Porsche911GTS'16

Ipse - as you may know, I have a GTS with PDCC but no RAS and a Touring with RAS and no PDCC. I honestly don’t know why PDCC is not an option on the GT cars but I will say that, having both features (independent of one another), the RAS is more noticeable in terms of performance gains. I don’t find myself missing PDCC in my Touring but there is no question my GTS’s turning capabilities (which are quite good) feel bloated, mushy and imprecise compared to my Touring. I used to think my GTS had amazing handling. Relative to most cars on the road, it does. But the GT3’s handling blows it away. The reason for this is multifactorial but the RAS no doubt plays a role.

seis-speed

I have posted this video before. I like the summation at the end, it comes down to preference.

OFlow

Thanks for all the interesting perspectives and experiences. We all have our own likes and here is no "wrong" 911, so enjoy your build.

The thing that interested me most about the Sport Auto report, and that has not been picked up on here, is the slalom time difference. Why is this interesting? The only practical differences in the two cars tested are the horsepower, RAS, and PDCC. In this slalom test, we can assume that the engine was not the factor (the lower-powered car won). We can also assume that the RAS played little role as it is mostly active below 50 km/h and above 80 km/h. I have heard reports that it adjusts toe in at all speeds but, according to Porsche's own engineering reports, the RAS likely neither hurt nor helped the C2S in this test. This is interesting because it isolates the difference in the cars to the PDCC. This slalom test is really a quantitative test of whether PDCC helps handling. The answer is that it apparently hurts. Given that PDCC works by first sensing the car's movements and then changing the roll stiffness, it is always reacting and not predicting. It is maybe not surprising that, in a slalom with rapid changes in direction, the system is always a little behind the driver (even if it is just milliseconds).

So if you want to take a recommendation out of the article, leave off the PDCC (which also leaves off the expense-to-replace Lithium-Iron-Phosphate battery also) and keep the RAS you like it.

992Sam

that sums it up... it's while some Porsche owners would never trade in their 964 for a 992... metrics be damned.

G650

Agree with all of this except that RAS equipped cars do have lithium ion batteries.

fxz

owned a 991 pdcc and just tested a 992 pdcc
two different systems
I wouldn t re buy the 991 pdcc system whilst the 992 pdcc is really working good

to make a decision you have to test both 992 same version with and without pdcc

ras is a must have for an heavy car I hope new bmw m3 will offer the ras...

OFlow

Thanks for the correction. You are right.

ipse dixit

I think it really depends on what you mean by "handling".

The difference between the GT3 and GTS in terms of handling is more a function of the different sway bars, shocks, springs, control arms, steering rack, lighter weight, and lets not forget the sticky Cup 2 tires, etc than the presence of RAS, or absence of it. Yes, RAS will make a difference, but to pin it down on RAS as a significant contributing factor I think would be misplaced as there are a confluence of other variables that make a GT car a better "handling" car than the a regular 911 (notably the suspension setup and control arms).

Also the "bloated" feel you mention in the GTS probably has less to do with the absence of RAS and more to do with the difference in steering software between a regular 911 and a GT version of the 911.

As to why the PDCC is not even an available option on the GT cars comes down to the interplay of two things: (1) weight and (2) insignificant performance gains.

fxz

apples to oranges
991 pdcc is different than 992 pdcc

Golfster

https://rennlist.com/forums/991/1077...t-is-pdcc.html

https://rennlist.com/forums/991/1041...the-track.html

https://rennlist.com/forums/991/1157...-pick-one.html

https://rennlist.com/forums/992/1133...n-992-a-2.html

https://rennlist.com/forums/992/1164...e-quality.html

https://rennlist.com/forums/991/911394-pdcc-poll-2.html

https://rennlist.com/forums/991-turb...-not-pdcc.html

https://rennlist.com/forums/991-turb...-in-turbo.html

https://rennlist.com/forums/991/9988...yes-or-no.html

https://rennlist.com/forums/991/6712...yes-or-no.html

https://rennlist.com/forums/991/825877-pdcc-option.html

https://rennlist.com/forums/991/6787...cc-or-not.html

https://rennlist.com/forums/991/8157...-question.html

https://rennlist.com/forums/991/8279...c-failure.html

https://rennlist.com/forums/991/1067...rga-4-gts.html

https://rennlist.com/forums/991/7227...rera-4s-2.html

https://rennlist.com/forums/991/850304-pdcc.html

https://rennlist.com/forums/991/7467...installed.html

https://rennlist.com/forums/991/6817...m-or-both.html

https://rennlist.com/forums/991/1062...c-991-a-2.html

https://rennlist.com/forums/991/8372...parison-2.html

https://rennlist.com/forums/991/7131...zkiller-3.html


It can be difficult to find opinions on PDCC. Here are a few specifically for 911's.

uthatcher

I'm new here so hello everyone. I have a thought on the PDCC though...everyone seems to view it as only a performance enhancer on the speed or cornering capacity issue. But from my understanding it also enables a better ride in normal driving by some measure of decoupling the sway bar. And then "tightening" of it up for spirited driving. That seems to make sense to me and would also explain it's absence on GT cars...I would assume daily driving comfort is much less priority for a GT.

I have a 992 C4S with RAS and PDCC but I'm unbiased because I bought it out of dealer stock and did not drive a non PDCC car with RAS. I do feel like this car is a considerable improvement in overall ride and handling vs. a 991 TTS, 991.2 TTS, 991 cab, and 991.2 Targa I had previously. I find the new car to quite a lot more fun to drive. I have not had any GT cars, but I did have a 570S McLaren that still stands as the most lively car to drive that I've had. However, the 992 transmission and PCCB's are the best I've ever used.

apias

Yes, if all your driving consists of slaloms, then it may be the case that not having PDCC will improve performance. The slalom test is really a test of whether PDCC helps or hurts performance in a slalom test. It's not a test of whether it helps or hurts performance and handling in all other circumstances. To put this in terms of a track that everyone is probably familiar with (assuming everyone watches F1), the slalom test predicts that not having PDCC at Suzuka will perhaps help performance in Sector 1 (through the Esses), but it doesn't speak at all to expected performance in Sector 2 (Degner, Hairpin, Spoon). And whether PDCC helps or hurts in Sector 3 (130R, Casio) is ambiguous at best: maybe PDCC hurts in the chicane (Casio), although that's much lower speed than the Esses and you can use the curbs more, but the slalom test again tells us nothing about expected performance through 130R.

In short, looking at a single specific test result won't tell you if a feature is desirable or not overall.

6sigma

I see RAS sort of like PDK - it makes the car faster around a track (why both are standard on the RS cars) and also easier to drive/park. But just the same as why some prefer a slower manual transmission for the feel and engagement, a non-RAS car provides a different, some say more traditional, feel around the bends. PDK and RAS are objectively 'better' but manual non-RAS cars might be subjectively better depending on what you are looking for.

992Sam

literally the truest and smartest post in this thread or any thread recently that I've read... so much of this stuff is a blur of the subjective and the objective..

GrantG

Agree. Stiff swaybars make things like railroad tracks quite rough. Being able to decouple them for these events makes for a much smoother ride. But having permanently stiff swaybars (like on GT cars), gives all the performance, more reliability, and less weight than PDCC, at the expense of a little comfort on rough roads. GT swaybars are also adjustable by providing multiple holes for connection of the drop links, allowing customization of the understeer/oversteer balance.