which is only available on PDK cars, can work in conjunction with PSM in a minor way on road surfaces with varying grip as well as in the wet and snow, due to its fully variable torque distribution).

ABD, on the other hand, is the "stability management" portion of the electronic braking system, and it intervenes for safety, not performance, in hard cornering situations (although it does have some minor performance application along with ASR in controlling wheel spin when accelerating in a straight line as well). When it intervenes, it is an abrupt and strong influence on the car's motion, and definitely noticeable, always slowing the car considerably and making weird hydraulic noises. It operates on all four wheels independently, not just the rears. If you suffer extreme understeer in a turn, the rear wheel on the inside of the bend is braked as necessary to bring the car onto the desired arc. If you suffer extreme oversteer, the front wheel on the outside of the bend is braked. It is conceivable that someone who constantly tries to kick out the rear to rotate the car and corners in an oversteering slide all the time (without ever entering corners too hot and suffering understeer) could actually wear the front brakes faster than the rears due to ABD intervention. I tend to believe that the reports of accelerated brake wear in the rear are coming from people driving cars hard that have no limited slip differentials at all, and ABD is kept really busy limiting wheel spin in the rear. This is especially true of many of the newer mid-engine cars that are often not even optioned with PTV or any LSD and don't have the rear weight distribution of the 911. After working tech inspection for almost 20 years now, I certainly wouldn't assume that differential F/R brake wear is necessarily a sure sign of someone overdriving the car. It can easily be that someone has replaced the front pads without doing the rears, since the fronts wear so much faster. Unless the owner verified that pads have never been changed, or all 4 wheels were done at the same time, I'm not sure you could make an automatic assumption that PSM caused the differential wear.

Finally, the differences between PSM in different modes and models must be understood for effective instruction to take place. In the lower tier models, activating Sport or Sport Plus mode widens the allowable range of deviation. This is what the manual says: "PSM interventions occur later than in Normal mode. The vehicle can be maneuvered with greater agility at its performance limits, without having to dispense with the assistance of PSM in emergency situations. This helps to achieve optimal lap times, particularly on race circuits and on a dry road surface." (This is a tacit admission by the folks who make these cars that PSM does not help you go faster than a good driver could with it off, but while it may slow you down, at least you won't crash before you can make it around the track!) After you turn PSM off, when you then apply brakes in the ABS control range, the vehicle is stabilized even when PSM is switched off. One-sided spinning of the wheels is prevented, even with PSM switched off. The vehicle retains its enhanced braking readiness through prefilling of the brake system even when PSM is switched off. Wheel-specific brake interventions and the anti-slip control system (ASR) are also switched off. The automatic brake differential (ABD) remains on. By contrast, in the GT models, there is no Sport or Sport Plus mode. PSM is permanently calibrated in a sportier manner, allowing more latitude than even Sport Plus in the other cars. PSM can be switched off in 2 stages:
– Stage 1 ESC OFF:
Switches off Electronic Stability Control (ESC).
– Stage 2 ESC+TC OFF:
Also switches off Traction Control (TC).
There is no stabilizing brake control in either of the switch-off stages (even when the brakes are used in the ABS range). Note that Traction Control cannot be disabled without first turning off Stability Control.

I hope this information better informs our discussions of these issues.
(BTW, after 3 years of AX events, my GT3 brake pads are showing no abnormal wear differential, they are at about 70% F and 85% R)
TT
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Re: Slow Car Fast

Postby Jad on Tue May 29, 2018 7:03 pm

Tom, I pretty much agree 100% with what you said. My problem is the 90% of the new Porsche drivers do not even begin to understand what you just said. Therein is the issue. They don't want to risk their cars by learning without the systems off, and I don't blame them. I always leave the systems on when I drive a students car. We have had, lets just say 10+ years of doing this :roll: , but the speed things happen in a modern car are crazy even after many years of experience and working up to it.

This thread is mostly pointless now, as anyone still reading is not the issue. We shall see what the future brings to high performance driving.
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Re: Slow Car Fast

Postby Old Guy on Tue May 29, 2018 11:27 pm

My brain is burning. Too much information. That said: helpful. I will read it all again with my 911 owner's manual in hand. I spent Sunday the 27th at Fontana with our '05 Comp Pkg BMW M3; 5 sessions, 140+ track miles; 5 sessions. Almost everyone passed me at least once; did not have an Instructor and for sure messed up a few of the turns. In my defense, I just couldn't bring myself to top 125 mph on the main straight or +/- 110 through the banked turn. My garage mates (left side new 911 Turbo, right side new M4 GTI) reported running 145-160 mph...too fast for me. I ran in M mode...pretty helpful for avoiding excessive traction control intervention on the slower corners. But...my lines even I could see were not the best. But my tires look great, so my tire pressure selection and Charlies' corner balancing and alignment adjustments were well done.

But to the point of this thread, end of June I'm doing a Fast Toys Club event at Fontana with our '17 Carrera. The very last thing I want to do is stuff this (not yet paid for) car into the wall. (The 27th we had a Lambo somethingorother in one session that went by me on the banking like I wasn't even there. It was red.) For the Fast Toys Club event I'm sure there will be many "super" cars, leaving me as the cheapo outsider. Nevertheless, my objective is to give it a go and see what our car will do. Also will have an Instructor, as needed/wanted. This thread would seem to opine that the 911 will look after me no matter how stupid I drive. Vamos a ver. My plan is to run in Sport mode to allow rev-matching for our 7 speed manual. Not expecting to use other than 3rd and 4th gears, all things considered.

Will anyone else from our Chapter be at the event on Wednesday the 27th??
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Re: Slow Car Fast

Postby Jad on Wed May 30, 2018 7:33 am

Hi Jim,

Yes the '17 Porsche will completely take care of you with the driving you are describing! Just don't get overconfident in your abilities, and assume the '05 BMW will do nearly as good a job in protecting you at the follow on event. The Porsche is worlds ahead in smoothness and ability in computer aided driving. Sounds like you have the right attitude, versus the Lambo etc going 160 mph. I have no experience as to how well the new computers perform at those speeds, but I am willing to bet a bad enough input will beat the safety net.

Enjoy!
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Re: Slow Car Fast

Postby Dan Chambers on Wed May 30, 2018 10:37 am

Tom: thanks for the clarification of the system(s). I profess to knowing very little about in-depth and intricate understandings of how the electonic assist systems work in the newer cars, such that you do. I only know what I've been told by numerous technicians that work on them (both certified and not-so-certified mechanics). Thus, my references to PSM/PASM were sourced from others.

So... allow me to edit my previous post thusly:

" I have noticed in the last couple of years that vehicles equipped with 'electronic driver aids' appear to have an effect on the way brake pads wear. For vehicles equipped with electronics aids, with drivers who appear to over-drive their cars, the rear brake pads appear to wear as quickly, or even quicker than the front pads. In cars equipped with electronic driver aids, with drivers who do not consistantly over-drive their cars, the brake pad wear patterns appear to emmulate those earlier vehicles not equipped with electronic driver aids. These observations are based on numerous Tech Inspections performed by me at both AX's and TT's on cars equipped with electronic aids and cars without electronic aid equipment. These observations have been repeated numerous times, leading me to belive there may be a pattern developing in the relationship between electronic aided driving, driving styles, and brake wear anomolies."

Hope that helps.

Jad: +1. Time will tell in regard to the new Electronically Assisted Performance Driving paradigm.
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Re: Slow Car Fast

Postby ttweed on Wed May 30, 2018 3:37 pm

Dan Chambers wrote:Jad: +1. Time will tell in regard to the new Electronically Assisted Performance Driving paradigm.

I am probably not the guy to comment on the issue of instructing in the newer cars, since I haven't been doing the big track events for over 4 years now, and gave up instructing over 3 years ago. Even when I was instructing regularly, I was almost always paired with students in older air-cooled cars because that's what I drove. I did have one experience with a student spinning a 997 GT3 despite it having an earlier version of PSM, so I do believe that physics is not just another good idea, it's the law! As Porsche says repeatedly in their driver's manual, despite the sophistication and complexity of the newest PSM systems, they can't save you from everything. Since safety is THE most important priority in our track events, exceeding the secondary goal of having fun by challenging ourselves and our machines, I think we have to welcome the advancements in safety that these systems represent, while recognizing that we shouldn't accept the computerized nannies substituting entirely for driving skills. Taken to the extreme, computers could eventually drive the car completely around the track unassisted, and with enough computer power and sufficient programming, could probably do it faster than us--but where would the fun be in that?

We have always had a qualifying procedure for the performance driving pyramid in the club--from autocross to DE/TT to club racing. Instructors, CDIs, and race stewards are the "gatekeepers" along the way. Students have to prove their ability to drive safely and proficiently at each level before they solo or advance. The only things that are changing lately are the cars are getting faster out of the box, without any modifications, and they are equipped with electronic systems to keep them safer, which masks deficiencies in driver skill and instills unwarranted confidence in students, encouraging them to drive at speeds that exceed their talent. At some point, they may also exceed the ability of the nannies to save them, and then we are back to the safety issue, at an even higher and more severe level. The challenge, it seems to me, is still the same--how do we mitigate the safety issues and still have fun?

Putting aside the safety equipment modifications necessary for cars with the tremendous speed potential of the modern, stock Porsches (which is an easily "legislated" issue, using the rule set), we are left with the thorny issue of instructing and approving students to climb the hierarchy of speed when the nannies prevent them from experiencing the consequences of their mistakes. It used to be that spins and off-track excursions naturally revealed inadequacies and instilled the proper level of fear and respect to curb excessive enthusiasm and confidence. Students were forced to analyze their misjudgments and motivated to work on developing the automatic responses to correct the car's attitude before it gets too far out of control. I'm not sure what can replace that other than forceful instruction and more rigorous qualification to advance to the next level.

Personally, I don't think any student who hasn't demonstrated the ability to control their cars at an autox without the PSM safety net, consistently judge corner entry and exit speeds, braking points, correct understeer and oversteer slides instinctively, etc., should advance to the DE/TT level. I don't see any problem with making people learn car control without nanny intervention at the AX level. It wasn't that long ago when everyone did that. The speeds are low and the hard, fixed objects are fairly well removed from the course.

Once they move up to the big track, I would encourage everyone to use electronic aids if they have them. But instructors and students must be aware of the PSM interventions and treat them seriously, as the mistakes they are. I think that all instances of electronic intervention of the "safety" type that correct instability should be treated in the same way as they would have been in the old, analog cars. Every new student in a "nanny" car (and all instructors paired with them) should be familiar with the nature of the car's electronic aids beforehand, and the instructor should brief them before the first session that interventions should be strictly avoided. If PSM is set to Sport (or Sport+) mode, there should be plenty of latitude for them to set a good lap time if driven cleanly. Then, every such instance of intervention must be recognized, pointed out, discussed, and resolved as the mistake it is. If the intervention is minor, of the type that would have just resulted in a lurid slide or off-line event in the past, it should be treated in that way--discussed in a post-session debrief as a mistake that resulted in a slower lap. The emphasis should be that the nanny intervention slows you down, and the smoother lap with no intervention would be faster. If the intervention is serious enough to correct imminent instability, it should be treated in the same way that spins and offs were treated in the past--by pulling off the track, discussing the circumstances to ascertain if the student understands what happened and is capable of preventing it going forward, etc., just like a visit to the black flag marshal. Repeated incidents due to incompetence or disregard of the instructor should be treated with escalating consequences, up to and including sitting out a session or expulsion from the event.

That's my $0.02, and as I said, I have no skin in this game anymore, so it's really up to the instructor corps and the "powers that be."

TT
Tom Tweed -- #908
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