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!

Saludos,
Eduardo
Carmel

chuckbdc

I think it means it blips the throttle to match the revs. It you have PSE even more fun.

Z356

Chuck, I don't think it's that simple. I have a 6 sp manual, Sport Chrono, Sport Exhaust and Sport Shifter on my '12 Spyder. It's sure fun...and I have all sorts of blips & sounds as I downshift. But I think this is something new. It says: "In Sport Plus mode, the system automatically double-declutches during downshifts." So it is obviously not related to just every 7MT on the 991, just the ones that opt for the 'Sport Chrono'! So it is software dependent and not just mechanical! But I am not clever enough to understand how this technology works and would like a more sensible explanation from some tech savvy folks in this forum.

Over at the gt3 Rennlist forums, we had this discussion on this subject this morning among GT gears, myself and Mike in CA:

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

ScorpionT

To me, it sounds like they are "dumbing-down" the transmission even further. Not appealing at all.

kosmo

perhaps "double-declutches" is Germanic for "Heel n Toe"?

scott parker

Blips the down change. Probably works like the Nissan 370z system

chuckbdc

Smartening up the transmission: Dumbing down the driver!

Holli82

mmm...

maybe this is the way slowly to transition to an all PDK fleet.

Mike in CA

This was resolved in the similar thread on the GT3 forum. There was a translation error. The feature doesn't "double de-clutch", it just blips the throttle on downshifts.

rijowysock

the new M/t sounded amazing on paper... I even spec'd a build to get one... decided to go to dealer prior and drive the car and me coming from a life long addiction to 6 speeds did not like it at all.. mostly the clutch felt "fake" to me (same feeling as the Evo X, not sure what it is.. but maybe the self adjusting clutch) i just felt very detached from the vehicle versus the normal feeling as if i was part of the car and choosing my gears mechanically.. the trans felt as if I was driving a PDK with longer shift times and a more complicated "gear selector".

i would prefer the manual to be very "frill-less" and direct... if they are going to make it feel identical to the pdk.. why even produce a manual trans?

i guess this feeling comes from the transmissions being the same overall, with parts fabricated to make it manual..

they lost me as a repeat customer... had my mexico blue w/ black interior base MT all spec'd out..

WCE

Some quick internet research reveals "double de-clutching" or double clutching is something only done by truck drivers with non-syncromesh transmissions, so I think it's just Porsche's fancy term for rev matching. Makes the sport chrono pkg more of a "must have" now with the manual then the PDK!

rijowysock

def just rev matching, like the new pdk.. heavy blips on downshifts..

the old manual would almost do it by itself on sport plus mode because of the pedal being "heavier" on the gas... you would almost ride the gas a second longer than you wanted, hence blipping the rev's up.. (at least my experience on 997 when being used to regular mode and going sport plus.

frayed

Not a big fan of PDK but I find this interesting. You still have control over your shift points but the biggest performance gain of the PDK is now in the manual. Can't wait to drive one.

Mike in CA

Sorry, I don't mean to misinterpret your comment: are you saying the biggest performance feature of PDK (that is now in the MT) is rev matching? If so, IMO, the biggest performance gains of PDK are in the speed of the shifts and the fact that you don't have to lift the throttle when you shift. Neither of these advantages will be equaled by the MT now being able to blip the throttle on downshifts. And of course, if you want, you have control of your shift points with PDK too.....

uhn2000

Having recently driven the 7MT and hard - I will go on record as saying its much better then my 997.2 Targa. Its fast and has great feeling - also love the shifter position. Not sure I would like the rev matching but ... would be interesting to see how it works.