991Dreamer

Getting closer to my build thanks to all of your advice/tips/etc. If I do go with the C2 I'm wondering about PASM. In the August Excellence issue, Pete Stout writes about driving a 987 w/o PASM and feeling that something was "amiss". My assumption is that he was pushing the car hard. Since I plan to use my 991 as a dd and not track it or even drive spriritly (is that a word?) alot, I'm wondering if I would even notice the absence of PASM or gain much with it. Below are my planned builds at the moment. Any thoughts?

Base 991 (with 19" wheels)
White (thanks docmaolone for the pics)
Black interior (keeping white dials for contrast)
PDK
PSE
Multi function steering wheel

OR

Carrera S
White
Black interior
PDK
Sport Design Wheels
Multi function steering wheel

chuck911

The purpose of a lot of these things - PASM, PDDC, Sport Chrono, even PSE to some extent I guess - is not to make the car more high performance, but to make a very high performance car eminently comfortable for daily driving. Think of it this way. Were it not for PASM, Porsche would have to select a combination of spring rates and shock damping that balances very high performance with the need for the driver to be able to survive driving the car on normal (ie, beat up) public roads. A very stiff yet survivable experience. PASM allows Porsche to use much more compliant shock values when able, yet instantly adjust to very firm values when needed. So it may not seem intuitive but you will almost certainly love PASM even if you never drive very hard at all. Seek out Gary Sims superb comments, a guy with back problems could hardly stand the car without PASM.

991Dreamer

Thanks Chuck. I will look for Gary's entry. Also, do you or anyone else know how the two PASM settings relate to the Base settings w/o PASM. It looks like the BASE setting is somewhere between PASM but I'm not sure on this.

WCE

Base suspension is marginally softer than PASM in normal mode. If you aren't going to the track and don't mind the 10mm extra height, this is all the 911 you need.
When I tracked my non-PASM Carrera, I could occasionally detect some instances under high speed trail brake cornering when the car didn't feel as settled as I expected. IMO PASM probably would have cured this by firming the shocks up a bit + the higher rate springs that are part of the package.

docmalone

I think you are correct, with "usual every day driving" I don't think you will notice a difference about PSAM or no. Honestly, both cars (base versus S) are so good and both so improved from the 997 version that I wonder if any of us could even tell the difference if they weren't labelled!

simsgw

I did not find that to be the case with the 997, though they could have changed their decisions with the 991. Previously, the base model analog suspension was stiffer, less compliant, than PASM in touring mode. It's hard to see how you could build an effective sports car that was softer all the time than PASM in that mode. The only reason it works with digital control is the car can switch to very tautly-controlled suspension mode in a fraction of a second. At it's most 'alert' control map, a PASM car handles like it has race suspension, and I certainly don't want to drive around public roads that way.

The real benefit of PASM is that rapid adaptability that responds to your control actions by invoking chassis behavior that matches your intent. Forgive me when I say it reminds me of that company motto in "L.A. Confidential": "Whatever you desire."

Maybe we could get a little chrome Fleur de Lis symbol on the flank of PASM-equipped cars.

Gary

chuck911

The first part, that the base 991 is much improved over the 997, is right on. Second part, about being able to tell the difference, not so much. The PASM cars I have driven were so much more poised at all times even just driving around town that I have a hard time believing I wouldn't be able to tell them apart, buttons or no buttons. Equally sure there are a lot of experienced drivers here who would have no problem either. This is your first Porsche so of course it is so much better than anything you're used to, its like seeing a diamond for the first time when all you've seen before are agates. How can anyone tell these diamonds apart? Live with your gem, become accustomed to it, and in time believe me you'll understand.

991Dreamer

Chuck comes real close I think. My last 911 was 25 years ago and I know the 991 is light years ahead of that SC I had. When I test drove the Base and S 2009 models a couple of years ago I couldn't even tell the low end torque apart from the two let alone anything else. I'm trying as best I can not to have remorse over my choice once I have it and am able to tell the difference due to time in it. I haven't gone out of town yet to a dealer that has both models but can you really tell much of a difference in a 30 min test drive? My guess is no. But of course that seems to be the next step I need to take.

rpilot

Give us your thoughts after your PASM and non-PASM test drive...

docmalone

Well, I am no expert on any of the engineering "stuff" and honestly I drive like an old granny most of the time.

I wish I knew how much of what I love about my new 991 S is due to "S" options versus 997 to 991 differences. Probably a combination. I didn't ever have this "Oh my God this car is awesome" moment with my 997. I am having that moment every day now.
All I can say is DAD GUM this car makes me happy!!!!!

991Dreamer

Base Carrera-$82,100. Carrera S-$96,400. Being DAD GUM happy with your car-priceless!

chuck911

You know Gary, I know nothing of the mapping used, but I think your digital control comment explains my "poised at all times" feeling. If the mapping is immediate and continuous enough then it could be adjusting damping even while doing things like say driving over railroad tracks, allowing compliance to absorb the rail impacts while damping the bigger up/down motion going over the built-up section going over the tracks. Common sense would say it has to be that fast and continuous, else how could it be responsive enough to driving inputs to remain so subtly out of notice? Its just hard to believe they've made something able to respond so quickly, effectively and unobtrusively!

rpilot

I think this issue lies at the crux of what we noobes are struggling with when trying to make up our minds between PASM and no PASM, PTV or no PTV, DEM or no DEM cars. Most favorable opinions I have heard about these options come from those going from different flavors of 997 to a 991S.

The opinions that say that the 991 is just fine without these options for a DD are generally from those speaking after short test drives in both or after some time on a track with both instead of long term ownership.

According to rnl or sprouezza or galion and some others (who has owned both a PASM and non-PASM 991 with 20s in both case..) there is no signficant difference as a daily driver. Perhaps my biases want me to agree with them.

On the other hand, Chuck911 and Gary seem like veterans of porsche land so their opinions cannot be easily dismissed. Although Gary's PASM vs non-PASM thoughts were from 2007 in a 997, not a 991.

technovc probably took the easiest (and imo the smartest route): "the car I test drove had pasm and I liked it and I added it on my car"

So, how much of the 991S you love is really the "S" or really the fact that the 991 is inherently much better than the 997 or the 996 or the 993 you were driving previously, especially in terms of driver comfort, since most performance numbers are easily quantifiable.

*#$$#%&&!!

991Dreamer

Great post rpilot. Is there substantial agreement with it? Comments on it would be most helpful to those of us considering these options. Thanks.

simsgw

That's an excellent example. And one of their own test scenarios I'm sure. The speed of a computer compared to normal physical processes is difficult for intuition to grasp. The real limiting factor is how quickly the suspension elements can respond to computer commands. I've tested that railroad crossing effect myself and I agree with you. Even in sport-plus mode, the suspension backs off long enough to absorb the shock loads and then reverts to taut control before the car travels even ten feet. We did this on fighter aircraft 35 years ago, so it isn't science fiction anymore but it sure is a pleasure to see the technology applied to such peaceful pursuits.

I did say 'peaceful', not 'mild' didn't I? (He asked while switching to Sports Plus mode with PSE enabled.)

Gary