Motor Trend Car of the Year
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Easy to say. But by your own admission, it took getting used to (a different way to handle a car).
I've read many, many, many times - where people say,"I've driven 'x' number laps around 'y' track in previous 911's, and 'z' car sucks." - after about 3 laps.
I completely agree that new technology isn't designed to be crap, and most likely improves performance/experience, etc..., doesn't mean it gets a fair chance during it's debut.
So how do you 'try' it before buying? Last I heard, dealers don't exactly give 2 month test-drives, with a couple weekends at an HPDE.
(There is the Porsche driving event, though)
I've read many, many, many times - where people say,"I've driven 'x' number laps around 'y' track in previous 911's, and 'z' car sucks." - after about 3 laps.
I completely agree that new technology isn't designed to be crap, and most likely improves performance/experience, etc..., doesn't mean it gets a fair chance during it's debut.
So how do you 'try' it before buying? Last I heard, dealers don't exactly give 2 month test-drives, with a couple weekends at an HPDE.
(There is the Porsche driving event, though)
Sure, dealers don't give 2 months long test drives but they do or should provide you with enough short drives to help you decide what is right for you. My dealer did not have a pdcc car available for test driving but their tech was happy to spend a lot of time with me to help me be better informed.
I think the questions is about PDDC. In my opinion it would make the handling a little artificial. I am surprised that it increases understeer. I personally did not order PDDC on my CS. I think I saw a video from motorTrend comparing the non-PDDC CS with a PDDC and the like the non-PDDC better....
As I mentioned, i feel reviewers are sticking a label of understeer to their experience...what they are experiencing is something new and not classic understeer. I don't think pdcc increases understeer. It does make you drive the car differently and once confidence is gained, more aggressively when the situation presents itself... like on uneven fast twisties etc.... Or the track.
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... I have tracked a 997S and a 991S. The 991S is more fun, and it does not understeer. Not at all the way I drive it, but we do have to allow for Porsche's use of 'straddle' in their designs to accommodate expert drivers without killing casual owners. (A sound goal I suppose.) I would say that driven ... casually... a 991S still would have less than twenty percent of the understeer found in the 997S....
And when I did something really bad, like lifting at corners, I can get the rear to slide (not in a good way). It is still a 911, but the best one yet. It gives me a lot of confidence on the track, yet still a superb daily driver. I have no regrets.
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So they put in all this extra stuff to make it handle as good as the lower model. Awesome.
Imagine if all of that engineering went into the Cayman - how good would it be?
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Well, Cayman is mid-engine and has inherited balance advantage in handling. However, I did say the 991 still retains the rear-engined advantage on track out - you can accelerate earlier after turn in, much earlier than the other platforms, and this advantage alone is hugely addictive and fun. I never fully understood the addictive nature of 911 until I drove on the track.
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I'm a little hesitant to comment about base model Carreras, with which I've had limited experience, and I'll definitely stay out of the Tesla debate. A smart engineer doesn't 'do' politics. But as for the S models of Carrera, I can contribute to that discussion at least. I have tracked a 997S and a 991S. The 991S is more fun, and it does not understeer. Not at all the way I drive it, but we do have to allow for Porsche's use of 'straddle' in their designs to accommodate expert drivers without killing casual owners. (A sound goal I suppose.) I would say that driven ... casually... a 991S still would have less than twenty percent of the understeer found in the 997S.
Now about that understeer even under "mild lift-throttle conditions". I didn't want PDCC on my car and ordered it with only the usual performance options, but it sounds like they are trying to balance the car on throttle and not succeeding as easily as is usual. I haven't time to read the article, but I can guess what is happening in those conditions. Porsche has been concerned since about 1975 with what came to be called the Ferraria effect. (Not related to Enzo Ferrari so far as I know. Probably some dynamicist.) It's well known to racing drivers and most expert road drivers. At high lateral loads, thrust from the rear wheels is required to counter the drag, and our cars are set up for that. That thrust keeps the car balanced. We use throttle variations instead of steering wheel movement on a sustained corner. But dropping the thrust completely causes a significant weight transfer forward. Absent suspension settings that compensate by adapting the contact patch, the result is lower clamping pressure in the rear and increased in the front. If the weight transfer is accompanied by body pitch, the suspension may create undesirable changes in the rear contact patch. (Consider 'jacking' in the swing axle cars.) That exacerbates the situation rapidly.
That phenomenon is what causes mid-seventies 991 S models to need expert attention near the limit. Back out of a corner and you're facing backward literally. Curing that tendency has been the subject of complex suspension analyses and a few witch doctor treatments (like the weighted front bumpers). I surmise that the PDCC actions that balance the car also dampen even the desirable early Ferraria effects that let us throttle steer in corners. What we do normally probably is changing the slip angles at the rear enough to justify the term 'oversteer' being applied, so getting rid of that probably would feel like understeer even if technically it was only neutral behavior achieved by computer control. I'd have to drive an example to say anything without the "maybes" and "might be"s sprinkled through the sentence.
My 991S does not exhibit extreme Ferraria. I doubt any unmodified Porsche of the last ten years would do that. It does handle like a race car in terms of balancing on the throttle and changing direction nimbly. It has PASM responses similar to the full-time PDCC actions that will kick in if PSM is activated. They are intended to keep an essentially neutral car from inducing a Ferrarria spin. Since I've never seen PSM activate on one of my own laps, I consider that 'straddle' feature a decent trade-off for the agile handling the 991S has the rest of the time. I'm sure people who do startle PSM into action are happy for the help preventing a snap spin.
The PDCC sounds like an overcompensation at worst, and most likely a change in driving feel rather than true understeer like we tolerate in our 997 models all the time. It makes me wonder how 'significant' this understeer was and whether their drivers made such abrupt control movements that PSM did indeed kick in to save their butts. But that's probably unfair. A change in feel is more likely, and I have to say its a change I didn't want. That's why I don't have PDCC.
Since it is an option, not a feature, on either new Carrera, it is properly a criticism of the PDCC feature, not either type of Carrera.
Bottom line: Don't order PDCC if you're concerned about handling feel, but we've known that since the early reviews. Do order it if you want the fastest times on high speed tracks. The loss of feel is balanced by increased grip at the limits.
Gary, old enough to prefer fun to lap times
Now about that understeer even under "mild lift-throttle conditions". I didn't want PDCC on my car and ordered it with only the usual performance options, but it sounds like they are trying to balance the car on throttle and not succeeding as easily as is usual. I haven't time to read the article, but I can guess what is happening in those conditions. Porsche has been concerned since about 1975 with what came to be called the Ferraria effect. (Not related to Enzo Ferrari so far as I know. Probably some dynamicist.) It's well known to racing drivers and most expert road drivers. At high lateral loads, thrust from the rear wheels is required to counter the drag, and our cars are set up for that. That thrust keeps the car balanced. We use throttle variations instead of steering wheel movement on a sustained corner. But dropping the thrust completely causes a significant weight transfer forward. Absent suspension settings that compensate by adapting the contact patch, the result is lower clamping pressure in the rear and increased in the front. If the weight transfer is accompanied by body pitch, the suspension may create undesirable changes in the rear contact patch. (Consider 'jacking' in the swing axle cars.) That exacerbates the situation rapidly.
That phenomenon is what causes mid-seventies 991 S models to need expert attention near the limit. Back out of a corner and you're facing backward literally. Curing that tendency has been the subject of complex suspension analyses and a few witch doctor treatments (like the weighted front bumpers). I surmise that the PDCC actions that balance the car also dampen even the desirable early Ferraria effects that let us throttle steer in corners. What we do normally probably is changing the slip angles at the rear enough to justify the term 'oversteer' being applied, so getting rid of that probably would feel like understeer even if technically it was only neutral behavior achieved by computer control. I'd have to drive an example to say anything without the "maybes" and "might be"s sprinkled through the sentence.
My 991S does not exhibit extreme Ferraria. I doubt any unmodified Porsche of the last ten years would do that. It does handle like a race car in terms of balancing on the throttle and changing direction nimbly. It has PASM responses similar to the full-time PDCC actions that will kick in if PSM is activated. They are intended to keep an essentially neutral car from inducing a Ferrarria spin. Since I've never seen PSM activate on one of my own laps, I consider that 'straddle' feature a decent trade-off for the agile handling the 991S has the rest of the time. I'm sure people who do startle PSM into action are happy for the help preventing a snap spin.
The PDCC sounds like an overcompensation at worst, and most likely a change in driving feel rather than true understeer like we tolerate in our 997 models all the time. It makes me wonder how 'significant' this understeer was and whether their drivers made such abrupt control movements that PSM did indeed kick in to save their butts. But that's probably unfair. A change in feel is more likely, and I have to say its a change I didn't want. That's why I don't have PDCC.
Since it is an option, not a feature, on either new Carrera, it is properly a criticism of the PDCC feature, not either type of Carrera.
Bottom line: Don't order PDCC if you're concerned about handling feel, but we've known that since the early reviews. Do order it if you want the fastest times on high speed tracks. The loss of feel is balanced by increased grip at the limits.
Gary, old enough to prefer fun to lap times
Nice write-up Gary!!! I think I understand all your logic except you didn't quote any lap times quicker with PDCC than without it in the last paragraph (and the figure 8's were slower). Did I miss that?
ChuckJ
PS I'm sure you meant 911 in paragraph 3 rather than 991, correct?
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What I find entertaining is how difficult it is to grasp engineering design goals, not to mention marketing targets. Even people who ought to know the industry say stupid things like "Oh, yeah. They hold down the power on the Boxster so it won't out-do a Carrera Cabriolet." If they want a convertible with the power of a Cabriolet, all they have to do is turn around. It's parked in the next slot at any dealer. That's what results from a balanced engineering effort to give one car the traits of another. You get a different car and darned if you won't find that different car being marketed under another name.
What they want of course is a Boxster price with a Cab's engineering and performance. Or in this case, a Cayman price for the Carrera.
We'll work on that.
Gary
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simsgw:
Nice write-up Gary!!! I think I understand all your logic except you didn't quote any lap times quicker with PDCC than without it in the last paragraph (and the figure 8's were slower). Did I miss that?
ChuckJ
PS I'm sure you meant 911 in paragraph 3 rather than 991, correct?
Nice write-up Gary!!! I think I understand all your logic except you didn't quote any lap times quicker with PDCC than without it in the last paragraph (and the figure 8's were slower). Did I miss that?
ChuckJ
PS I'm sure you meant 911 in paragraph 3 rather than 991, correct?
But I do keep a Google watch on "Nurburgring lap times" out of curiosity. I remember seeing faster times from PDCC-equipped cars than the same car without. I don't think I've ever driven a figure eight in my life. The races I saw that way scarred me in my childhood I'm sure. I can't bring myself to care how fast any particular car went in that format since I disagree with anyone who considers it representative of a real world lap time, let alone performance over public roads.
Gary
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Yes, I did. To answer the last question first. I'll go fix that in a moment. I didn't quote the lap times for an excellent technical reason. I'm lazy.
But I do keep a Google watch on "Nurburgring lap times" out of curiosity. I remember seeing faster times from PDCC-equipped cars than the same car without. I don't think I've ever driven a figure eight in my life. The races I saw that way scarred me in my childhood I'm sure. I can't bring myself to care how fast any particular car went in that format since I disagree with anyone who considers it representative of a real world lap time, let alone performance over public roads.
Gary
But I do keep a Google watch on "Nurburgring lap times" out of curiosity. I remember seeing faster times from PDCC-equipped cars than the same car without. I don't think I've ever driven a figure eight in my life. The races I saw that way scarred me in my childhood I'm sure. I can't bring myself to care how fast any particular car went in that format since I disagree with anyone who considers it representative of a real world lap time, let alone performance over public roads.
Gary
Wonder if the 918 has PDCC as I think it has a great lap time and 4wd. Do you know?
ChuckJ
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Gary
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