[hellrotm]

First reviews coming in for new GM 8-speed auto for Stingray and Z06.


Shift time (upshift and downshift)





http://gmauthority.com/blog/2014/08/...e-first-drive/

http://www.autoblog.com/2014/08/20/2...ew-quick-spin/

http://www.motortrend.com/roadtests/...c_first_drive/

[-Wingman-]

I have my doubts. If you skim through the motortrend article, the comparison between the pdk and GM's new 8 speed auto in terms of shift speed is quoted from Kaveh. It wasn't a result of their own test. In fact, they even say that although GM claims the 8 speed auto is very close in terms of performance to the PDK, it doesn't feel as quick. Maybe it's in their head because I sure as hell don't know how a person can tell the difference between .49 seconds and .52 or how .49 seconds could feel slower than .52 seconds to begin with. I don't see these transmissions beating something like a pdk. Maybe a ZF

[hellrotm]

Originally Posted by -Wingman-

I have my doubts. If you skim through the motortrend article, the comparison between the pdk and GM's new 8 speed auto in terms of shift speed is quoted from Kaveh. It wasn't a result of their own test. In fact, they even say that although GM claims the 8 speed auto is very close in terms of performance to the PDK, it doesn't feel as quick. Maybe it's in their head because I sure as hell don't know how a person can tell the difference between .49 seconds and .52 or how .49 seconds could feel slower than .52 seconds to begin with. I don't see these transmissions beating something like a pdk. Maybe a ZF

Yeah I read that in the Motor Trend review, but in the other two reviews they said they felt just as fast as the pdk. Like you said how could you even feel a slight difference like that.

Down to it then. Executing shifts in manual mode feels dual-clutch quick, for sure. The Chevy guys were puffing out their chests talking about the speed of this 8AT versus Porsche's PDK, and the truth is that the reaction time from paddle-pull to upshift is right there. At least, as that's what my imperfect human brain can suss out – any advantage to the quickest dual clutches I've yanked would require a machine to judge.

[-Wingman-]

If it is, that's impressive. I really think since there are conflicting opinions (motor trend vs other articles), someone such as motortrend should conduct a scientific test to see how close the GM tranny is to the PDK. Because let's not forget, not only are they claiming to have developed a fast shifting transmission, they're claiming to beat one of the best dual-clutch transmissions in the industry. Look at their numbers

[See5]

Originally Posted by -Wingman-

If it is, that's impressive. I really think since there are conflicting opinions (motor trend vs other articles), someone such as motortrend should conduct a scientific test to see how close the GM tranny is to the PDK. Because let's not forget, not only are they claiming to have developed a fast shifting transmission, they're claiming to beat one of the best dual-clutch transmissions in the industry. Look at their numbers

I don't doubt their numbers looking at this video. That is one quick transmission. Probably won't "hit" like the dual clutch cars but it shifts FAST. Skip to 3:00.

[-Wingman-]

It's quick, but not as quick as they claim based on the video. Honestly, it shifts only a tad faster than the ZF 8 speed in BMW's. GM is claiming that this transmission shifts faster than the PDK. Look at any video demonstrating the shift speed of a PDK whether it's from some car review from Chris harris or a video showing the rpm gauge and speedometer. The PDK shifts quicker and it's definitely more crisp. Have a look on YouTube.

[hellrotm]

Not sure what PDK they used for comparison. I know the latest PDK in the GT3 is tuned for quicker and more aggressive shifts than lets say the PDK in a Cayman S. As far as the crisp or aggression of the shifts, a standard auto is always going to seem smoother or less race like.

[Ezio]

My biggest problem is that it's a torque converted auto.

[swanson]

Originally Posted by Ezio

My biggest problem is that it's a torque converted auto.

Why? It will perform just as good as a DCT and it will be much better around town.

[DieGrüneHölle]

Originally Posted by Ezio

My biggest problem is that it's a torque converted auto.

Care to elaborate why? If it shifts at or better than dual clutch speeds, holds gears, and allows aggressive downshifts going into corners. Then what is the problem? Just from skimming over the reviews it seems to be very good.

[Amirsm3]

Originally Posted by swanson

Why? It will perform just as good as a DCT and it will be much better around town.

+1 it'll also be cheaper to work on compared to a dual clutch system.

[Ezio]

Originally Posted by Blipit_

Care to elaborate why? If it shifts at or better than dual clutch speeds, holds gears, and allows aggressive downshifts going into corners. Then what is the problem? Just from skimming over the reviews it seems to be very good.

because i like the feel of not having a torque converter. it makes the car feel more like a stick.

[Red Bread]

Originally Posted by Ezio

because i like the feel of not having a torque converter. it makes the car feel more like a stick.

Get it with a stick, you know, like a man.

[swanson]

Its a mental thing. People think having a DCT will make them feel more racy, more Ferrari like. The downfall to all DCT's is the jerky behavior during normal driving and its inability to take too much torque. The real impressive thing to me is the fact the more and more automatic transmissions are coming out with DCT like speed shifting but much, much better everyday, normal driving behavior and can handle a lot more power.

[Amirsm3]

Originally Posted by Ezio

because i like the feel of not having a torque converter. it makes the car feel more like a stick.

Not sure if serious....

You're definitely entitled to your opinion, though.

[Ezio]

Originally Posted by Amirsm3

Not sure if serious....

You're definitely entitled to your opinion, though.

GM is making this transmission in way that its very smooth, but shifts very fast.

my point is i like that more "racey" feel of transmission like the M DCT and SMG.

the new GM tanny may shift fast, but its going to be more numb to me. but i would get a manual corvette anyway.

[Amirsm3]

Originally Posted by Ezio

GM is making this transmission in way that its very smooth, but shifts very fast.

my point is i like that more "racey" feel of transmission like the M DCT and SMG.

the new GM tanny may shift fast, but its going to be more numb to me. but i would get a manual corvette anyway.

Indeed. I do think it's cool, though, that they're offering an automatic Z06. They're gonna sell so many more Z06's than during the C6 Z06 model run

[Ezio]

Originally Posted by Amirsm3

Indeed. I do think it's cool, though, that they're offering an automatic Z06. They're gonna sell so many more Z06's than during the C6 Z06 model run

i liked the fact the Z06 was only in a 6 speed. made them more rare, and more cool IMO (not kidding though)

[Mike_L]

Originally Posted by Ezio

i liked the fact the Z06 was only in a 6 speed. made them more rare, and more cool IMO (not kidding though)

Made them inferior. Manual transmissions are antiquated. They belong in the annuls of history along with drum brakes, live axles, manual windows, etc. There is no reason for them to exist in the 21st century. Time goes on, new, better stuff kicks the old crap to the curb. DCT and automatics are the present and the future. You couldn't pay me to buy a car with a stickshift.

[Red Bread]

Originally Posted by Mike_L

Made them inferior. Manual transmissions are antiquated. They belong in the annuls of history along with drum brakes, live axles, manual windows, etc. There is no reason for them to exist in the 21st century. Time goes on, new, better stuff kicks the old crap to the curb. DCT and automatics are the present and the future. You couldn't pay me to buy a car with a stickshift.

That's cool, you couldn't pay me to buy an automatic. There's little doubt that drive by wire steering, EPS and Google Cars are more advanced and higher tech than something like a BRZ, but I'll always prefer the involving car to the one that has no feel, no matter how big the numbers it puts up are. I like to drive my cars, not just be driven around in them.

[Twix]

I hate how sloppy automatics are from a stop. Clutches have firmer engagement, gets the car going faster.

I think any true enthusiast will always prefer a manual to a dual clutch or automatic. There's more feel and definitely more fun to be able to engage the gear you want when you want it. No need to bang through 5 gears to get to second to hit that corner in the mountains. You can cruise in 6th, hit 2nd for the corner, back to 6th to cruise. Do that with a dual clutch or auto

[Mike_L]

Originally Posted by Twix

I think any true enthusiast will always prefer a manual to a dual clutch or automatic.

You think wrong. Like I said, automatic or bust. And there isn't any way in the world that you could say that I'm not an enthusiast. I've been tuning cars since I was 15, including several to well over 600hp, been through 12 performance driving courses, been racing for years, and had my ASE certification in Engine Performance. There's no metric where I wouldn't be considered an enthusiast. And as such, I'm gonna take the tranny that gets me where I'm going fastest, whether around a track or down the dragstrip, and these days, 99 times out of 100, its the automatic or twin clutch. Theres a reason thats the only way to get most exotics. Manually shifting is slow.