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Hi guys. Page 10 of this magazine has an article written by Jared Cullop. He is testing a highly equipped 991S PDK. He writes that after 300 miles on the car, he figured out that PDCC was reducing his fun. He missed the compression-rebound of the suspension.

I was thinking of including this option (PDCC) in my build, because of all the hype and marketing that have been published about it. This article makes sense to me and now I may not order PDCC.

Thoughts?

aamersa

This is an issue of debate that has been done a few times on various forums. There are differing points of view. You will ultimately have to make this call on your own as the opinions are very varied. Personally I have never missed or felt need for PDCC even in highly spirited urban driving. But then I have not driven a car with PDCC to know if it enhances driving experience or kills the buzz.

chuckbdc

PDCC increases cornering performance. I suppose it may be possible to get used to it. But I disliked it on test drives for the exact reasons that were in Excellence even though I fully appreciate what it is capable of doing.

I had a chance to flog a Panarema GTS with it at the track and it really fits with the ubersedan personna a whole lot better than the 991.

I have PASM Sport and, compared to PASM, it handles better and feels more "sporty", without the ride quality penalty typical of aftermarket short springs and stiff sway bars.

Alan Smithee

It's personal preference. If you enjoy man/machine interaction, active anti-roll systems take away all direct suspension communication and replace it with lines of computer code. Makes for more grip by reducing weight transfer, therefore keeping all four tires more evenly loaded, which results in faster lap times. But for some of us, less enjoyment.

Mike in CA

My Cayenne S has PDCC and in an SUV which is almost 1500lb heavier and a foot and a half taller than a 991, it offers some real benefits. But because of the added weight and complexity of the system, and the possibility that it might introduce an artificial feel into the handling of a sports car, I've decided not to order it on the 991 GT3 I'm waiting for.

Alstoy

I agree with prior posts that it is somewhat subjective and individual, like most things. I am going for as bum-basic as possible. Cheers.

TSpyder

+1. I test drove the 991 with and w/o PDCC. Any difference I felt was not necessarily for the better, so I passed on this option. Having said that, I really like active roll stabilization on my 650, a far heavier car with a higher COG as Mike points out. OTOH, the hydraulically controlled front sway bar was one of the only warranty claims I had during the first 5 yrs of owning the BMW. It ultimately had to be replaced.

Spyder

fbroen

If reducing roll and the "suspension rebound" is buzzkill, then is a car with stiffer traditional rollbars also more boring? And is one with more body roll more fun?

chuckbdc

Totally different mechanically and in terms of feel. As i understand it, a stiffer traditional rollbar is static, so the transients are due to the mass alone. PDDC adjustment is continuous, as thought there was someone competent dialing in spring rates instantaneously to manipulate the mass. Even if that is all wrong, it just feels way different to me, and the SPASM while it gives up some absolute cornering feels mo good to me.

fbroen

It would seem to me that the lower the car and the stiffer the rollbars, the less "feel" there should be from the PDCC. On a car with SPASM with stiffer rollbars to begin with, the less rebound and therefore "feel" of the PDCC?

I don't think the spring rates are dialed with? Rather how "big" the rollbar is at any given time, by actuating its attachment points. I think the other description is closer to the McLaren active suspension?

TSpyder

It's my understanding that cars with PDCC are fitted with "thinner" anti-sway bars, if they have them at all. So, even SPASM cars with PDCC will exhibit PDCC "feel".

It's also worth noting that BMW eschews active roll stabilization on it's M5 and M6, fitting larger diameter anti-sway bars instead. In this instance, BMW has decided that any ride deterioration caused by larger bars, is a better solution for their highest performing cars than hydraulic roll control. Porsche has apparently decided otherwise, or, at least, has left the decision up to the buyer.

Spyder

Rainier_991

I was furtunate to try similar specc'ed cars (both "S") with and without PDCC - both cars with SPASM so please keep that in mind for what I am about to write.
I too, read a few pieces on PDCC but had to find out myself as it is very difficult to judge from disconnected test reports. I do believe that if you take a group of 100 random drivers (any drivers, including those that never have driven a performance car) - you will get a rough 50/50 split in opinions.
No doubt - the PDCC seems to make the ride smoother, like you have softer dampers (that aren't). This does translate to giving a more dead or remote feel to the car. Some will like that, others will not. My most noticable recollection however was the steering. Now, there is a rumor floating around that at some stage the steering has been tweaked - if that is true it is possible that one of the cars (the PDCC) had the "old" and the other the "new". That makes it difficult to be accurate. There may also have been different tyre pressures and of course we know that makes a difference too. Anyway - the non-PDCC definitely felt more connected. The steering wheel does not do anything wild so there is no force in the feedback - but you can feel much more - like there is a damper in the one but not the other (best way I can put it). I cannot comment on the cornering ability at extremes. However, taking "spirited" cornering off track as a measure there is simply no noticable difference in body lean. The non-PDCC car cornering very flat indeed (keep in mind it is a SPASM). At the same time - this is where the difference in steering feel seems the biggest (again subject to what I wrote above).
I have not had the chance of testing completely identical cars in identical conditions back to back (a few days between tests) so everything I wrote here may be different in different circumstances or different on a track.
My very personal opinion is that PDCC is perhaps a better option on a PASM car but perhaps should be left out on a SPASM unless you are into serious track competitons where it may be an advantage - but others are better qualified to comment on that.
This is what I chose in the end for my own build: SPASM, no PDCC and I think for my personal taste - that is the best possible choice.

EDIT: All driving in Sport (not sport+).

Rainier

fbroen

PDCC cars have sway bars. The McLaren system does not.

Edit: McLaren -- is my understanding. The PDCC system for sure has sway bars. The McLaren has active anti-roll suspension vs Porsche active rollbars.

porsche518

I opted out of the PDCC for this reason.

A quick question for you guys, I got the PASM suspension order No 030, there is only one option for pasm on the configurator. Is this the SPASM every one is speaking off, it is confusing since there is talk of PASM vs SPASM and I have only seen one option.

Rainier_991

It appears as "PASM sport suspension (20mm lower)" on the configurator for our neck of the woods.

The main reason for choosing this suspension is not the lower ride (it is only marginaly lower compared to the standard "PASM") but the much stiffer springs and roll bars. This in combination with the PASM gives a nice and comfortable ride with the suspension set in "comfort" but a very nice and firm ride in "full attack" mode. It's firm but not in a way that crunches your spine - just enough to leave you in no doubt that you are in a sports car that has class.

It may not be the ideal choice if you want an everyday driving car and have bad roads - it may be better to get the standard PASM in that case - with or without PDCC.
If at all possible - try and bum a ride on one before you make up your mind.

Rainier