stout

Sorry for the cross post from the 997 forum, but thought you guys would appreciate this, too, as it looks like PDK will be heading into the GT2/GT3 cars, as well. So here goes:

Just drove PDK in Germany. It shreds SMG and is better than DSG, too. Most noticeably when leaving the line, where DSG struggles to figure out when, exactly, to get moving against your throttle input. You get better at it with DSG, but PDK is totally perfect in this regard. Very impressive.

Other good stuff:

-PDK's shifts are superb, both up and down.

-Steering wheel buttons work very well for normal driving, except for polarity. Buttons may look funny in pictures, but they are VERY ergonomic is use. A subtle rocking of either hand gets you that upshift. I just wish it was a downshift instead...but you can read more about that below.

-Default mode very efficient/quiet around town.

-Manual mode is just that, almost entirely, anyway.

-Sport Plus is ridiculously intelligent in picking gears for fast driving.

-Left foot braking is easier than ever, but a lot of great drivers do not use this. I started experimenting with it a couple of years ago, then, I dunno, forgot to keep practicing it. With PDK, I am sure I would develop the skill, because my left foot would get bored...


But the first-gen PDK system is not quite perfect. The niggles:

-Normal mode tries to go to sixth, then seventh as quickly as possible, just as Tip tried to go to fourth, then fifth. Good for emissions and economy, but, sometimes, if you're like me, you think "Hey, maybe I want to run a gear down around town." Maybe it's the air-cooled guy still in me. I dunno. You can switch to Sport or Sport Plus, but the latter, especially, is too aggressive around town, ALWAYS holding second. This is a minor thing, but PDK feels a bit TOO efficient at times in full auto mode. Hard to describe, but I wouldn't have this complaint in an A3 or GTI, if you know what I mean. Again, minor niggle and arguably stupid given environmental reasoning. And at least it shifts quickly enough to not leave you caught out when you need to squirt into a gap, like Tip so often does.

-Push forward for upshifts/pull back for downshifts is counter-intuitive in terms of g forces and other points of reference, from shifter carts to most other cars. Even BMW realized it had it wrong and changed to the "proper" (push forward for downshifts under braking) polarity a few years ago. Even after a day and a half, and I am usually very good at "adjusting" to a given car as a result of driving so many, I still found myself occasionally shifting from fourth to sixth with PDK at the track -- when I wanted second. This wasn't good for my line, and the only way to avoid the issue was to really think about it while trying to, uh, drive. When doing that, I'd rather think about other things like lines, braking points, etc. Even though I'm sure I would "adjust" in time, this is my biggest beef with PDK, however. Even those within Weissach were divided on this, with test drivers and racers wanting the "normal" setup but others wanting the Tip/Cayenne logic. The latter won out. But, if BMW switched, maybe there is hope.

-Upshifts in the Sport Plus mode are hard, harsh, and jolting if you are a mechanically sympathetic driver, and thus disturbing. That said, this criticism faded somewhat when I discussed the issue with an engineer who revealed there is a slight but worthwhile lap time advantage to the hard upshifts (they are not allowed if the car is cornering, by the way) and that the driveline was engineered to deal with the increased torque hit.

-Steering wheel buttons, for serious driving, subtly goad you into keeping your hands at 9 and 3. I am a devout shuffle-steerer, but found myself crossing my arms at the track. Not good for leverage and fine-tuning, and not good in a road car with an airbag behind those wrists. Tall paddles a la Ferrari would be better. Just my opinion. Another solution would be to use the console shifter, but then you lose the advantage of keeping two hands on the wheel at all times...

Overall verdict:

PDK is an INCREDIBLE replacement for Tiptronic. Period. Porsche did a great job with the transmission. It's also a great option for sporting drivers who don't particularly love shifting with a clutch pedal. As for me? I'd like to flirt with PDK a little more than for just a day or two, and will look forward to that. But I'd still order a stick. I'm pretty sure I'd be quicker with PDK in the end, but I'm not a pro racer, probably never will be, and drive for pleasure, not ultimate lap times.

If the above niggles were resolved and if I did a LOT of track days, I might revisit the subject, but giving up the involvement of heel/toe interaction is, for me, a tall order. The good news is that, if that's not an issue for you, you f-i-n-a-l-l-y have a truly SUPERB alternative.

pete

nat3970

Thanks for the writeup. Very informative. May not be the popular view with other GT3 owners, but I for one am hoping PDK is offered in next GT3, whenever it makes its appearance...

Larry Cable

as long as a manual is still an option! - enjoy!

85Gold

Assuming the buttons are electrical it should be easy to reverse the wires and change the way they work.

Peter

nat3970

Its a virtual certainty that manual would still be an option on a car like GT3. To be clear only reason I'm interested in the first place is because I'm willing to forgo the manual clutch experience for the perceived benefits of PDK. I say "perceived" because the excmag reviews is one of the first I've seen on the subject. Hope to have an opportunity to try on regular 911 sometime in near future.

chardonet

Thank you for the excellent write-up.

NJ-GT

Pete, great feedback.

I think Porsche screwed up the gear ratios on the PDK for the 2009 911. Instead of using a close ratio 7-speed, they just added an even longer (Viper/Vette style) 7th gear good for speeds above 250mph.

I agree it's a great substitute for the Tiptronic, but not for the manual transmission yet. Now, if they put the same ratios as the E92 BMW M3 in the next GT3 with PDK, that will be the only transmission choice.

Brian S

I believe the manual would still have to be standard with pdk being optional. PDK is NOT the 6 spd sequential that is used in the cup cars, so we are not getting more of the racing experience by using it especially like you said backwards. I have driven other clutch based autos similar to pdk and parking isn't nearly as easy as you would think. The Merc one actually wouldn't select 3rd gear for me twice and went to neutral under power during a test drive with the salesman in the car, needless to say they didn't sell me an E55 that day.

Then again, street bikes shift backwards from race bikes don't they?

Yargk

If I had PDK...

Step one, put in cup steering wheel with no buttons.

Step two, reverse console shifter so pulling back is shifting up.

Then I'd enjoy my pseudo cup shifter.

dagor6

Street bikes shift intuitively, up is up and down is down. Very nice.

Race bikes use a GP (reverse) pattern which allow you to up shift by pressing down. This is key since getting your foot underneath to shift out of a corner is impossible with the bike leaned all the way over.

In any case, once you drive a sequential you'll never see the point of a non-sequential on a performance car again.

I'm just wondering where our slipper clutches are? Is it impossible to do for a car?

CP

I hope you mean 'speeds above 250 kph'.

CP

stout

Had the same thought and mentioned that, to which one of the engineers thought, then said "But the buttons would no longer read correctly!!!!" Talk about stating the obvious. I guess I was the only one at the table who would rather have that out of order than the shifting itself. Plus, it would be entertaining when I let others drive the car.

The guy didn't answer whether it could be done (I am guessing it's a one way plug), but I was thinking snip-snip would be fair game so passionately do I dislike this setup.

pete

stout

Oh, for the days when you could spec your gearing. Surprised that more tuners don't really market this idea to owners of the modern cars.

And I get your joke about 250 mph. PDK gearing worked pretty well on the road. One thing (the only thing?) BMW got right with the current M5 is the gearing. Too bad the E63 AMG is a far better car of the type, and too bad the M5 manual is a "oh, so you don't believe that SMG is zuperior? OK, here, HERE'S your manual." Only drove the new M3 with a manual, so I can't speak to its ratios...

pete

NJ-GT

No hopes. They (lame Porsche) essentially geared the PDK first 6 gears the same as the manual. 7th gear goes 80 mph at 2,250 rpm. 7th is good for 267 mph, and I was already complaining that my GT3 had long gears by having a 6th capable of 205 mph.

CP

I now see what you mean. Top speed in the 7-speed PDK tranny will NOT be gearing-limited. That's cool.

We only need a Veyron motor and we're all good to go.

CP