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Flat shift and fishtailing in the GT3

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Old 01-07-2024, 09:50 PM
  #16  
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Originally Posted by jscott82
wow... what type of syncronizer is it using? Even dog-ring would need lift wouldn't it?
Nope, more complicated than that. No synchros required. The gear request command, coupled with throttle opening and engine speed, disengages the engaged gear and nearly seamlessly locks in the next pre-engaged gear (odd-even, one each clutch).

The next gear to be selected is already pre-engaged using one of the two dual-clutches, all electronically controlled by a GCU.

The entire operation, when you are asking the maximum like the OP was, takes between 50-60 milliseconds. Barely perceptible.

Jeez, I remember in the early days where these things took three to four times as long to do that...
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Old 01-07-2024, 09:57 PM
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The tech is sick...

https://frazerpart.com/blogs/technic...es/porsche-pdk
Old 01-07-2024, 10:06 PM
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The double clutch input shaft is super trick. The crazy part is it goes back to the 956!

To the OP - hit up an autocross, DE, Porsche Experience, or similar to build some skills if you are going to drive that spirited. You have a very high performance car.
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Old 01-07-2024, 10:07 PM
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PDK is definitely flat shift, but are we talking flat shifting a manual?

I really haven't looked at the new cars since the 991 first came out.
Old 01-07-2024, 10:20 PM
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With the combination of the lighter flywheel and the lighter clutch pedal pressure (in the 992 GT3 Touring), they do hype it as possible to no-lift shift it. There are some electronic high jinks at work to smooth it out and prevent overrev if you miss it, but that’s what I’ve heard.
Old 01-07-2024, 10:27 PM
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From an owner:

Just as the automatic rev matching makes for a smoother downshift than a human can achieve, the no-lift shift does the same for upshifts (computer perfectly matches the revs to the next gear). It’s particularly smooth at less than full throttle.

The nice thing about the Manual is you can do it all yourself or let the computer do it - very flexible
Old 01-07-2024, 10:31 PM
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The ECM and GCU in the six-speed evidently match revs up and down. Going up allows part-throttle and full throttle flat shifts, but there are other reports that the full throttle flat shifts in the lowest gears can get exciting! Very sophisticated electronics is how they do it, with a combination of varying engine load using fuel and ignition cut so fast you don’t even notice. Spectacular.
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Old 01-08-2024, 06:38 AM
  #23  
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Does his 992 GT3 Touring have the manual or the PDK? I have not seen text saying it is one or the other.....so assuming it is a PDK may be incorrect.

If it is a PDK, of course it flat shifts.....
Old 01-08-2024, 09:00 AM
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Are we talking about the No Lift Shift? That is a feature in the last 2 or 3 generations of manual transmission GT3s. You still have to clutch, you just don't have to lift the throttle.
Otherwise we'd have to be talking about a PDK.
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Old 01-08-2024, 10:38 AM
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Originally Posted by winders
Does his 992 GT3 Touring have the manual or the PDK? I have not seen text saying it is one or the other.....so assuming it is a PDK may be incorrect.

If it is a PDK, of course it flat shifts.....
​​​​​​​It is a manual
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Old 01-08-2024, 11:56 AM
  #26  
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Originally Posted by based_1
It is a manual
You might want to look in the 992 GT3 sub forum, I think there has been some discussion on the no-lift feature.
Another thought is that you said you were in Sport mode and I believe Sport allows a bit more tire spin and slip before ESC/TC acts. If you can safely try it in normal mode the car may act differently

​​​​​​​Enjoy the car!
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Old 01-08-2024, 01:06 PM
  #27  
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Originally Posted by jscott82
wow... what type of ayncronizer is it using? Even dog-ring would need lift wouldn't it?
I'm sorry, I had assumed initially it was PDK but then realized it was a six-speed.

As pointed out, the latest versions of the GT3 manual (after the reintroduction, I guess) have some very sophisticated electronics to make this possible both in part and under full throttle.
Old 01-08-2024, 01:08 PM
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I'm sorry, I would never do this w/o using the clutch on a street car, regardless of the electronic. Upshift w/o lifting off the gas? Yes. Not use the clutch? No.
Old 01-08-2024, 01:09 PM
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Here's the best video I've seen about it.

Old 01-08-2024, 02:33 PM
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Originally Posted by Veloce Raptor
I'm sorry, I would never do this w/o using the clutch on a street car, regardless of the electronic. Upshift w/o lifting off the gas? Yes. Not use the clutch? No.
Have to use the clutch, just don't have to lift off. Start at 8:00 for the explanation. Start the video around 8:54 for the demo.


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