PASM, PTV, AWD, and PDCC -- Oh My!
#17
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Nice post. You remind me of LJK Setright without the pomposity.
Have you ever driven a Cayenne GTS? I tested the previous gen a couple of years ago and was very impressed. I thought it had better "flow" than the Panamera. Probably due to soft, long travel suspension and well judged damping.
Have you ever driven a Cayenne GTS? I tested the previous gen a couple of years ago and was very impressed. I thought it had better "flow" than the Panamera. Probably due to soft, long travel suspension and well judged damping.
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Great post and a wonderful read, thanks Gary.
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Wow, great post. As I'm currently weighing options, this was extremely helpful. You're a great writer, and obviously an unparalleled lover of fine cars. Great combination! Thanks for the help...
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fantastic post, gary, thank you. it sounds like porsche really got the 4s agility just right in the 991 compared to previous models. i wonder if you think the power assisted steering might also be part of the magical equation with the awd version? also, it would have been interesting to see a c2s with pdcc in the mix, but perhaps that could be part of another chapter!
- My own C2S compares to the C4S nicely in weight. About a twenty pound difference, and that let me assess the difference in vehicle dynamics. To compare the C2S PDCC, I'd have needed to drive two more cars: C2S Coupe back to back with a C2S PDCC Coupe. And honestly, I wasn't up to it. It was a fun weekend, but adding a concours and Zone dinner to those test drives left me pretty exhausted by Sunday night.
- I couldn't find a C2S PDCC coupe. In the L.A. market, you'd think it would be easy, but it was privately explained. No dealer wants a car that sits very long because inventory cost adds up. In a small market, a dealer might have only two new Carreras at any given time, so buyers have less choice and are inclined to accept the options the dealer chose. Anything but a deal-breaker gets shrugged off in a car already as expensive as ours.
But in a market like Los Angeles, we have ... I'm not sure, probably ten dealers, maybe a dozen. That means that feeling annoyed at "front parking assist" is enough to send a buyer down the street. I'd never thought of it that way, but it makes the dealers much more conservative about the options they pick on their pre-ordered cars. Of course, it's also true that more of us order our cars built to specification in these big markets, so they don't often lose a sale for lack of a particular configuration. As in my case, the bigger dealers here can simply grab a car from elsewhere in the country if you don't want to wait.
Very interesting market effect that I never considered. It makes it tougher to set up test drives of the more specialized options that enthusiasts crave. For anyone around L.A. interested in that PDCC C4S I test drove, it is in Norwalk at McKenna and has only 16 miles on it. (Gentle ones in my case in terms of the engine, though it has visited three speed bumps without slowing. Ahem.)
The picture I used was a straight C4S because their PDCC car was white and looked confusingly like mine, except for being a coupe:
![](https://dl.dropbox.com/u/74382983/Articles/C4SPDCC.jpg)
Not as good a picture either, but it's a beautiful car in person. Except the black wheels for some, I suppose. I prefer flashier jewelry myself, but of course they swap wheels at big dealers like changing underwear.
The power-assisted steering. Everything has to play together when you get a design that works this well. In that sense, you're right. The digital control of that electrical assist surely was a real help when fine-tuning. On the other hand, digital maps can't be used to bandage a poor analog solution. They are best for removing discontinuities, which I won't bother to explain. The underlying analog design has to be very good in the first place to make the overall result this good.
We would surmise that they use different control maps for the steering on AWD models, along with the maps that control the clutches for torque distribution, but that isn't necessarily the case, and it wouldn't be easy to find out. That's one of those details I'd need to spend money on instruments to determine and Porsche probably treat their own answer as proprietary design information.
Gary
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I'll answer the other questions later today. Gotta go pick up the dog from the vet. She's a little miffed already that I don't let her ride on my natural leather, so I need to be on time.
Gary
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With the obvious out of the way, I think I'd put it like this. Some options have to be in the "ooh, I like that" category before we'll pay for them. Retracting mirrors are just an unwanted complexity if you live in a desert and park in our extra-wide parking places for the disabled. Ditto a whip radio antenna. Others are "that would be nice if it happens to be on the car I want for other reasons." The Burmester was that way for me. I chose this car based on deal-breaker items and between three cars they found that met my criteria, this one had all that essential stuff plus natural leather and Burmester. I grabbed it with a big grin.
If I had the same situation again, and one car was available with PDCC and another without, I'd take the PDCC. That much I can say for sure. Now between a C2S and a C4S...
Well, the litmus test on AWD in our Southern California weather is usually whether you ski or snowboard. Those folks always favor AWD, even though a C2S is very capable in routine snow conditions. Just seems like a good idea I'm sure. For me, that leaves AWD as a difference in dynamics. I enjoyed it. I would put it in the same category as the Burmester. Well worth the money, and even the extra 150 lbs, but just a difference of... let's call it personality. I like both personalities, so I'd be happy with it or without it given a car that met my other criteria. I would test both cars and pick the one that pleased me that afternoon -- probably because its leather just smelled right. But to sound more mature, let's say the overall configuration, including body color and interior options, would be the critical factor.
That is a huge improvement in my state of mind, you understand. I refused to even consider a C4S four years ago and I declined a Turbo S just last November because the handling personality just wasn't 'me'. (Even though the salesman offered to "chip it" for me to gain another umpteen horsepower.
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The mildness of my commitment reflects our climate and my no longer doing snow sports. If I were living in most parts of the country, and certainly in Europe, I'd put the current AWD in my dealbreaker list: a gotta have.
Gary
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Now that the beneficial effects of having digital intelligence dynamically applied to suspension geometry are confirmed emphatically (which I accept as empirical validation given the source), the PDCC issue is resolved. I will forever think of Sport PASM as being just "less squishy".
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Gary, volunteering for empirical validator duty, cuz somebody gotta do it
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In comparing the two pictures of today's cab and the prior version (which was 1986 or later - '86 was first with engine lid mounted brake light) and calling the old one my grandfather's Porsche I am a little offended. I have a 991S Cab coming that was due for final producion last Friday. I also had a 1983 911SC Cab (first in Canada) and a 1986 Carrerra Cab. Both ordered new. Neither were my grandfather's car as he passed away in 1930. I am proud to have had my Porsche models grow and mature (while I've grown I'm seldom accused of being mature) since my first one in 1972 (which interestingly enough cost 1/20th of the new. I must be my grandfather in this situation and this confuses me.
I figured the average buyer of a first new Porsche is in their late thirties to early forties. The anthro types consider a generation to be 15-17 years, and the rest of us usually consider it to be twenty years, so a grandfather of that typical buyer would indeed be about my age. Give or take a senile sigh.
Gary
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... And this is why rennlist is a classy place. Thank You.
PS: I still wish you will have an opportunity to weigh in on the PASM vs no PASM, if for no other reason to give myself an idea of how similar or different my perception / take on it is tha yours. Also like you mentioned your comparison was in a 997S, whereas now you would need a 3.4 to compare against a 3.4 PASM or a 3.8 PASM to get a real idea since the springs by default are firmer in an S (and maybe 3.4 with PASM) than in a base car and the S comes standard with PASM.
PS: I still wish you will have an opportunity to weigh in on the PASM vs no PASM, if for no other reason to give myself an idea of how similar or different my perception / take on it is tha yours. Also like you mentioned your comparison was in a 997S, whereas now you would need a 3.4 to compare against a 3.4 PASM or a 3.8 PASM to get a real idea since the springs by default are firmer in an S (and maybe 3.4 with PASM) than in a base car and the S comes standard with PASM.
I wasn't really unhappy with that 997.1S we drove. It was just that Cindy's stroke made her sensitive to shock loads, and my own back even then wouldn't tolerate them well. The mid-range shock and vibration was too much for us to take, and PASM removed most of that. (Not all. I've explained elsewhere that I had to give up 997's because even with PASM, my reaction to the vibration spectrum had become impossible.)
The new chassis very likely changes all that with the full-analog suspension. It certainly does in the PASM versions, and as I say, digital band-aids really don't work. Digital controls need to be refining a basically sound design or they give themselves away quickly, so it's a safe bet that the analog suspension is very capable. Not to mention that it would be the suspension of choice for anyone looking to modify the car for competition. I don't know how I'd even begin if I was trying to mod a computer-controlled suspension. Or rather, I know what I'd want to do, but odds are good the factory already did all that and cracking their encryption is not a trivial project, and probably not worth it if I only going to tune their parameters slightly. Would there be any market for 'chipping' a PDCC?
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I really will try to find a 3.4 coupe to drive next time I visit my dealer. I'm waiting for a part they ordered, so it won't be long I hope.
Gary
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...... Not to mention that it would be the suspension of choice for anyone looking to modify the car for competition. I don't know how I'd even begin if I was trying to mod a computer-controlled suspension. Or rather, I know what I'd want to do, but odds are good the factory already did all that ...... Gary
He told me he had a preview track session and had changed his order from 7 speed to PDK and added PDCC to Sport PASM. He described Sport Plus performance as being as close to a cup car sequential box that anyone wants in street car, and PDCC as being like having him in the car optimizing the suspension geometry on the fly all the time.
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