Any News on 8 spd Auto?
06-30-2014, 05:25 PM
#1
Intermediate
Thread Starter
Member Since: Jun 2009
Location: Chicago il
Posts: 36
Likes: 0
Received 0 Likes
on
0 Posts
Any News on 8 spd Auto?
I am putting in an order for a 2015 Z51 Coupe and debating between 7 speed manual and 8 speed automatic. I have driven the current 6 speed on the track and wasn't sold on that. Hoping the new 8 speed is tighter converter match and more responsive on shifting- closer to Porsche PDK in Sport Plus mode. Has any news leaked on the new 8 speed? I have a feeling it is going to be good but have heard no reports yet.
06-30-2014, 06:04 PM
#2
Tech Contributor
Member Since: Jan 2006
Location: Saint Louis MO
Posts: 4,761
Likes: 0
Received 218 Likes
on
110 Posts
St. Jude Donor '14-'15
GM Press Release (04/07/2014):
2015 Corvette Stingray to Offer Eight-Speed Automatic.
Paddle-shift gearbox rivals dual-clutch performance, enhances efficiency.
DETROIT – An eight-speed paddle-shift automatic transmission will be offered in the Chevrolet Corvette Stingray for 2015, enhancing the performance and efficiency of the 2014 North American Car of the Year. Designed and built by GM, the new transmission delivers world-class shift times that rival the best dual-clutch designs.
The all-new, GM-designed 8L90 eight-speed is expected to contribute up to 5-percent greater efficiency, when compared to the previous six-speed automatic. EPA fuel economy test results are pending and will be announced later. It also makes the Corvette Stingray one of the few sports cars to offer the choice of a conventional manual transmission or an eight-speed automatic.
"Corvette Stingray's new eight-speed automatic delivers the comfort and drivability of a true automatic transmission, as well as lightning-fast shifts and the manual control that enhance the performance-driving experience," said Bill Goodrich, assistant chief engineer for eight-speed automatic transmissions. "It was designed to enhance the Stingray's driving experience, with performance on par with dual-clutch designs, but without sacrificing refinement."
The available 8L90 transmission is based on the same eight-speed automatic that will be offered on the supercharged 2015 Corvette Z06, but with unique clutch and torque converter specifications matched to the torque capacity of the Stingray's LT1 6.2L naturally aspirated engine.
For performance driving, the transmission offers full manual control via steering wheel paddles. A new transmission-control system and unique algorithms deliver shift performance that rivals the dual-clutch/semi-automatic transmissions found in many supercars – but with the smoothness and refinement that comes with a conventional automatic fitted with a torque converter.
The transmission controller analyzes and executes commands 160 times per second. Wide-open throttle upshifts are executed up to eight-hundredths of a second quicker than those of the dual-clutch transmission offered in the Porsche 911.
Smaller steps between gears, compared to the previous six-speed automatic, keep the engine within the sweet spot of the rpm band, making the most of its horsepower and torque to optimize performance and efficiency.
With four gearsets and five clutches, creative packaging enables the new eight-speed automatic to fit the same space as the previous six-speed automatic. Extensive use of aluminum and magnesium make it more than eight pounds, or 4 kg, lighter than the six-speed. Design features that reduce friction contribute to the expected 5-percent greater efficiency.
The 8L90 is built at GM's Toledo, Ohio, transmission facility.
(8-spd auto as seen in the C7 Z06)
Paddle-shift gearbox rivals dual-clutch performance, enhances efficiency.
DETROIT – An eight-speed paddle-shift automatic transmission will be offered in the Chevrolet Corvette Stingray for 2015, enhancing the performance and efficiency of the 2014 North American Car of the Year. Designed and built by GM, the new transmission delivers world-class shift times that rival the best dual-clutch designs.
The all-new, GM-designed 8L90 eight-speed is expected to contribute up to 5-percent greater efficiency, when compared to the previous six-speed automatic. EPA fuel economy test results are pending and will be announced later. It also makes the Corvette Stingray one of the few sports cars to offer the choice of a conventional manual transmission or an eight-speed automatic.
"Corvette Stingray's new eight-speed automatic delivers the comfort and drivability of a true automatic transmission, as well as lightning-fast shifts and the manual control that enhance the performance-driving experience," said Bill Goodrich, assistant chief engineer for eight-speed automatic transmissions. "It was designed to enhance the Stingray's driving experience, with performance on par with dual-clutch designs, but without sacrificing refinement."
The available 8L90 transmission is based on the same eight-speed automatic that will be offered on the supercharged 2015 Corvette Z06, but with unique clutch and torque converter specifications matched to the torque capacity of the Stingray's LT1 6.2L naturally aspirated engine.
For performance driving, the transmission offers full manual control via steering wheel paddles. A new transmission-control system and unique algorithms deliver shift performance that rivals the dual-clutch/semi-automatic transmissions found in many supercars – but with the smoothness and refinement that comes with a conventional automatic fitted with a torque converter.
The transmission controller analyzes and executes commands 160 times per second. Wide-open throttle upshifts are executed up to eight-hundredths of a second quicker than those of the dual-clutch transmission offered in the Porsche 911.
Smaller steps between gears, compared to the previous six-speed automatic, keep the engine within the sweet spot of the rpm band, making the most of its horsepower and torque to optimize performance and efficiency.
With four gearsets and five clutches, creative packaging enables the new eight-speed automatic to fit the same space as the previous six-speed automatic. Extensive use of aluminum and magnesium make it more than eight pounds, or 4 kg, lighter than the six-speed. Design features that reduce friction contribute to the expected 5-percent greater efficiency.
The 8L90 is built at GM's Toledo, Ohio, transmission facility.
(8-spd auto as seen in the C7 Z06)
06-30-2014, 07:00 PM
#3
Intermediate
Thread Starter
Member Since: Jun 2009
Location: Chicago il
Posts: 36
Likes: 0
Received 0 Likes
on
0 Posts
Theta, thanks for info. I have read a couple of quotes from the press release but hadn't seen the whole thing. I was hoping to find someone who had driven C7 with the 8 speed (although I know that is unlikely).
06-30-2014, 07:37 PM
#4
Tech Contributor
Member Since: Jan 2006
Location: Saint Louis MO
Posts: 4,761
Likes: 0
Received 218 Likes
on
110 Posts
St. Jude Donor '14-'15
I figured that's what you were after, but you won't find it here (or anywhere) yet.
It's still only in GM's test mules, and nobody will risk their job to prove they've driven it. The NDA does not expire for a good while longer. Anyone at this point who posts here claiming to have actually driven one with the A8 is not being factual.
Sorry, just how it is.
I'd imagine this really will be evolutionary vs the outgoing A6, though.
It's still only in GM's test mules, and nobody will risk their job to prove they've driven it. The NDA does not expire for a good while longer. Anyone at this point who posts here claiming to have actually driven one with the A8 is not being factual.
Sorry, just how it is.
I'd imagine this really will be evolutionary vs the outgoing A6, though.
06-30-2014, 08:56 PM
#5
Intermediate
Thread Starter
Member Since: Jun 2009
Location: Chicago il
Posts: 36
Likes: 0
Received 0 Likes
on
0 Posts
Yes, suspect you are right re evolutionary. I haven't bought an auto in Corvettes since 1987 C4 (what a disappointment). Their manuals have been great in late C4, C5 & C6 Z06. Tough decision.
06-30-2014, 09:25 PM
#6
Tech Contributor
Member Since: Jan 2006
Location: Saint Louis MO
Posts: 4,761
Likes: 0
Received 218 Likes
on
110 Posts
St. Jude Donor '14-'15
The M7 is excellent in my opinion, which is an opinion shared by many.
The A6 is surprisingly crisp in the C7, and the A8 is supposedly quite a bit faster. If this is, indeed, true, it's going to be one hell of a transmission.
So, it will come down to taste and preference. Even though A6/A8 will be faster down the track, I'm just a stick guy - more fun to me, but my wife hates that all of my cars can't be driven (by her anyway).
The A6 is surprisingly crisp in the C7, and the A8 is supposedly quite a bit faster. If this is, indeed, true, it's going to be one hell of a transmission.
So, it will come down to taste and preference. Even though A6/A8 will be faster down the track, I'm just a stick guy - more fun to me, but my wife hates that all of my cars can't be driven (by her anyway).
06-30-2014, 09:58 PM
#7
Instructor
I figured that's what you were after, but you won't find it here (or anywhere) yet.
It's still only in GM's test mules, and nobody will risk their job to prove they've driven it. The NDA does not expire for a good while longer. Anyone at this point who posts here claiming to have actually driven one with the A8 is not being factual.
Sorry, just how it is.
I'd imagine this really will be evolutionary vs the outgoing A6, though.
It's still only in GM's test mules, and nobody will risk their job to prove they've driven it. The NDA does not expire for a good while longer. Anyone at this point who posts here claiming to have actually driven one with the A8 is not being factual.
Sorry, just how it is.
I'd imagine this really will be evolutionary vs the outgoing A6, though.
What about the 2014 CTS V-Sport?
I drove one the other day, and it has the 8-speed in it... that thing was wicked fast and smooth to boot. I am a manual only guy but I REALLY liked that trans.
Go drive a CTS V-Sport and check out that transmission!
06-30-2014, 10:02 PM
#9
The V-Sport has an 8 speed Aisin, the 8L90 wasn't ready for the CTS launch. It also is used in the RWD (but not AWD) NA 3.6 CTS, not sure about the 2.0T version. One of the reasons I didn't buy a 2014 CTS was I didn't want an "orphan" transmission since GM will likely start using their own 8L90 instead of the Aisin unit very soon.
We tied there.
06-30-2014, 10:04 PM
#11
Instructor
I figured that's what you were after, but you won't find it here (or anywhere) yet.
It's still only in GM's test mules, and nobody will risk their job to prove they've driven it. The NDA does not expire for a good while longer. Anyone at this point who posts here claiming to have actually driven one with the A8 is not being factual.
Sorry, just how it is.
I'd imagine this really will be evolutionary vs the outgoing A6, though.
It's still only in GM's test mules, and nobody will risk their job to prove they've driven it. The NDA does not expire for a good while longer. Anyone at this point who posts here claiming to have actually driven one with the A8 is not being factual.
Sorry, just how it is.
I'd imagine this really will be evolutionary vs the outgoing A6, though.
Wasn't sure if that was it... but... I was impressed, so if they're anywhere near that with their own unit it'll be a real winner.
06-30-2014, 10:13 PM
#12