Dag Johnsen

Packing my bags, I`ll take one lap for you man :-)

Look at this video, see how the current fastest Porsche, the GT2 RS is catching the slowest one, the base Carrera (me inside, my friend in the GT2 RS) Use HD, camera is not steady so HD helps.
You can spot me at 5.33, the silver Porsche in front of a silver 996 with 590 horsepower, also a friend. GT2 RS catch me at 7.54 and I should have let him pass, but since his wife was in my car (slowing me down) :-) I let him stay behind me through the last turn.
He is almost 30 seconds faster than me, did a 7.16,9 that day when I did my 7.46. Traffic helped me to stay ahead a little, lucky me :-)

Anne

Slowing you down.... Of course by the weight. :-)
I can confirm that it was a great lap by Dag.

I have the 991 S myself and really wish I had the same setup as Dag, that is sportschassis and no PDCC.

Dag Johnsen

Hey Anne!! If you were fat neither me or Kjetil would let you ride along See you soon, safe trip home from NY and hope the rain forcasted is just a joke

Dag Johnsen

Hi :-)

its a base 2012 Carrera 3.4 PDK 350 hp, Sport PASM -20 mm, Sport Chrono Plus, PTV diff, sport seats and 20" wheels. Standard P Zero tires. Official weight 1400 kilos, 15 less than the S. Normal standard brakes, fantastic!¨
No PDCC, scary stuff that system.

The car eating me up, 997 GT2 RS...

Dag Johnsen

Listen to what they say between 8.20 and 8.50 in this video:

Anne

I think you are on to something important here.

I drove a 997 S for 3,5 years. PDK, Sport Chrono Plus. Completely stock, no PSE or sports suspension. I had many laps on Nurburgring and I loved it. I was really confident with the car and I always felt that the car did what I wanted it to, no negative surprises. The only thing I would have liked to change was to have a stiffer chassis and maybe the seats and belts.

When I was getting my 991 S this summer my expectations were really high. I was expecting a faster car with stiffer chassis and a sharper turn in.
On the road and on the autobahn it felt quite nice, I only felt some unstability at very high speed when going over some crests.
But when I came on my first lap on Nurburgring I was quite shocked. The car felt much softer than the 997, and when turning in corners there was something very strange going on and it was coming from the rear, as if the whole car was twitching. But the worst was how unstable the car was over high speed crests like for instance Schwedenkreutz and the crest before the left turn in Kesselchen. Even when I went at a lower speed than with the 997 the car was so unstable that it went all over the place, passengers also commented that. Needless to say my confidence in the car is not very high.
I started out with Sport Plus and hard suspension as I always did with the 997, but since the car was acting the way it did I tried all combinations. On most parts of the track Sport and the softer suspension worked better.

I have PSE on my 991 S, PDK, Sport Chrono, PDCC, Torque Vectoring and 20" wheels. No sports suspension SPASM. (Didn't spec it myself, just bought it out of the shop.)

I am quite sure it is the PDCC that is ****ing up the handling. So if there was a button to turn it off or a software update, and I also could get the SPASM I would definetly have the perfect car. :-)

I also think the 991 GT3 will be a perfect car, even if its not such an allround car as the Carreras. There should be a good chance that they have made different choices. I hope. :-)

CarManDSL

I too have concerns with "twitching".

Have a mid-May build 991S, 3800km driven so far, PDK, Sport Chrono, PDCC, Sport PASM, 20" wheels.

On higher speed highway cloverleaf onramps, really pushing the lateral G's, 90km/h range, the car sometimes has a slight twitching as if the grip was intermittent. Reminded me of a set of Kumho tires I used years ago on my 996. During highway high speed turns, the tires had a twitchy feeling. I attributed this to low tire pressure and corrected the issue with higher tire pressures. (Had been using slightly lower pressures for comfort reasons on 996 Sport chassis.)

With the 991S I automatically assumed the twitching is a tire issue but now reading the forums, I am not so sure. I have not played with tire pressures and repeated the onramp test and unfortunately have not had a chance for any track days with the 991S.

I have not seen any twitching criticism from press tests on this.

What tires were used when the twitching occurred and at what pressures?

Carrera GT

The lower "comfort" setting of tire pressure could be causing PDCC to make bad decisions. I run the tires at the lower pressure because I find the ride quality to be overly harsh (even compared to a GT3 RS, road for road, butt for butt) and yet too compliant on the track.

I never push the car hard enough on the road to challenge PDCC to really earn its keep (if it can at all) but even a sweeping freeway ramp or the winding mountain road (about ten miles of it) are enough to have the 991S with Sport-PASM and PDCC making all kinds of peculiar moves in the rear.

Had the same bad manners appeared in my old 996 GT3, I would have had it on the service hoist and every nut, bolt, bushing, damper, spring, tire, wheel, hub and bearing removed, inspected and replaced until I found the cause of such erratic jolts and dips and hiccups.

I fail to see how the 991S got out of the road driving phase of development with such awkward gaps in its setup. Perhaps they were so preoccupied with bolting all these expensive add-ons onto the price list, they neglected to first bolt them onto a car and go for a nice long drive in the hills. Perhaps too much of the R&D was done on earlier PASM -- or even conventional dampers to remove all the electronic derivatives, to let the engineers and test drivers drive the car, not drive their own software algorithms -- leaving them with insufficient seat time to do anything but a halfway decent job then meet their deadlines.

I can't really just point at PDCC with a bony finger of accusation, because this could be as simple as tires and tire pressure (the two most important actors in the suspension setup.)

Still, I would love to let my finger tap on the mouse to select "conventional spring and damper" instead of the $10K of "options" that go into the 991S suspension ...

Anne

The car was delivered with standard P Zero tires. For these I use the standard pressure as marked in the door, if I remember correct it is 2,2 and 2,7. As soon as the tires get warm I take out air to maintain the same pressure also when warm. With the cup tires I would have taken out quite a bit more.

But I really dont think this is a tire problem...


+1

CarManDSL

Just topped up the pressure to full recommended 36/44 psi. Had been running 32/38 for street use. Will try the on ramp when it is dry again.

So, being that no one has mentioned another brand of 20" tires, other then the stock P Zero's, this leaves this twitching issue unresolved.


Why hasn't this been mentioned in any press revues?

Anne

A good question. But I guess the manufacturers have some kind of power over parts of the press? Dag found something on this when googling before purchasing, more of us should apparantly do a better job checking out before purchasing...

The tires have the corrct marks on them that show that they are approved by Porsche.

Scott997

I believed those numbers until I tested 2010 997.2 GT3 VS my 991S PDK around PBIR.
GT3 on Supersports, 991 on stock pirellis
GT3 just has SRF fluid and PFC pads.

991S 5 seconds lower a lap consistently and I run consistent lap times.

Carrera GT

Which times, the ring time published by Porsche? That's credible and it's just a "pecking order" ordained by the marketing boffins*, not a real or absolute measure.

Did you mean to write "lower" or "slower" ... ?

I've run 991S and 997 GTS side by side and the 991S is quicker in a straight line acceleration from rolling in 1st, both PDK. 991S is as quick in lap times running Pzero versus 997.2S on RA1.

I imagine, with familiarity, you'll find the 991S the quicker of the two -- Porsche just makes 'em that way. Let's see what they do to slot the 991 GT3 in at the RS 3.8 level, just a tad "less" than the RS in some ways, but neatly "more" than the 997.2 GT3 ... it's a bit comical really, especially since these cars are now about a 100 horsepower under of the market and even the 991 Turbo is rumored to be "only" 550 neddies..

The perennial "Porsche is not about highest horsepower" considerations still apply to the 991, but where will we be come the 991.2 GT2 RS ... 700 hp? ... how can Porsche keep the 911 models all neatly pancake stacked under 700 horses? Surely the 500 horse RS 4.0 will be overtaken by the 991.1 RS (presumably at just about 480 horse, give or take interpolation ... or is it extrapolation?** ... of historical increments, model to model.)

Given the 991.1 GT3 appears to be wide body, that's one less difference the RS will boast. At about 15hp delta, give or take a flywheel or a gear ratio, presumably Porsche has concluded upon a different way of making the RS stand above the GT3. Weight? Aero? ... <gulp> ... electronics?

It looks like these are 2014 models (Frankfurter, Sep '13?) so the long range forecasting is a bit foggy/silly. <insert obligatory comment on needing proper steering>

* I hold Porsche marketing in such high regard.
* Maybe the 991.1 or .2 RS will be a bombshell of high horsepower, but given the guestimated 550 hp in the triple turbo 991.1 Turbo, surely the 991.1 RS will be no more than 500 in deference to the (by then) aging memory of the RS 4.0.

arena-RTR

Ok, so he started the lap timer at the end of the first straight, and stopped at the beginning... Nissan did this with their GTR lap "record" ( ) I don't think that's what they normally consider "bridge to gantry"... can anyone else tell me why they aren't timing a full lap?

Carrera GT

Someone here (thread thread or at the GT forum) that it's an acknowledged "standard" segment of the track used by Autocar or autobild magazine and adopted by others when trying to get an apples to aapl's comparison.