The garage is an old coaching house and not designed for modern machines, but yes it does fit, though I need a carpet on the wall to stop me grazing the door.

 

Thanks for the information. A very useful post. There have been some interesting debates about PDCC. I have ordered it and have been hoping someone would post their personal experience. I'm off to Barber in August and will also drive one to find out a bit more about it.

I came across this video which I found interesting:

 

I'll bet its not even going to be an option on GTxx cars.

PDCC is a way to expand the comfort envelope without sacrificing the proportional amount of performance. It's a "comfort" option.

I'm not saying its a bad choice, but make no mistake about it. It was avail on the cayenne ages ago for a reason....

It's additional weight, complexity and most importantly non linear and therefore unpredictable (not something an expert driver just adapts to). For these reasons I'd be surprised to see it on a GT3. BMW never put it on the prior or current (I believe) M5 despite offering it on all 5 series cars....

DRP

 

I agree..an option but not standard.

 

I read that in GB 991S have it standard and there is no choice.

ChuckJ

 

You have a good point, but we will see what porsche decides. If you read back at many past threads where we assume what the next model will or wont have, we are usually way off, but it sounds good and is fun to predict.

Might be

No, not standard. Cost around $3k as an option for the 991S. Almost nothing is standard on these cars, thats why we usually spend 20k on just options.

 

I don't follow. Preventing body roll (up to .85g) is certainly a performance enhancer to me -- basic physics. Moreover, in real world spirited driving, having a more compliant suspension in a straight line is not only more comfortable but also allows for greater speed and acceleration. In my Targa, there was always 10% of me that thought I was going to hit a pothole, bump or rut too hard and unsettle/damage the car... and that caused me to slow down. 991S with PDCC is much better in that regard.

Re unpredictability, IMO that's only an issue if one is not smooth.

 

Agree with you.
I think it's somewhat simplistic to label PDCC as being a "comfort" option. Reducing body roll has been a target of sports car manufacturers for ages. There is a direct correlation between body roll and performance. How can increased body roll be better for performance or comfort?

 

Its complicated no doubt, hence all the debate over PDCC. It's a comfort option b/c it decouples or loosens the anti sway bars in a straight line - and it allows Porsche to use slightly softer springs, since reducing roll is no longer on their to-do list (I'm not 100% sure they do use softer springs with PDCC, but other manufacturers do?)

A cup car will have very little roll but a terrible ride. Its not hard for a manufacturer to reduce roll. Its hard to reduce roll and preserve the ride. A suspension such as PDCC that doesn't roll much will transfer more g force into the driver giving the impression of greater cornering ability. Actually, a slightly softer setup with more roll will generate the fastest corner speed as the progressive deliberate weight transfer allows the tire to reach its highest potential grip. This is why race cars loosen their suspensions in the rain. Fast transitions from side to side (slalom) and the ability to place the car (clip apexes) is where roll resistant suspensions like PDCC excell - not in outright grip. So PDCC is great for DEs but won't be on the RSR race car anytime soon.

As for the nit pick enthusiast - the ability to predict how a car will behave at the limit allows for confidence. The PDCC will break away relatively abruptly once the tire's mechanical grip is exceeded and that probably isn't preferable to a well tuned sorted out traditional suspension set up if your really at 10/10ths.

I personally don't think PDCC is a bad thing at all on a 911, but it does have some slight drawbacks depending on your own preference and how you use your car.

Enjoy your ride,
DRP

 

I think that should settle it for most of us. I am taking my car to DE's and wish I had PDCC. I have already replaced my springs and will do aftermarket suspension upgrades to corner flat and clip apexes like DrSpeed explains, but I will not have the same level of comfort for my daily drive...
It may be fair to say that if you are not a 'racer' (in which case you would not have a 991S anyhow) but an enthusiast, the PDCC is a nice option for performance AND comfort.

Have fun, with of without PDCC!

 

I would agree. If you think about it PASM was and still is billed as a a so called "performance option", and yet most people simply leave it in normal mode most of the time due to it being a bit harsh for most street driving in sport mode. Even a good amount of heavy track users leave it in normal mode for the same reason. So what is it mainly used for then?,....comfort or performance? I'd say mainly comfort. I loved my previous Cayman S without PASM and 18" wheels, I often ran rings around all the guys with so called loaded up cars complete with 19"s, PASM, etc. I almost wish there was a PASM delete on the 991S. Just more complexity and expense. I wonder why Porsche doesn't even offer it on the best handling Cayman to date, the R . If it's so great for performance, you think they would offer it on the Cayman R, right? Ahhhh, most people want a little more comfort than an R can offer.

Same for PDCC as a car will spend about 95% of it's time in a straight or nearly a straight line, so what's the most benefit then of PDCC?....a little softer ride which it does deliver.

Since it is really not new technology why doesn't Audi, BMW, Ferrari, Lambo and others use it on their top performing cars? All of them have fantastic handling cars without such an item, and have just as many great engineers as does Porsche.

It's a great idea and I do greatly believe in the concept, but for now it's just a little immature and gimmicky for me to spend the money on. Give me something I can really enjoy most if not all of the time for my money.

 

I couldn't find any dimensions on the sway bars in the Tech Manual but I did find spring rates. They are:
Front Suspension
Basic Carrera- 24 N/mm
PASM- 28 N/mm
PASM sport chassis- 33 N/mm

Rear Suspension Strut:
basic- 48 N/mm
PASM-62 N/mm
PASM sports chassis 108 N/mm

ChuckJ
PS I also found that PDCC is turned with PASM. So for those with PASM that don't travel with PASM normally turned on you will not get the benefits of PDCC.

 

Not true, Chuck. PASM is always "on" and so is PDCC. They simply have different operating modes. In the case of PASM it is Normal or Sport, both of which are active algorithms. With PDCC there appear to be three, Normal, Sport and Sport+ triggered either by the selection of Sport+ mode using SC+ (source: 991 brochure), or as a result of the connection between PASM and PDCC as described here (source 991 iManual): "When you select a chassis setup in Porsche Active Suspension Management (PASM) the PDCC system automatically activates the corresponding on-road driving programme". Be assured though that both are always active.

 

I'm not 100% sure but i think McLaren use a technologie like the PDCC on their MP4 12C, and maybe its like the electromagnetic steering wheel, some have cracked it, and some dont (audi!).

 

Here's an interesting article with pictures that I came across - apologies if its a repost:

Edmunds Insideline - Suspension Walkaround: 2012 Porsche 911 Carrera S

"...The stabilizer bar link (green) is hydraulic, as is its opposite number on the other side of the car. A central computer looks at body height sensors, steering angle and a host of other factors to determine how to make them behave.

On straight roads they can go limp to essentially remove the stabilizer bar from the picture for a smooth ride. In corners they can be made to "overdrive" what the stabilizer bar could otherwise do on its own to utterly eliminate body roll. Or the computer can dial in any amount of roll stiffness in between, and it can change its mind in real time as road conditions or driver inputs fluctuate.

Porsche calls this Porsche Dynamic Chassis Control (PDCC) and it's the first time they've fit it to a 911-series vehicle. Whatever you call it, it flat works. This very car pulled 1.04 g on our skidpad, and some of the credit has to be put down to the way this system can make use of all four tires instead of leaning heavily on the outside ones.

You could theoretically achieve the same skidpad prowess with a pair of very big stabilizer bars, but then the car would ride like Grade A dog doo. Conversely, a hydraulic anti-roll system such as this doesn't need a physical stabilizer in between the left and right struts at all, but in that case there'd be no fail-safe if the system developed a fault."