Mike in CA

+1. Guess I don't see the point either......

Z356

The 7MT has been out now for months on the 991! Many ordered it with 'Sport Chrono'. Are you saying that starting soon, the 7MT will be built differently than the earlier 7MT that just came out on the 991? That is strange! PAG delayed introduction of the manual 991 by almost 6 months to finish their 'development'. And now it's being totally revamped with double wet clutches on the 7MT? But only when ordered with the Sport Chrono so-called 'pack'? Please explain it a bit further since to you this is basic given your business but to many of us we are still trying to understand what 'automatic' double-declutches means on a manual!

Saludos,
Eduardo

Mike in CA

I don't think that's it. Someone posted cutaway drawings a while back (wish I could find them) comparing PDK and the new 7 sp MT. I'm certain the MT had a single input shaft, not the dual shafts that would be required with dual clutches and gear pre-selection. I can't imagine Porsche offering a third redesigned transmission choice just to work with sport chrono.

FWIW, Nissan has offered rev matching throttle blips with the MT in the 350/370 ZX for some time. Maybe this is something similar, although the de-clutching part if it's being described accurately, is puzzling.

blake

This thread has been thoroughly enjoyable... Half of the posters will be eating crow, and then we will experience "Act 2" of either denial or admission....

Pass the popcorn please.

Z356

Porsche today just announced the following in conjunction with the release of the new 991 C4S and C4:

"Driving 911 cars with a manual gearbox and Sport Chrono pack can now be even sportier: In Sport Plus mode, the system automatically double-declutches during downshifts."

Can anyone here explain how that works? Should we assume it will be available on regular C2 and C2S manual transmissions too if ordered with the 'new' Sport Chrono' pack! What does the new 'sport chrono' pack cost vs the old 991 'sport chrono'...or is it just added at no extra cost? Does this new double-declutching technology make the manual transmission more attractive now? It would seem so to me!

I started the discussion earlier this morning over at the thread speculating on possible 'sequential' transmission on the next 991 gt3 RS, but it deserves to be discussed by the wider public on this forum. Here are our discussions we had so far this morning among GT gears, myself and Mike in CA. Please add your thoughts to this discussion!

Quote:Originally Posted by GTgears
"That's marketing speak for the PDK functionality of preselecting a gear prior to actually shifting will still be present in the 7MT gearbox. What it sounds to me is that the sport chrono version of the 7MT is going to have double wet clutches like a PDK versus a single dry clutch as used in a traditional manual gearbox."

Quote:Originally Posted by z356
"The 7MT has been out now for months on the 991! Many ordered it with 'Sport Chrono'. Are you saying that starting soon, the 7MT will be built differently than the earlier 7MT that just came out on the 991? That is strange! PAG delayed introduction of the manual 991 by almost 6 months to finish their 'development'. And now it's being totally revamped with double wet clutches on the 7MT? But only when ordered with the Sport Chrono so-called 'pack'? Please explain it a bit further since to you this is basic given your business but to many of us we are still trying to understand what 'automatic' double-declutches means on a manual!"

Quote:Originally Posted by Mike in CA
"I don't think that's it. Someone posted cutaway drawings a while back (wish I could find them) comparing PDK and the new 7 sp MT. I'm certain the MT had a single input shaft, not the dual shafts that would be required with dual clutches and gear pre-selection. I can't imagine Porsche offering a third redesigned transmission choice just to work with sport chrono. FWIW, Nissan has offered rev matching throttle blips with the MT in the 350/370 ZX for some time. Maybe this is something similar, although the de-clutching part if it's being described accurately, is puzzling."

Saludos,
Eduardo
Carmel

GTgears

It's all part of Porsche's long established game.

The just released 991 cannot be purchased this year in any trim level with an LSD. Porsche has done this several times when releasing new models of the car. Then a year or two later they make a special edition or activate the M220 option for one to tick when ordering the car. It gets you to come back and buy the latest and greatest with all the improvements 2 or 3 years later.

It's the oldest trick in the automotive marketing book. How many times has Porsche released a new model and not sold the S variant the first year? They never give you all the bells and whistles the first year of production. The only time I have ever seen Porsche do this was with the Cayman in 2005, when they started the line with the S. Otherwise the traditional pattern is to keep making the cars better and more equipped throughout the lifespan of the production cycle with the bestest of the breed being their swan song before they go out of production with a model.

Mike in CA

Only if you mean as a stand-alone. It's available on the base and standard on the S with PTV......

PTV in conjunction with the manual gearbox, or PTV Plus with Porsche Doppelkupplung (PDK), are available as options for the 911 Carrera models and standard in the 911 Carrera S models. Both systems actively enhance vehicle dynamics and stability. Operating in conjunction with a mechanical (PTV) or electronic (PTV Plus) rear differential lock, they work by braking the rear wheels as the situation demands.


Porsche Torque Vectoring (PTV)

Variable torque distribution through conrolled braking on the rear wheels. Includes mechanically controlled differential lock with asymmetrical locking action (22% in traction, 27% in overrun) for increased agility, steering precision, traction, and vehicle stability

Z356

GT Gears: The issue is not how impervious I am to Porsche's marketing given my 40 years of Porsche ownership - I will let my friend Pete (Savyboy) give me lectures about all of that in good humor! The fact is that many of us are not technically savvy and come to these forums to ask TECHNICAL explanations for these new developments. It has been a few hours since I posed the question and I am still confused as to how this technology actually works on a 7MT transmission.

Back on topic, the Porsche announcement this morning included this "In Sport Plus mode, the system automatically double-declutches during downshifts."

You stated previously that you think that the 'sport chrono version of the 7MT is going to have double wet clutches like a PDK'. Chris in Ca thinks differently and I asked you if you actually thought that PAG would make two versions of 7MT, one for those with 'Sport Chrono' and the other for those who don't order that option. Because it's clear that it will only do the 'auto double-clutching' on Sport Plus, which is a 'Sport Chrono' dependent feature! It seems to me that it's a software enhancement to 'Sport Chrono' in conjunction with 7MT, but that is only a guess.

Can you shed more technical light on this subject?

Saludos,
Eduardo

savyboy

Tasty, very tasty.



I welcome and enjoy candid shots as much as the next guy.

What tweaks me is when forum or poster or website X posts "SUPER SECRET SPY PHOTOS THAT ONLY WE FOUND" when it was fed to them by Porsche.

Porsche doesn't play that sh*t with 918 buyers, all manner of mules are (transparently) made available to the press and public along with PM's and engineers and even invites prospects to various showings. It seems the are willing to show respect to folks willing to part with $700k+.

This whole GT3 song and dance, dribbling of "spy" information out for the sake of creating buzz is to me, their target buyer, insulting. And it has been for a long time.

To each his own.

savyboy

LOL!



I am entitled to a rant every now and then!

Z356

Yes, you have earned it! Even Andreas Preuninger would get a chuckle from your rant and you know he likes you (and your wallet) a lot!

Saludos,
Eduardo

Suns_PSD

I'll take a gander at what double declutch means.

In an 18 wheeler you can shift faster if you "double clutch". Basically you press the pedal in (1st declutch), throw the manual shifter in to neutral, let the clutch out which causes some input and output shafts or something to synchronize speeds by momentarily connecting to each other, press the clutch back in (2nd declutch) and then engage in the new gear. It's needed because on those large transmissions they don't have much in the way of synchronizers given the torque requirements of the transmissions. If you don't double clutch you have to rev match, which is fine but takes longer. When you double clutch it's very quick, like a 1-2 dance step one after the other where you just bounce your leg real quickly.

Just guessing here but I'm thinking the clutch momentarily reengages (connects) even while you have the clutch pedal depressed so as to make shifts, particularly downshifts much smoother. And I can only imagine that it happens so quickly that it is seamless to the driver on a 991 GT3.

The slickest system I have driven is the 370Z w/ synchromatch. It's really nice because which ever gear you aim for the revs jump up (or down) to match. Cool! Even your granny can perfectly rev match and heel toe now in a 370Z.

DJN

I'll bet Porsche Marketing is missing something in the German to English translation......it probably means an auto-blip during a downshift in Sport Plus mode. There is really no need to do "double-declutches during downshifts" on a modern manual transmission in good condition.

Let's wait a see.
Doug N

gstahl

+1 for it really being an auto-blipper

NJ-GT

This is the gizmo stuff in the Nissan 370Z, auto-blipping on downshift.

This is what happens when Porsche uses a Nissan GTR to benchmark the next GT3, and a Nissan 370Z to benchmark the 991S. What's next? benchmarking the next Panamera using a Nissan Altima, and the Cayenne with the Juke.