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Fuel Low
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Discussion Starter #1
I've read really good reviews about GM's new in-house 8 speed auto. It shifts faster than Porsche's PDK, and it is strong enough to handle the insane beast of a car that is the new Z06, plus it's lighter than the 6l80e. Durability + Speed + improved fuel economy = win :)

I really have no clue what can be made to work with our cars' brains but hopefully this will open up some new possibilities. I'm also interested to see if it'll be cheaper than going the manual conversion route.
 

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The VF Commodore/SS got a brand new electrical architecture over the VE/G8. Gonna be interesting to adapt the two systems, if at all possible/feasible.
 

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every village has one
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Where are you, Chuck??
 

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I've heard they're the same size which make sense because the 2014 to 2015 Vette just swapped the two trannys. Made a nerd chart with gear ratios etc below. Not necessarily a big gain in highway efficiency. I used a 3.27 diff since the A6 GXPs have it (my car) and some of you GT guys switch to the 3.45 camaro so the 2.92s would read a little higher. The A6 would run 73 mph at 2000rpm. The A8 is at 75.

What's really impressive is the 2nd to 5th gear spread for 1/4 mile runs. Most of us barely hit 4th with the A6. We'd stay in the power band much more with that A8. The big power guys would actually make it to 6th crossing the line with the 8L90 if the shifts are as lightning fast as GM claims.
 

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If this swap is possible, I would absolutely put one of these in if it plays nice with our cars electronics.
 

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Don't jump in to fast, a friend is a plant manager retro-fitting a plant in Guelph, Ontario to start production of 9 and 10 speed auto's for GM. Not sure of the time frame I think he said really late 15 or early 16 (can't remember what he told me) but they will be in all GM full size cars..
 

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Fuel Low
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Discussion Starter #8
What's really impressive is the 2nd to 5th gear spread for 1/4 mile runs. Most of us barely hit 4th with the A6. We'd stay in the power band much more with that A8.
This is good stuff. Also, I read that GM specifically made this transmission track ready and highly resistant to overheating. To me, this is one of the best areas they could have focused on. My transmission had no issues managing heat at the strip but 1 event at a road course and it was never the same again.
 

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Not sure of the time frame I think he said really late 15 or early 16 (can't remember what he told me) but they will be in all GM full size cars..
Absolutely not true....

dont ask me how I know... :)
 

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I would for sure wait on a swap to the 8L90..... let thinks work itself out before you consider.... i would wait at least another yr....
 

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shame it will never work , unless you swap in the whole transaxle from the vette

since their trans is mounted in the rear and not to the motor likes ours is
 

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The transmission is also in the Escalade and the Silverado/Sierra twins, but is their gearing way different?
 

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I asked about this a while ago. Would be nice if it could happen, and yes, the trans from the truck would likely physically fit. The electronics are the big issue. A custom TCM and likely BCM, and possibly ECM would need to be made to work with our cars.

Never say never, but I doubt the aftermarket will be doing this any time soon.
 

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Discussion Starter #15
shame it will never work , unless you swap in the whole transaxle from the vette

since their trans is mounted in the rear and not to the motor likes ours is
Ya, like Rotz said there are other applications that use the 8 speed without the transaxle configuration. The gearing for the trucks might be conservative, but I really doubt the new ATS-V will be.
 

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Chevrolet Performance Par
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I asked about this a while ago. Would be nice if it could happen, and yes, the trans from the truck would likely physically fit. The electronics are the big issue. A custom TCM and likely BCM, and possibly ECM would need to be made to work with our cars.

Never say never, but I doubt the aftermarket will be doing this any time soon.
Correct.
The 8L90 uses a new TCM that is no longer part of the transmission, which might be a good thing for aftermarket transmission controllers.

The TCM will use the Global-A CAN programming which is different from the older G8 CAN system if I understand it correctly so it may not speak the same CAN language along with all the other electronic parts.
 
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I can't help but wonder what paddle shifting an 8 speed auto would be like...
 

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Discussion Starter #20
^ Yup.

8L90 is Global A; not gonna happen (at least not with 100% factory parts).
What would it take to make this happen?
 
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