PDA

View Full Version : "Staged Upshifts" in older T43's akin to the ZL1 and 2014 Chevy SS



T2000
February 23rd, 2014, 01:40 PM
Hi guys,

Even after all the tinkering I am still searching for some extra performance from my 6L80.
A log of a typical 400m run shows that it is between gears in upshifts for over a second :frown:

I've added paddle shifters but that just seems to highlight the delayed and somewhat clumsy upshifts (when compared to other modern Autos).

There seems to be a little buzz on the interwebs regarding a new OS and calibration in the 6Lxx equipped Camaro ZL1 and the new Chevy SS.
Here is a link to a GM video that outlines that the new OS/Cal includes a logic feature where the oncoming clutch is pre-staged which then reduces the subsequent shift time by 60%. ** Impressive ** :w00t:

http://link.brightcove.com/services/player/bcpid1280283126001?bckey=AQ%7E%7E%2CAAAA9K3O_eE%7E %2CBF-rjVZt6dyR5DIA5zxHwxbIuWQAPTjb&bctid=1465521469001

So...

How would someone achieve this in an older TCM/PCM combo?

Is this feature likely to trickle back to older OS's due to the programming excellence of EFI-Live tech?
or
Is this something that could be added as a CAX by someone that could pick through the newer OS.
or
Will this require a complete upgrade to newer versions of the PCM/TCM/BCM ?


Cheers, Chris

joecar
February 23rd, 2014, 03:02 PM
Hmmm.... interesting, I wonder how they pre-stage the next clutch...

do they partially fill its hydraulic circuit with low pressure fluid (sufficiently low pressure so clutch does not apply)...?

T2000
February 23rd, 2014, 06:18 PM
Hmmm.... interesting, I wonder how they pre-stage the next clutch...

do they partially fill its hydraulic circuit with low pressure fluid (sufficiently low pressure so clutch does not apply)...?

Correct. From the little that I have been able to find out about this... that is exactly what is done, so once the Upshift is commanded/selected it just has to add pressure but does not need to fill the whole circuit.

T2000
February 23rd, 2014, 06:40 PM
A little more info from here: http://media.gm.com/media/us/en/gm/news.detail.html/content/Pages/news/us/en/2012/Feb/0222_tapshift.html


DETROIT – When the new 2012 Chevrolet Camaro ZL1 arrives this spring, performance car enthusiasts will experience the hands-on driving satisfaction of a “stick” with the ease of an automatic transmission due to General Motors’ newly improved TapShift technology.

Since its introduction several years ago, TapShift has allowed drivers to control up- and down-shifts with paddle shifters. For 2012, GM powertrain engineers implemented a patent-pending software algorithm that improves tap response time by up to 60 percent compared to the previous system. No hardware changes were required for the upgrade.

“The faster you can get to the next gear, the better, and from the sound of it, the ZL1 automatic’s performance is going to make paddle shifting more exhilarating and satisfying for drivers of all skill sets,” said Eric Fedewa , director of Global Powertrain Forecasting at IHS Automotive. “We’re seeing a trend toward more manual-mode-capable, fun-to-drive automatic transmissions across all vehicle segments, and GM’s technology is leading the pack.”

The 2012 ZL1’s six-speed automatic transmission delivers a 0-60 time of 3.9 seconds – a tenth of a second faster than the manual transmission time.

By staging hydraulic pressure in the clutch for the next gear, the new control module algorithm reduces tap delay for the 1-2, 2-3, 3-4, and 4-5 up-shifts by 200-300 milliseconds. The system anticipates shift requests based on current gear, throttle, torque and speed. By pre-filling the clutch for the next gear, the tap up-shift response is near instantaneous.

“As great as the previous system’s performance was, we were driven to achieve even better results,” said Gabe Gibson, GM performance car calibration engineer. “Not only did we make the upgrade to Camaro, we implemented it on the 2012 Corvette as well, and will use it on all vehicles with TapShift control going forward.”

Staged up-shifts will help drivers of the 2012 ZL1 – the most powerful production Camaro ever – get the most out of its supercharged 6.2L engine that is SAE-rated at 580 horsepower (432 kW) and 556 lb.-ft. of torque (754 Nm).

ZL1 customers’ choice of an automatic 6L90 transmission with TapShift manual mode or a six-speed manual transmission is unmatched in its class. With 0 to 60 taking 3.9 seconds, and a top speed of 184 mph, the power and acceleration of the ZL1 automatic rivals many supercars.

“We think Camaro drivers will really appreciate the performance improvement offered by staged up-shifts, whether they’re merging onto the freeway or putting their ZL1 through its paces at the track,” Gibson said.

ringram
August 17th, 2014, 08:00 AM
This must be a hardware change as well then?

I wonder if its on all new 6l80e as Ill have a 2014 trans arriving inside a vehicle in a month or so..
Any news on what OS support this feature?

ringram
February 8th, 2015, 10:37 PM
Apparently you need the right controller, otherwise trans the same. I have the staged shifts in the 2014 Maloo R8, works ok. But blipped downshifts are best :)