GainesvilleGT4

I was really tempted to take the GT4RS to Sebring for a track day yesterday but decided against it until I’ve covered at least 1000 miles of break-in. But, wow, tough day with the PDK on the 981S. My speed at a few corners has risen quite a bit after getting some coaching from their pro racer. He took my car out and confirmed what I was experiencing. In paddle shift mode the PDK will downshift by itself without a pull of the left paddle. This was highly annoying, especially those times when I was a split second from downshifting anyway causing it to cog down 2 gears. This mostly happened in 3rd gear corners where the PDK chose 2nd and a professional racing driver was being overridden by a computer. Any idea if this can be remapped? Did 718s have this issue too? Or should I just give up and trade it in for a MT like we all had in the before-time?

EDIT: Car came originally with the non-sport steering wheel, I upgraded to the sport wheel last year, not sure if this makes a difference.

DIS295

I've only experienced an automatic PDK downshift while in manual mode, when I come to a stop and haven't downshifted. Happened once or twice in 18K miles. Never forcing a downshift that I haven't initiated otherwise. I never use auto mode. 718 GTS.

GainesvilleGT4

That’s definitely a scenario I could see being beneficial, the PDK shifts to 1st gear to stop the engine from stalling when stopped. Good to know your 718 GTS is “normal” in all other moments.

Dr.Bill

Was it in normal mode, sport mode, or sport plus?
I know in sport plus / manual it should not shift without a paddle input. Not sure about normal or sport.

RajuPatel

i am not a PDK guy.. but doesn't the computer learn and then adapt as it learns/

RajuPatel

sorry i misunderstood the situation.. my bad

GainesvilleGT4

It was in Sport Plus mode. That’s what was so bizarre. It was consistently downshifting at the same corners too on every lap. Happened to both me and the pro driver. Gear lever all the way to the left in manual mode.

manifold danger

Never heard of this. I don't have much track time in a PDK car, but I definitely haven't experienced what's described. Manual mode means manual.

Maybe the steering wheel swap futzed with something... very curious to hear if others have experienced similar.

Kitc2246

From my six year track experience with PDK definitely not normal. Sounds like the PDK doesn't know its in manual. Might be something as simple as a microswitch. As we all know Porsche does not support repairs for the PDK. I'd find an indy with a PIWIS to at least check for codes. The replacement steering wheel could have introduced a logic glitch. I'd call Atlspeedwerks to see if you can get some free advice. They did a PDK repair YouTube with PCA. My only issue with the two PDKs I've had is the kick down when I get too aggressive on the throttle. Too cheap to pay for the Cobb PDK tune to eliminate the kick down. Later models turn this off in Sport+.

We are all looking forward to your post when you get the RS to the track.

Putting the original steering wheel back on might be too much trouble, but worth a thought.

Just called Atlspeedwerks and chatted with Brian (in the Youtube), shop manager. He is more than willing to talk. He said they had a customer with a similar situation that happened at the same place on a track. They finally attributed it to the PDK software (flaw) where its not a true 100% manual.

ramans

So I'll chime in and say I've seen this happen. I had a 981 Cayman S PDK non-sport chrono as my track car for the past four years. And even in sport mode, with the shifter set to manual it would downshift byitself, but only if you pushed your foot all the way down on the throttle. The throttle has a slight catch in it at the bottom, you can feel it with your foot, if you don't push through that then it won't shift itself, if you do then it'll shift all by itself down when it thinks it should even in manual mode. It's pretty annoying in my book, but yeah it happens. I'm hoping my new 718 GT4 will not do that.

matttheboatman

Wait a minute. If I read your post correctly, it says that it shifted to 2nd when you thought it should be in 3rd. If you are in auto sports plus mode, this is normal. The transmission is programmed to put the car in the lowest gear possible (even if only for 1 second) until that gear is maxed out.

Placing the shift lever to the far left is supposed to engage manual mode, you have 99% control. The computer will still downshift to a lower gear if leaving it in a higher gear if doing so will bog down the engine - such as when coming to a stop light in 3rd, it will automatically shift to 1st.

Off the subject but related ...on most corners in a PDK Cayman where it can be run in 2nd, it is faster through the corner in 2nd gear. If you and the pro driver were placing the car in 3rd, and the computer allowed it to shift automatically to 2nd, and not overrev, then it is proof you and he were leaving some RPMS on the table. Reasonable. My advice is to adopt the computers' gear of choice in my opinion. Are there scenarious when you want the car in a different gear than max rpms at all times? Yes, but in general, if you (and the pro) allow the computer to max out RPMS in every scenario, including key difference points of downshifts, braking, and mid-corner - I promise you both will be faster in auto IMO.

nineball

agreed. not sure of the differences between 987 vs 981 vs 718 with regard to the PDK but i found in my 718 CS the PDK will "learn" what i do and where i do it on the track, then replicate that each lap (for the same session). for example there is one area at mid-ohio that my 718 always had a hard upshift on the first lap, however it "learned" that area and would correct it for all subsequent laps that session (this is all based on leaving it in "D" and not using the paddles in sport+). additionally if i played with the paddles the PDK would mimic my shift points for the remainder of the session, even if they were not the same as what the PDK would use if left alone.

i typically just shift to D and let it do it's thing. had a couple left shoulder surgeries so i can't make it even a half day at track with a manual. the PDK is faster and smarter than i am so i just let it roll.

late last year i picked up a 987.2 S PDK so i will be able to compare apples to apples this may when i take it to mid-ohio for the first weekend of the year.

GainesvilleGT4

Thanks for reaching out to Brian, I just left a voicemail for him. Got excited when I saw he was in Gainesville, but then saw he’s in GA not FL. That’s OK though because I take the 981CS up to Atlanta a lot and my next trip up is in a few weeks.

GainesvilleGT4

Great info, thanks. This is my first non-manual I’ve ever taken on a track (in 38 years of track days) so it’s definitely a learning curve.

TXshaggy

You should post this over in the 981 forum for better analysis.

It sounds like you hit the PDK Kick-Down switch. Believe the older cars kicked down even in manual.

Think they changed this in 718s to only kick down in D.

718 GT cars don’t have a kick down switch.