mwest

I recently acquired an 09 Cayman S, PDK, Sport Chronos.
Plan is to keep it stock (no race seats, harnesses, roll bar, cage etc) and only upgrade tires and pads for track use.
I never time myself and not looking to eek out every 10th of a second. Out there just to have fun.
I'm an instructor and do about 35-40 track days per year.
My primary track car is a modified Z06 that I no longer trailer, I drive it to and hopefully from the track. And I still have my original track car which is a 1.6 Spec Miata that I do trailer when I use it.
I got the Cayman S because I like the car and the look of it and want to do track days and enjoy it on the streets. If I like it more then the Vette, I'd possibly sell the Vette.
But, I've not gotten used to no 3rd pedal.
I bought the car a few weeks ago in Fl and drove it home 15 hrs straight in non stop rain from the time I left Fl till I got to my driveway in NJ.
It gave me a chance to get comfortable with the car but the conditions did not permit me to fully utilize the Sport + mode.
And I've still not been able to fully utilize the Sport + mode on the streets either. We all know it's almost impossible to duplicate tack conditions on the streets and still keep your license.
My question is, what do I need to know about driving a PDK on the track.
Do I just put it in drive and sit back and relax?
I've read all the stuff about how efficient the PDK is but I'd like to hear from you guys that track a PDK and are their any nuances I need to be aware of?
Thanks

RichFL

You're probably ok in NJ, but my 2011 Cayman S PDK crapped out due to too many days on the track in the hot weather here in FL. I had the 3rd radiator but it didn't provide enough cooling to the transmission. If you have any questions you might want to talk with John Tecce at BGB Motorsports in Ormond Beach, FL. Other than that, it's a great car. You might want to consider a different alignment for use on the track to remove some of the under steer.

Frank 993 C4S

Leave it in Sport Plus and let the car do the shifting on the track.

ExMB

One thing you will find is insufficient cooling to the brakes, especially the rears (where the nannies will act). Regarding the PDK cooling, it helps a little if you overfill it.

matttheboatman

Yes, the PDK in auto mode will give you the fastest lap time. It might bother you in a slow corner that the car may momentary downshift too far. If it does bother you, you can take a hybrid approach and control the shifts at certain corners on the track to avoid the computer from upshifting on track out. Whenever I see an experienced driver running a PDK he almost always manually shifts. And, it is almost always slower. Your call.

Be aware that left foot braking may confuse the computer (meaning if you simultaneous application of brakes and throttle) - it is my sense that in hard braking the PDK downshifts in such a manner that it uses engine braking as part of the slowing process.

Getting the alignment correct with rear toe out will be important for rear end stability when under heavy braking.

Many of the racers installed the 3rd radiator kit, added brake duct cooling, and PDK cooler.

My last transition was from a Cayman to a heavier, high horsepower Jag, where I had to shed some habits learned on the Cayman. Going in the other direction - I would guess your challenge will be to overcome the Cayman's tendency to understeer, and getting back on the throttle way earlier (slow in, fast out). And, trusting the Cayman can carry A LOT more speed through high speed turns.

mwest

Guys, thanks for the feedback.
Rich sorry to hear of your issues with car running hot. When you say crapped out, how crapped out are you talking? Like, OK-I now have a giant door stop?
Did you ever solve the running hot issue?
Unfortunately running too hot is an all too common problem on the track.

ExMB, re: PDK, when you say overfill it, what are you specifically referring to?
The trans fluid or coolant?
I'm not at all yet familiar with the subtleties of maintaining this car this car nor how the track will effect it.
My Vette and Miata I know pretty much inside out, but this thing is completely foreign to me.

One of the reasons I went with the Cayman for the track is because one of my buddies is a Master Porsche Tech. He's not a racer but he's a terrific tech. And the other is because a shop opened recently less then 2 miles from my house the guy that owns it is a former racer and Porsche Racing Crew Chief as well as Indy cars.
He made some changes to my Vette suspension set up and I was amazed at how much better and faster the car cornered. As I mentioned I don't time myself but I had a few guys come over to me in the paddock at WGI and asked what got into me. I asked what do you mean, they said I was a lot quicker getting in/put of the corners and they were not able to stay with me.

I'll definitely mention the PDK and brake cooling issues to them and see what they can suggest.
Thanks

ExMB

What helped me on my old CR was to jack up the driver's side as far as I could, Locate the PDK fill port and add enough fluid to the point that it leaked out. This allowed me to run another session prior to it overheating in 100 degree OAT weather. This was in addition to the differential cooler that was added due to the OEM diffy.

A lot of it will depend on how hard you run.

EDIT:
Note that the temp gauge in the car functions like an idiot light and NOT like a true gauge.

dgrobs

^^+1^^

OP:
You're gonna love this car on the track. I have had very little issue with anything going wrong on track, and I'm putting in more than just a few track days on my 14 981S each season. Incredibly reliable. Have fun...

RichFL

mwest -- some of the gears stopped engaging which required a transmission replacement.

Inrev

usctrojanGT3

I got the Olson Motorsports front bumper radiator ducts and never had a problem with my Cayman S overheating.

badabing

I am in NJ and I have been tracking a 987.2 CS PDK for 3 years. Car has around 80 track days.

Here are my basic recommendations;

Oil - Mobil 1 0W-40. Change every 3 events (with filter). Cheap and sold everywhere. Supported by Blackstone analysis.

Brakes - Pagid RS-29 pads F/R.

Rotors OEM (or equivalent) from FCP Euro for free replacement. (Save the rotors on your car now so you have a set to return after your first purchase.)

GT3 brake ducts in front. Cheap

Castrol SRF brake fluid. Don't waste time/money on RBF600.

GT3 or PCCB MC and brake booster.

Titanium brake pad shields from Girodisc

Suspension - GT3 LCA front and rear or equivalent (Tarrett RSS etc)

Adjustable rear toe arms with bumpsteer.

An alignment by a shop who knows these cars and how to dial out the sometimes wicked rear sway on threshold braking.

Bolt in cage - Hergesheimer (or rebranded)

Seats Euro GT3 or Recaro Pole Position. OMP WRC-R (what I have) restrict ingress and egress too much. Seat sliders from early 2000's Audi TT are the same as the oem Porsche ones for a lot less money.

Harnesses - Schroth Profi 2X2 (with HANS)

Exhaust - check your header bolt tightness at every tech inspection. Known to come loose.

PDK - so when a had a ppi done on my car, before purchase, they found a leak and replaced it under warranty. So I effectively got the car with a new trans.

Tracked the car for 2 years including driving to / from all tracks. Performed flawlessly. Never touched it.

In the off season after my second year I decided to have the pdk fluid changed and install a Guard LSD.

My trans failed on my second track day (a cool day in April) manifesting itself my a limp mode message (transmission emergency run) and dropping reverse gear.

Took it back to the shop several times for recalibration but problem always quickly returned.

I was able to run in track most of the season as all forward gears worked, I just avoided putting it in reverse (trailering to the track at this point).

Eventually it started going into limp mode while on track after 6 - 8 laps.

I am out of warranty and still trying to find a solution that doesn't require me to fork out for a whole new pdk.

As a result of my experiences my recommendation is as follows;

Have the pdk serviced at least once a season. By the dealer. Flemington Porsche has a reasonable price for this service with pca discount.

Do not install an aftermarket lsd in the trans unless the trans was originally equipped with lsd/ptv. Guard has since pulled their lsd for non lsd pdk trans from the market.

Install the LN engineering trans cooler which water cools both the pdk and diff fluid.

I have the bgb kit which is an air to oil cooler for the diff only. I think the LN is a better, more effective solution.

Consider buying an aftermarket warranty which will cover the trans in case of failure.

If you would like to chat more on any specific topic or come check out my car and see what I have done, you are more than welcome. I have DIY'd most of the mods. Send me a PM

GTgears

I was given a heads up about this thread and asked to comment by one of our dealers because it contains inaccurate information about what my company offers in the way of products. There are two PDK gearboxes, and as a result of that there are two different size LSDs available out there. When Porsche released the PDK, they didn't believe that they would ever need a mechanical LSD in the cars, and didn't make allowances for it. I will call this the "small" gearbox. Then a couple of years later, they changed their minds and created PTV, which includes a mechanical LSD as part of that package. I believe that is included on cars with Sport Chrono. It required Porsche/ZF make a new casting and a larger gearbox to fit the LSD in there. I will call that the "large" gearbox. This is the same gearbox that they use on the GT4 Clubsport racecars.

Here's a thread about PDK failures for people to read if they want to track these cars. It's very informative of what you are in for:

https://rennlist.com/forums/racing-a...e-track-3.html

Guard makes a replacement LSD for the large gearbox. While we have seen the gearbox itself to be quite reliable, the LSD itself is not. They use these strange clutches that have the friction discs adhered to the plates. The discs come off and stack up in a pile, and the LSD doesn't work properly. I've heard a rumour that they are changing this on the Clubsport/MR racecars, but the last one I had apart (about a year ago) still had these clutches in it.


We make an LSD to replace these.

Then there's the small gearbox with an open diff. We did make a product to replace these open diffs. We called it the "baby diff". We have dropped this product from our assortment. We do not consider that gearbox to be reliable, or "motorsports grade". We make parts for racecars. While we sell a ton of parts for street tuner and DE usage, it's not our market. When we started hearing about the common failures of these gearboxes, we became concerned. And then people started trying to blame our product for the failure. We were selling on average a dozen of these baby diffs a year. For comparison, we sell about 100 Cayman 6spd and 2-3 dozen big PDK LSDs a year. We are seeing WAY more than a dozen open diff PDK gearbox failures a year. And if you read that thread I linked, you will see quite a few posters having failures who have no LSD at all. It is our belief that the LSD is not causal. But we don't want to be anywhere near the failures, and since it's not an actual racing application, when we sold out of baby diffs earlier this year, we decided not to make them again. At some point BGB or another shop may figure out a way to make the gearboxes reliable. When they do we will come back into the market. But as long as they are failing with some regularity, we want nothing to do with it. It's not worth the brain damage for less than $25k in sales annually.

I repeat, we will continue to make the big replacement LSD. Anyone with a factory LSD that fails, we can replace it. Also, the big LSD fits in the 7spd manual 991 Carrera gearbox as well. I hope this clear things up. Please feel free to ask any questions if you have them.

Regards,

Matt Monson
Guard Transmission llc

mlct

Thanks Matt. One question, how can one tell if a car has the "big" PDK and not the "small"? Perhaps by year?

okie981

Matt,
When these "small" PDK gearbox failures occur, is there a more common failure mode? IOW, does the differential self destruct or is it the gearbox gears that fail? Parts exploding or burning up, or?

Thanks