991 GT3 PDK features - sailing?
10-31-2014, 03:43 PM
#16
Three Wheelin'
Just some clarification about "kickdown".
Any automatic transmission (slushbox or dual clutch) in automatic mode will downshift on its own if it senses the need for better acceleration (based usually throttle position or how rapid you press the throttle). That's why it's an "automatic". Some automatic transmissions are more sensitive than others in sensing the need for donwshifts. Most performance tuned automatic transmissions will tend to have a lower threshold for downshifting compared to those transmissions tuned for comfort.
For most automatic transmissions, there is a kickdown "button" or "click" when you floor the throttle. By activating the button or "click", the car knows for SURE that you want maximum acceleration and will downshift appropriately to the lowest gear possible given your current rpm to get the maximum acceleration possible.
In the 991 GT3, there is no kickdown "button" or "click" when you floor the throttle. However, when driving in automatic normal or sport modes, it will downshift very easily if you are more aggressive with the throttle.....ie it will still automatically downshift if it senses you want better acceleration based on the throttle inputs.
In manual mode of the 991 GT3, there is absolutely no automatic downshifting no matter how aggressive with the throttle you are. The only time it will downshift on its own is to prevent stalling the car at very low rpms.
Any automatic transmission (slushbox or dual clutch) in automatic mode will downshift on its own if it senses the need for better acceleration (based usually throttle position or how rapid you press the throttle). That's why it's an "automatic". Some automatic transmissions are more sensitive than others in sensing the need for donwshifts. Most performance tuned automatic transmissions will tend to have a lower threshold for downshifting compared to those transmissions tuned for comfort.
For most automatic transmissions, there is a kickdown "button" or "click" when you floor the throttle. By activating the button or "click", the car knows for SURE that you want maximum acceleration and will downshift appropriately to the lowest gear possible given your current rpm to get the maximum acceleration possible.
In the 991 GT3, there is no kickdown "button" or "click" when you floor the throttle. However, when driving in automatic normal or sport modes, it will downshift very easily if you are more aggressive with the throttle.....ie it will still automatically downshift if it senses you want better acceleration based on the throttle inputs.
In manual mode of the 991 GT3, there is absolutely no automatic downshifting no matter how aggressive with the throttle you are. The only time it will downshift on its own is to prevent stalling the car at very low rpms.
https://rennlist.com/forums/991-gt3/...-question.html
PDK-S has the following modes:
Auto (roughly equivalent to regular PDK sport) - has a kickdown function triggered by software when throttle is at 100%
Auto Sport - does not have a kickdown function, when driver applies 100% throttle, the car maintains the same gear
Manual - current owners cannot tell the difference between sport and non-sport when in manual mode.
Ryan
10-31-2014, 04:00 PM
#17
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The PDK-S shifting modes were discussed extensively in this thread:
https://rennlist.com/forums/991-gt3/...-question.html
PDK-S has the following modes:
Auto (roughly equivalent to regular PDK sport) - has a kickdown function triggered by software when throttle is at 100%
Auto Sport - does not have a kickdown function, when driver applies 100% throttle, the car maintains the same gear
Manual - current owners cannot tell the difference between sport and non-sport when in manual mode.
Ryan
https://rennlist.com/forums/991-gt3/...-question.html
PDK-S has the following modes:
Auto (roughly equivalent to regular PDK sport) - has a kickdown function triggered by software when throttle is at 100%
Auto Sport - does not have a kickdown function, when driver applies 100% throttle, the car maintains the same gear
Manual - current owners cannot tell the difference between sport and non-sport when in manual mode.
Ryan
First of all, "kickdown" and automatic downshifting are different things. Please read my post about what "kickdown" classically refers to. The 991 GT3 does not have a kickdown button at the bottom of the throttle pedal.
In automatic normal mode of the 991 GT3, you don't have to have the throttle at 100% for the car to downshift........any rapid throttle input, and the transmission will downshift on its own to help maximize acceleration.......of coures, if you floor it, it will also automatically downshift. Like I said before, ALL automatic transmissions will do this......some are more sensitive than others.
In automatic sport mode of the 991 GT3, it essentially is the same as normal mode, except that the upshift points will be at higher rpm''s and the transmission will keep itself always at higher rpm's so that it's always in the meat of the engine's powerband. It will still upshift and downshift automatically (hence that's why it's still an "automatic").
In manual mode of the 991 GT3, I agree there is likely no difference between pushing the sport button or not.
10-31-2014, 05:26 PM
#18
Three Wheelin'
Sorry, but I think you are incorrect about some things.
First of all, "kickdown" and automatic downshifting are different things. Please read my post about what "kickdown" classically refers to. The 991 GT3 does not have a kickdown button at the bottom of the throttle pedal.
In automatic normal mode of the 991 GT3, you don't have to have the throttle at 100% for the car to downshift........any rapid throttle input, and the transmission will downshift on its own to help maximize acceleration.......of coures, if you floor it, it will also automatically downshift. Like I said before, ALL automatic transmissions will do this......some are more sensitive than others.
In automatic sport mode of the 991 GT3, it essentially is the same as normal mode, except that the upshift points will be at higher rpm''s and the transmission will keep itself always at higher rpm's so that it's always in the meat of the engine's powerband. It will still upshift and downshift automatically (hence that's why it's still an "automatic").
In manual mode of the 991 GT3, I agree there is likely no difference between pushing the sport button or not.
First of all, "kickdown" and automatic downshifting are different things. Please read my post about what "kickdown" classically refers to. The 991 GT3 does not have a kickdown button at the bottom of the throttle pedal.
In automatic normal mode of the 991 GT3, you don't have to have the throttle at 100% for the car to downshift........any rapid throttle input, and the transmission will downshift on its own to help maximize acceleration.......of coures, if you floor it, it will also automatically downshift. Like I said before, ALL automatic transmissions will do this......some are more sensitive than others.
In automatic sport mode of the 991 GT3, it essentially is the same as normal mode, except that the upshift points will be at higher rpm''s and the transmission will keep itself always at higher rpm's so that it's always in the meat of the engine's powerband. It will still upshift and downshift automatically (hence that's why it's still an "automatic").
In manual mode of the 991 GT3, I agree there is likely no difference between pushing the sport button or not.
Ryan
10-31-2014, 06:00 PM
#19
Race Director
Sorry, but I think you are incorrect about some things.
First of all, "kickdown" and automatic downshifting are different things. Please read my post about what "kickdown" classically refers to. The 991 GT3 does not have a kickdown button at the bottom of the throttle pedal.
In automatic normal mode of the 991 GT3, you don't have to have the throttle at 100% for the car to downshift........any rapid throttle input, and the transmission will downshift on its own to help maximize acceleration.......of coures, if you floor it, it will also automatically downshift. Like I said before, ALL automatic transmissions will do this......some are more sensitive than others.
In automatic sport mode of the 991 GT3, it essentially is the same as normal mode, except that the upshift points will be at higher rpm''s and the transmission will keep itself always at higher rpm's so that it's always in the meat of the engine's powerband. It will still upshift and downshift automatically (hence that's why it's still an "automatic").
In manual mode of the 991 GT3, I agree there is likely no difference between pushing the sport button or not.
First of all, "kickdown" and automatic downshifting are different things. Please read my post about what "kickdown" classically refers to. The 991 GT3 does not have a kickdown button at the bottom of the throttle pedal.
In automatic normal mode of the 991 GT3, you don't have to have the throttle at 100% for the car to downshift........any rapid throttle input, and the transmission will downshift on its own to help maximize acceleration.......of coures, if you floor it, it will also automatically downshift. Like I said before, ALL automatic transmissions will do this......some are more sensitive than others.
In automatic sport mode of the 991 GT3, it essentially is the same as normal mode, except that the upshift points will be at higher rpm''s and the transmission will keep itself always at higher rpm's so that it's always in the meat of the engine's powerband. It will still upshift and downshift automatically (hence that's why it's still an "automatic").
In manual mode of the 991 GT3, I agree there is likely no difference between pushing the sport button or not.
Let's say you are in PDK Sport auto mode in 5th gear @ 5000 rpm and you brake for a turn or let off the throttle. As the revs drop the gearbox will automatically DOWNSHIFT to a lower gear to keep you in the power band.
Now let's consider the same scenario as above but instead of braking you stomp on the throttle to accelerate. Under these circumstances a normal automatic gearbox will KICKDOWN to a lower gear to accelerate more quickly. PDK-S, however, WILL NOT automatically kickdown in that situation. Neither will it kickdown in either manual mode. It will only kickdown when in normal auto mode.
To repeat, in auto sport mode PDK-S will downshift to a lower gear as revs drop under deceleration but it will not kickdown under acceleration no matter how hard you press the throttle.
10-31-2014, 06:43 PM
#20
I think we may be getting confused by semantics here.
Let's say you are in PDK Sport auto mode in 5th gear @ 5000 rpm and you brake for a turn or let off the throttle. As the revs drop the gearbox will automatically DOWNSHIFT to a lower gear to keep you in the power band.
Now let's consider the same scenario as above but instead of braking you stomp on the throttle to accelerate. Under these circumstances a normal automatic gearbox will KICKDOWN to a lower gear to accelerate more quickly. PDK-S, however, WILL NOT automatically kickdown in that situation. Neither will it kickdown in either manual mode. It will only kickdown when in normal auto mode.
To repeat, in auto sport mode PDK-S will downshift to a lower gear as revs drop under deceleration but it will not kickdown under acceleration no matter how hard you press the throttle.
Let's say you are in PDK Sport auto mode in 5th gear @ 5000 rpm and you brake for a turn or let off the throttle. As the revs drop the gearbox will automatically DOWNSHIFT to a lower gear to keep you in the power band.
Now let's consider the same scenario as above but instead of braking you stomp on the throttle to accelerate. Under these circumstances a normal automatic gearbox will KICKDOWN to a lower gear to accelerate more quickly. PDK-S, however, WILL NOT automatically kickdown in that situation. Neither will it kickdown in either manual mode. It will only kickdown when in normal auto mode.
To repeat, in auto sport mode PDK-S will downshift to a lower gear as revs drop under deceleration but it will not kickdown under acceleration no matter how hard you press the throttle.
10-31-2014, 07:35 PM
#21
Race Director
You can use PDK-S sport auto on the street, but it's not optimal. It has no kickdown, it keeps revs higher than necessary, and it doesn't adapt to your driving style. PDK-S sport auto is really designed specifically as a track mode and when used that way upshifts come close to or at redline and downshifts under braking are very aggressive. One reason for the lack of kickdown in this mode is so that when you begin to accelerate in a long corner or out of a slow one, for example, an aggressive kickdown-style downshift won't upset the balance of the car when you least expect it.
Last edited by Mike in CA; 10-31-2014 at 09:31 PM. Reason: added word for clarification
10-31-2014, 11:10 PM
#23
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That's why the automatic sport mode is so great on track. However, I remember AP saying somewhere that the same effect can be achieved simply by being very aggressive with the throttle inputs in automatic normal mode. The sport automatic mode simply compensates for not so aggressive throttle inputs to keep the revs relatively high.
11-01-2014, 01:17 AM
#24
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Pull the shift lever to the left .use flappy paddles to click a gear or two down then fly by like a screaming banshee. It's not like you weren't prepared to pass or accelerate. I just learned something. This car is an automatic???? Mine always sits in the lever LEFT position. And while I'm in rant mode do you just not love the sequential stick. And in the right way. I do a full 50% of changes with the stick. Still mired in the 5 to 7.5 range but getting there
11-04-2014, 02:40 AM
#26
Instructor
Thread Starter
I'm probably a better C7 Z06 candidate in the spring.
11-04-2014, 10:29 AM
#27
Burning Brakes
PDK has made it more of a daily driver. Even in normal(sport PDK) mode the car will loaf along at 40 mph in 5 gear! In manual mode I don't' think I've ever put PDK in any gear high than fourth except cruising on the interstate at 75. Even then I hate putting it in 6th gear just in case you want to punch it. Driving with PDK in normal automatic is highly annoying. I can count on one hand the number of times I have done this.