991 gt3 RS Transmission Choices - Further Speculation!
08-27-2012, 08:32 PM
#121
Three Wheelin'
I still believe that manufacturers goal is to force everyone into the lowest common denominator.
08-27-2012, 08:45 PM
#122
Race Director
http://www.porsche.com/microsite/tec...lectedVariant=
http://www.porsche.com/microsite/tec...lectedVariant=
Brakes, not a mechanical LSD. There's a significant difference there.
http://www.porsche.com/microsite/tec...lectedVariant=
Brakes, not a mechanical LSD. There's a significant difference there.
08-27-2012, 09:04 PM
#123
Nordschleife Master
I do understand the difference and realize that PTV uses braking on the inside rear wheel to help rotate the car in a turn. I have PTV on my Cayenne S. But the PTV feature on the 991 comes along with a mechanical LSD (22% in traction 27% in overrun; the same as on my 997.2 S), at least according to the Porsche web site. The passage that I highlighted with bolding and that you copied in your reply to me, is taken directly from the Porsche site which describes the various standard and optional features that are available on the car. Even the second microsite link that you pointed to mentions the included mechanical limited slip differential in the first paragraph.
http://www.6speedonline.com/forums/b...dissected.html
I only say that since it's the same locking factor as the Cayman and Porsche has been known to standardize in recent years. Even if it's the same as a GT3, it's useless...
https://rennlist.com/forums/997-gt2-...sd-buster.html
08-27-2012, 09:12 PM
#124
Race Director
Maybe I am mistaken. It would not be the first time. But even if they offer an LSD, it likely looks like this:
http://www.6speedonline.com/forums/b...dissected.html
I only say that since it's the same locking factor as the Cayman and Porsche has been known to standardize in recent years. Even if it's the same as a GT3, it's useless...
https://rennlist.com/forums/997-gt2-...sd-buster.html
http://www.6speedonline.com/forums/b...dissected.html
I only say that since it's the same locking factor as the Cayman and Porsche has been known to standardize in recent years. Even if it's the same as a GT3, it's useless...
https://rennlist.com/forums/997-gt2-...sd-buster.html
Thanks for the links, BTW.
08-27-2012, 10:29 PM
#125
Nordschleife Master
08-27-2012, 10:54 PM
#126
Race Director
I'll openly admit that I don't follow closely every new street car variation that Porsche offers. I was just told by a certain race team that they were unable to buy a 991 with an LSD. I took them at face value. And then at their prompting, we designed an LSD. Watch the magazines (and potentially here since this particular team is a RL sponsor) for a new product announcement about a 991/PDK LSD...
I'm sure your new piece will be far superior to the OEM offering. 
08-27-2012, 11:57 PM
#127
Nordschleife Master
You know how racers are, they want the least electronically encumbered vehicle to start with. The more electronics they have to overcome the more problems there are with building a car. As it is, they've had their 997 chassis cars back to the dealers mutiple times to clear random codes that the "systems" throw at you. More to follow.
Hint: Watch the race at Laguna Seca in 2 weeks...
Hint: Watch the race at Laguna Seca in 2 weeks...
08-28-2012, 12:10 AM
#128
Race Director
GT gears, 991 PDK LSD....same as 997 PDK LSD? Hummmm ;-)
08-30-2012, 05:27 PM
#129
Latest Porsche 911 Performs the Perfect Shift... Without You
Latest Porsche 911 Performs the Perfect Shift... Without You
"Any gearhead worth their weight in engine oil has painstakingly developed the art of heel-and-toeing; simultaneously matching the engine speed with the transmission’s input shaft to elicit a perfectly smooth downshift. But the latest advancement from Porsche will make all that late-night throttle/brake ballet practice for naught.
If you’re unfamiliar with the concept of the heel-and-toe downshift, its name can be a bit misleading. In cars equipped with a manual transmission, drivers obsessed with keeping the vehicle weight from transitioning abruptly during a downshift (going from fifth to fourth, fourth to third, etc. can unsettle the vehicle at speed) will push in the clutch, shift into the lower gear, and while applying pressure to the brake to slow the car with their right foot, they pivot their heel to stab the throttle. This matches the engine revs with the transmission speed, and when they then let out the clutch, it’s a seamless transfer of power. And all of this happens in less than a second.
The computer in Porsche’s latest all-wheel-drive 911 models – the Carrera 4 and Carrera 4S equipped with the Sport Chrono package – is smart enough to recognize when the driver wants to downshift in the manual transmission models, and automatically matches the engine speed, negating the need for fancy footwork.
But to give credit where credit’s due, this latest advancement isn’t that new. Nissan began fitting a similar technology – dubbed SynchroRev Match – to the 370Z when it was introduced in 2008. It does the same thing as this new Porsche system, but features an on/off switch to allow shifting purists to eliminate the unwanted technological advance.
According to a Porsche spokesman, the system is only active when the driver selects the “Sport Plus” driving mode, so in Normal and Sport mode, the system is deactivated. But the fact that drivers can’t disable the system no matter what mode they’ve chosen will surely be a sticking point with a fraction of enthusiasts. But they’d better get used to it. The new rev-matching feature will eventually roll out to the rest of the 911 range in the coming years, and there’s little doubt it will find its way into other Porsche models equipped with a stick shift, including two of our perennial favorites: the Boxster and Cayman."
Latest Porsche 911 Performs the Perfect Shift -- Wired article link
If you’re unfamiliar with the concept of the heel-and-toe downshift, its name can be a bit misleading. In cars equipped with a manual transmission, drivers obsessed with keeping the vehicle weight from transitioning abruptly during a downshift (going from fifth to fourth, fourth to third, etc. can unsettle the vehicle at speed) will push in the clutch, shift into the lower gear, and while applying pressure to the brake to slow the car with their right foot, they pivot their heel to stab the throttle. This matches the engine revs with the transmission speed, and when they then let out the clutch, it’s a seamless transfer of power. And all of this happens in less than a second.
The computer in Porsche’s latest all-wheel-drive 911 models – the Carrera 4 and Carrera 4S equipped with the Sport Chrono package – is smart enough to recognize when the driver wants to downshift in the manual transmission models, and automatically matches the engine speed, negating the need for fancy footwork.
But to give credit where credit’s due, this latest advancement isn’t that new. Nissan began fitting a similar technology – dubbed SynchroRev Match – to the 370Z when it was introduced in 2008. It does the same thing as this new Porsche system, but features an on/off switch to allow shifting purists to eliminate the unwanted technological advance.
According to a Porsche spokesman, the system is only active when the driver selects the “Sport Plus” driving mode, so in Normal and Sport mode, the system is deactivated. But the fact that drivers can’t disable the system no matter what mode they’ve chosen will surely be a sticking point with a fraction of enthusiasts. But they’d better get used to it. The new rev-matching feature will eventually roll out to the rest of the 911 range in the coming years, and there’s little doubt it will find its way into other Porsche models equipped with a stick shift, including two of our perennial favorites: the Boxster and Cayman."
Latest Porsche 911 Performs the Perfect Shift -- Wired article link
:why:
08-30-2012, 06:19 PM
#131
Still plays with cars.
Lifetime Rennlist
Member
I wonder if it also prevents the "money shift"? Besides, I want PDK in my next RS. I have done heel and toe a few hundred thousand times. I can do it, even in a cup car without auto-blip. But, on a track, nothing beats PDK. I guess that makes me an outcast D Sorry to disappoint, John.
08-30-2012, 06:27 PM
#132
Admin
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Well if it allows you to hunt P1 from that damn Viper, by all means, go ahead and get the PDK one. 
From my end of the scope , well let's just say that I am currently looking for that perfect early Sunday empty mountain road. A good old-school manual is mandatory there. (made in Germany or not)
Btw I can't think that the rev match can (or will) prevent a money shift, unless of course they fit a mechanical gate lock on the shifter or something.
From my end of the scope , well let's just say that I am currently looking for that perfect early Sunday empty mountain road. A good old-school manual is mandatory there. (made in Germany or not)
Btw I can't think that the rev match can (or will) prevent a money shift, unless of course they fit a mechanical gate lock on the shifter or something.
08-30-2012, 06:53 PM
#134
Three Wheelin'
PDK - will make me look like I can shift perfectly -
Manual - yes.. fun... purist will enjoy it.. involves the driver input and rewards them if they do it right but can be punishing if you mis-shift (5th to 2nd gear noob mistake
then kaboom..)
I bet I will probably love PDK on GT3 - but currently I love 6 speed manual for sure
Manual - yes.. fun... purist will enjoy it.. involves the driver input and rewards them if they do it right but can be punishing if you mis-shift (5th to 2nd gear noob mistake
then kaboom..)I bet I will probably love PDK on GT3 - but currently I love 6 speed manual for sure
08-30-2012, 07:37 PM
#135
Drifting
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that description of double declutching by Wired magazine is wrong.
The procedure is
engage clutch
shift into neutral
disengage clutch
use throttle to match engine revs required to drive at current speed in the gear about to be selected
engage clutch
select gear
disengage clutch
do this properly and the clutch is superfluous
when you have this sorted you can try doing this whilst braking, called a heel-and-toe it might more properly be called a big-toe-and-side-of-foot.
R+C
The procedure is
engage clutch
shift into neutral
disengage clutch
use throttle to match engine revs required to drive at current speed in the gear about to be selected
engage clutch
select gear
disengage clutch
do this properly and the clutch is superfluous
when you have this sorted you can try doing this whilst braking, called a heel-and-toe it might more properly be called a big-toe-and-side-of-foot.
R+C