M7 or A8?
#61
#62
Lifetime NCM Member #2497
Someone correct me if I'm wrong, but the A8 doesn't have the shudder issue on 19s anymore right?
OP - my understanding is sticking a Range AFM disabler on it is all you'd want to consider for a 19 A8.
I enjoy paddle shifting mine even though the response is a bit slow. Honestly, though, my biggest complaint is that Chevy didn't include some way to enable performance shift mode indefinitely. That's when the A8 is the most fun.
OP - my understanding is sticking a Range AFM disabler on it is all you'd want to consider for a 19 A8.
I enjoy paddle shifting mine even though the response is a bit slow. Honestly, though, my biggest complaint is that Chevy didn't include some way to enable performance shift mode indefinitely. That's when the A8 is the most fun.
#63
Racer
Thread Starter
Member Since: Sep 2000
Location: The Land of Enchantment
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2022 C7 of the Year Finalist - Modified
Finalist 2020 C7 of the Year -- Modified
For me, I put this debate to rest yesterday when I bought a new Z06/7 with the M7. I love the manual in this car, the clutch feel is very similar to my SS 1LE. Surprisingly I actually prefer the shifts in my 1LE, they are more notchy and I can feel when the car is in gear. A couple of times in my new Z, I thought I was in 1st, but it wasn't. Fortunately the big gear indicator on the HUD saved me from looking like the idiot who can't drive his 6-figure sports car. The 7'th gear is going to take a bit of getting used to also. More than once I ended up in 7th when I was going to 5th. All quirks one needs to get accustomed to with a new car. All-in-all, I don't regret trading my 1LE in on this Z. She is leaps and bounds a better car than the Camaro, and I loved that Camaro.
Last edited by twiget; 05-12-2019 at 09:51 PM.
#64
#65
For me, I put this debate to rest yesterday when I bought a new Z06/7 with the M7. I love the manual in this car, the clutch feel is very similar to my SS 1LE. Surprisingly I actually prefer the shifts in my 1LE, they are more notchy and I can feel when the car is in gear. A couple of times in my new Z, I thought I was in 1st, but it wasn't. Fortunately the big gear indicator on the HUD saved me from looking like the idiot who can't drive his 6-figure sports car. The 7'th gear is going to take a bit of getting used to also. More than once I ended up in 7th when I was going to 5th. All quirks one needs to get accustomed to with a new car. All-in-all, I don't regret trading my 1LE in on this Z. She is leaps and bounds a better car than the Camaro, and I loved that Camaro.
#66
Safety Car
I know....I know.....I kick myself all the time for selling it, but I bought the car for $70K, drove it for 4 years and put 65k miles on it and it sold in two hours for $72k. I think I got a pretty good run with it and long term storage was going to be an issue. Everyone that knows cars tells me I sold the unicorn......it also had no sun roof. The funny part was that the dealership I ordered it from originally made a mistake and had ordered an A6, then tried to tell me it was going to be more valuable.....I told them that I wanted what I ordered and would not back down and I waited another month for the right car. Btw mine was the same color Storm Gray but without the yellow calipers.
Last edited by Road machine; 05-13-2019 at 11:18 AM.
#67
Le Mans Master
Member Since: Apr 2005
Location: West Burbs of Chicago IL
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I had a manual, than an A8. Regretted it for 3 years. Went back to the M7 last April and love it. IF you enjoy a manual, do not compromise. Get a manual.
The following users liked this post:
Z0HS1CK (05-13-2019)
#68
I wouldn't say the A8 is trash, but I will quickly admit that it is some what of a GM slush box in normal operating conditions, except when you are in a full throttle application....the shifts are instantaneous then. The ZF transmission in the Chrysler products is light years ahead in the torque converter/transmission drive train design and operation in all respects.
#69
Racer
I had a '17 A8 Z07 and all the comments so far are fairly aligned to my experience. When I tracked the same car at Ron Fellows, it overheated, and they told me to use "taller gears". Unacceptable if you race your car. When I drove it aggressively, the shifts were sluggish, unless I was in a place I could literally thrash on it and the A8 gods allowed it to go into performance shift mode. Make that a selectable option and it's a different car. That is when the A8 shines. The "no-thinking" about shifting was nice in traffic. Holding in the downshift paddle when slowing down has the engine computer find the lowest gear the transmission can handle and that shift always sounds/feels great! That's a feature I stumbled on and wasn't aware the car had until I did it. The A8 is the faster car for the average driver, like me.
I would get an A8 again if GM did two things:
1) fix the track overheating issue (some here say they have in the 2019)
2) make the performance shift mode a selectable option.
I am currently looking at an MT Z07 and am looking forward to being more in direct control of the car. Not looking forward to heavy traffic situations, but if that's the worst of it, I'm good.
I would get an A8 again if GM did two things:
1) fix the track overheating issue (some here say they have in the 2019)
2) make the performance shift mode a selectable option.
I am currently looking at an MT Z07 and am looking forward to being more in direct control of the car. Not looking forward to heavy traffic situations, but if that's the worst of it, I'm good.
Last edited by Pizz; 05-14-2019 at 02:00 PM. Reason: correction
The following users liked this post:
Z0HS1CK (05-14-2019)
#70
I had a '17 A8 Z07 and all the comments so far are fairly aligned to my experience. When I tracked the same car at Ron Fellows, it overheated, and they told me to use "taller gears". Unacceptable if you race your car. When I drove it aggressively, the shifts were sluggish, unless I was in a place I could literally thrash on it and the A8 gods allowed it to go into performance shift mode. Make that a selectable option and it's a different car. That is when the A8 shines. The "no-thinking" about shifting was nice in traffic. Holding in the downshift paddle when slowing down has the engine find the lowest gear the transmission can handle and that shift always sounds/feels great! That's a feature I stumbled on and wasn't aware the car had until I did it. The A8 is the faster car for the average driver, like me.
I would get an A8 again if GM did two things:
1) fix the track overheating issue (some here say they have in the 2019)
2) make the performance shift mode a selectable option.
I am currently looking at an MT Z07 and am looking forward to being more in direct control of the car. Not looking forward to heavy traffic situations, but if that's the worst of it, I'm good.
I would get an A8 again if GM did two things:
1) fix the track overheating issue (some here say they have in the 2019)
2) make the performance shift mode a selectable option.
I am currently looking at an MT Z07 and am looking forward to being more in direct control of the car. Not looking forward to heavy traffic situations, but if that's the worst of it, I'm good.
For those who use these cars for pleasure drives, I think the manual is always the best route. If you like taking the car to the strip, a8 would be better.
I got the manual because I have 2 other cars to use so it's not a daily. And to me it's more exciting to drive. And I dont have to worry about overheating lmao.
#71
I owned a 2015 stingray with an auto and now have a 2016 zo6 m7.. My opinion is that it depends on YOU and what YOU enjoy. For me, I’m enjoying the m7 much more than the a8 just because it brings you in to the driving experience much more. I like to be actively engaged in driving and the zo6 is already an engaging more so for me the m7 just tops it off.
Plus, I had issues with my a8 so that was a big turn off. And before anyone says that it’s apples/oranges to compare the stingray to a z, I’ve driven two zo6’s with the a8 so I’ve at least given it a shot.
All this being said, if track times are what you’re after then go for the a8..
Plus, I had issues with my a8 so that was a big turn off. And before anyone says that it’s apples/oranges to compare the stingray to a z, I’ve driven two zo6’s with the a8 so I’ve at least given it a shot.
All this being said, if track times are what you’re after then go for the a8..
#72
I owned a 2015 stingray with an auto and now have a 2016 zo6 m7.. My opinion is that it depends on YOU and what YOU enjoy. For me, I’m enjoying the m7 much more than the a8 just because it brings you in to the driving experience much more. I like to be actively engaged in driving and the zo6 is already an engaging more so for me the m7 just tops it off.
Plus, I had issues with my a8 so that was a big turn off. And before anyone says that it’s apples/oranges to compare the stingray to a z, I’ve driven two zo6’s with the a8 so I’ve at least given it a shot.
All this being said, if drag times are what you’re after then go for the a8..
Plus, I had issues with my a8 so that was a big turn off. And before anyone says that it’s apples/oranges to compare the stingray to a z, I’ve driven two zo6’s with the a8 so I’ve at least given it a shot.
All this being said, if drag times are what you’re after then go for the a8..
Anything else, IMHO, M7. Roll racing, weekend fun, road course, autox etc.
#74
Safety Car
I had a '17 A8 Z07 and all the comments so far are fairly aligned to my experience. When I tracked the same car at Ron Fellows, it overheated, and they told me to use "taller gears". Unacceptable if you race your car. When I drove it aggressively, the shifts were sluggish, unless I was in a place I could literally thrash on it and the A8 gods allowed it to go into performance shift mode. Make that a selectable option and it's a different car. That is when the A8 shines. The "no-thinking" about shifting was nice in traffic. Holding in the downshift paddle when slowing down has the engine computer find the lowest gear the transmission can handle and that shift always sounds/feels great! That's a feature I stumbled on and wasn't aware the car had until I did it. The A8 is the faster car for the average driver, like me.
I would get an A8 again if GM did two things:
1) fix the track overheating issue (some here say they have in the 2019)
2) make the performance shift mode a selectable option.
I am currently looking at an MT Z07 and am looking forward to being more in direct control of the car. Not looking forward to heavy traffic situations, but if that's the worst of it, I'm good.
I would get an A8 again if GM did two things:
1) fix the track overheating issue (some here say they have in the 2019)
2) make the performance shift mode a selectable option.
I am currently looking at an MT Z07 and am looking forward to being more in direct control of the car. Not looking forward to heavy traffic situations, but if that's the worst of it, I'm good.
#75
Racer
I did the spring mountain course last March, so I think they were 2017’s. performance mode shifting can’t be selected by picking a track mode (unless they changed it for 2019). The computer enables it when it sees a driver pushing the car hard on the throttle. You get an alert on the main display that says “performance shift enabled”.
#76
Manual has always been my preferred choice. 13 cars total over the years with only 2 being automatics and were used for daily driving/beater duties. They are great for when you don't feel like "driving" (rare for me) but they do serve their purpose. For sports cars though, I always go manual. It's the thrill, the engagement, being one with the car that I can't get enough of.
#77
For me, I put this debate to rest yesterday when I bought a new Z06/7 with the M7. I love the manual in this car, the clutch feel is very similar to my SS 1LE. Surprisingly I actually prefer the shifts in my 1LE, they are more notchy and I can feel when the car is in gear. A couple of times in my new Z, I thought I was in 1st, but it wasn't. Fortunately the big gear indicator on the HUD saved me from looking like the idiot who can't drive his 6-figure sports car. The 7'th gear is going to take a bit of getting used to also. More than once I ended up in 7th when I was going to 5th. All quirks one needs to get accustomed to with a new car. All-in-all, I don't regret trading my 1LE in on this Z. She is leaps and bounds a better car than the Camaro, and I loved that Camaro.
#78
Safety Car
I did the spring mountain course last March, so I think they were 2017’s. performance mode shifting can’t be selected by picking a track mode (unless they changed it for 2019). The computer enables it when it sees a driver pushing the car hard on the throttle. You get an alert on the main display that says “performance shift enabled”.
This may help solve any questions..
Quote:
dmhines asked:
Why does the time between depressing the paddle in manual mode and the Automatic Transmission shifting seem so long. Why can't it be instantaneous?
dmhines asked:
Why does the time between depressing the paddle in manual mode and the Automatic Transmission shifting seem so long. Why can't it be instantaneous?
Quote:
Tadge answered:
First of all, we on Team Corvette want to wish everyone in the Corvette community and on the Corvette Forum a wonderful holiday and a safe and happy new year!
Now on to the answer:
Although shift speeds have been a priority in racing for a long time, it is a relatively new focus in the mass production auto industry. For decades we had basically two transmission choices; a traditional manual transmission where the time to shift was 100% dependent on the driver’s skill level, and a torque converter automatic where the vehicle hardware and calibration determined the shift timing and speed. The main focus on the automatics was a smooth shift with little driveline or customer disturbance. Yes, there were niche products that featured different set ups, so pardon me for the generalization.
Some performance cars started to offer automated manual transmissions that used a traditional clutch but did the work of shifting robotically, but my experience with those early units was that they were slow and lacked the finesse of a well-shifted manual driven by a skilled driver. Over time the shift quality and speed was improved and manufacturers started talking about shift times as an important performance vehicle characteristic. For the most part auto makers have moved away from automated manuals and use sophisticated planetary automatics or DCT’s to get the best shift speed and quality. This question focuses on shift speed, so I will leave the pros and cons of the two automatic transmission types for another day.
So why can’t down shifts be instantaneous? Well, there is the transmission hardware side that faces the physical challenge of transferring the torque from one set of gears to another set of gears. That is the time most manufacturers quote when discussing shift times. Those times have been improved over the years to very small fractions of a second and the Corvette is competitive with the best on that score. To be honest, we have put a higher priority on upshifts because they occur while accelerating and will contribute faster lap times. Downshifts typically occur when off-throttle and on the brakes, so a slower shift is far less likely to affect lap times. Regardless, up or down, our 8-speed automatic transmission is capable of extremely fast shift speeds.
The paddle shifters on Corvette are controlled by on-board computers just like many other functions on the car. They are “intelligent” devices that seek to improve the safety and controllability of the car. When the driver requests a downshift, the car does not blindly obey (the same is true for throttle inputs). It checks a multitude of parameters to verify that a shift can be done safely, without risk of damage to the car and without upsetting the vehicle dynamics. The control modules work to match the speed and torque of the engine to the future gear state. Note that there are a number of ECUs (Electronic Control Units) involved communicating in a coordinated way across an on-vehicle network, not just a computation done in a single processor. The larger the engine, the more inertia and the more challenging perfect matching is. I’m sure you know that an abrupt shift and resulting torque spike while cornering quickly can unsettle the car, so the algorithms for shifting will take that into account. In addition to how the car is being driven, ambient conditions, driver mode selected and other factors are taken into account. Even the break-in state of the transmission matters. Over time the transmission actually learns about itself and seeks to improve shift performance. All this intelligence takes computational time by the on-board processors. The throughput of those processors is dependent on the workload at the time of the shift, so the latency from shift command to shift execution can vary a bit.
All manufacturers are working to improve the shift speed and quality of their transmissions. I foresee ongoing improvement in this area.
One last side note: Some companies do something that we do not do. They move the tachometer needle to the new rpm on a shift faster than the engine actually achieves it. This bit of electronic trickery improves the perception of shift speed without actually changing it. Although it seems to be effective, we don't do it because it is inconsistent with our philosophy on Corvette to convey the most accurate information possible in our cluster displays.
Tadge answered:
First of all, we on Team Corvette want to wish everyone in the Corvette community and on the Corvette Forum a wonderful holiday and a safe and happy new year!
Now on to the answer:
Although shift speeds have been a priority in racing for a long time, it is a relatively new focus in the mass production auto industry. For decades we had basically two transmission choices; a traditional manual transmission where the time to shift was 100% dependent on the driver’s skill level, and a torque converter automatic where the vehicle hardware and calibration determined the shift timing and speed. The main focus on the automatics was a smooth shift with little driveline or customer disturbance. Yes, there were niche products that featured different set ups, so pardon me for the generalization.
Some performance cars started to offer automated manual transmissions that used a traditional clutch but did the work of shifting robotically, but my experience with those early units was that they were slow and lacked the finesse of a well-shifted manual driven by a skilled driver. Over time the shift quality and speed was improved and manufacturers started talking about shift times as an important performance vehicle characteristic. For the most part auto makers have moved away from automated manuals and use sophisticated planetary automatics or DCT’s to get the best shift speed and quality. This question focuses on shift speed, so I will leave the pros and cons of the two automatic transmission types for another day.
So why can’t down shifts be instantaneous? Well, there is the transmission hardware side that faces the physical challenge of transferring the torque from one set of gears to another set of gears. That is the time most manufacturers quote when discussing shift times. Those times have been improved over the years to very small fractions of a second and the Corvette is competitive with the best on that score. To be honest, we have put a higher priority on upshifts because they occur while accelerating and will contribute faster lap times. Downshifts typically occur when off-throttle and on the brakes, so a slower shift is far less likely to affect lap times. Regardless, up or down, our 8-speed automatic transmission is capable of extremely fast shift speeds.
The paddle shifters on Corvette are controlled by on-board computers just like many other functions on the car. They are “intelligent” devices that seek to improve the safety and controllability of the car. When the driver requests a downshift, the car does not blindly obey (the same is true for throttle inputs). It checks a multitude of parameters to verify that a shift can be done safely, without risk of damage to the car and without upsetting the vehicle dynamics. The control modules work to match the speed and torque of the engine to the future gear state. Note that there are a number of ECUs (Electronic Control Units) involved communicating in a coordinated way across an on-vehicle network, not just a computation done in a single processor. The larger the engine, the more inertia and the more challenging perfect matching is. I’m sure you know that an abrupt shift and resulting torque spike while cornering quickly can unsettle the car, so the algorithms for shifting will take that into account. In addition to how the car is being driven, ambient conditions, driver mode selected and other factors are taken into account. Even the break-in state of the transmission matters. Over time the transmission actually learns about itself and seeks to improve shift performance. All this intelligence takes computational time by the on-board processors. The throughput of those processors is dependent on the workload at the time of the shift, so the latency from shift command to shift execution can vary a bit.
All manufacturers are working to improve the shift speed and quality of their transmissions. I foresee ongoing improvement in this area.
One last side note: Some companies do something that we do not do. They move the tachometer needle to the new rpm on a shift faster than the engine actually achieves it. This bit of electronic trickery improves the perception of shift speed without actually changing it. Although it seems to be effective, we don't do it because it is inconsistent with our philosophy on Corvette to convey the most accurate information possible in our cluster displays.
#79
Le Mans Master
Not sure that they would still have 2017s a year later. I know the car I drove in February was a 2019. Not sure whether or not I was in performance shifting, but I never ever felt any delay at all, in either direction.When I first got my 2019 A8 I did notice a bad delay in shifting. I was even thinking I had made a mistake. But once the car was broken in, the delay went away completely. I found out later that the transmission is programmed to delay shifts until the transmission is broken in to protect the life of the trans. I always drive in manual mode and love it. The same feeling of control as the M6 I used to have, but when I hit traffic my left leg does not fall off. I do have to get used to the paddles, as sometimes I hit the wrong one, but not often enough to matter. The only thing I would change is I would add the ability to shift with the shifter. My wifes CLK had that ability a push to the left side would down shift and one to the right would up shift. It also had the paddles but using the shifter gives you even more of the manual feel.
This may help solve any questions..
Quote:
dmhines asked:
Why does the time between depressing the paddle in manual mode and the Automatic Transmission shifting seem so long. Why can't it be instantaneous?
Quote:
Tadge answered:
First of all, we on Team Corvette want to wish everyone in the Corvette community and on the Corvette Forum a wonderful holiday and a safe and happy new year!
Now on to the answer:
Although shift speeds have been a priority in racing for a long time, it is a relatively new focus in the mass production auto industry. For decades we had basically two transmission choices; a traditional manual transmission where the time to shift was 100% dependent on the driver’s skill level, and a torque converter automatic where the vehicle hardware and calibration determined the shift timing and speed. The main focus on the automatics was a smooth shift with little driveline or customer disturbance. Yes, there were niche products that featured different set ups, so pardon me for the generalization.
Some performance cars started to offer automated manual transmissions that used a traditional clutch but did the work of shifting robotically, but my experience with those early units was that they were slow and lacked the finesse of a well-shifted manual driven by a skilled driver. Over time the shift quality and speed was improved and manufacturers started talking about shift times as an important performance vehicle characteristic. For the most part auto makers have moved away from automated manuals and use sophisticated planetary automatics or DCT’s to get the best shift speed and quality. This question focuses on shift speed, so I will leave the pros and cons of the two automatic transmission types for another day.
So why can’t down shifts be instantaneous? Well, there is the transmission hardware side that faces the physical challenge of transferring the torque from one set of gears to another set of gears. That is the time most manufacturers quote when discussing shift times. Those times have been improved over the years to very small fractions of a second and the Corvette is competitive with the best on that score. To be honest, we have put a higher priority on upshifts because they occur while accelerating and will contribute faster lap times. Downshifts typically occur when off-throttle and on the brakes, so a slower shift is far less likely to affect lap times. Regardless, up or down, our 8-speed automatic transmission is capable of extremely fast shift speeds.
The paddle shifters on Corvette are controlled by on-board computers just like many other functions on the car. They are “intelligent” devices that seek to improve the safety and controllability of the car. When the driver requests a downshift, the car does not blindly obey (the same is true for throttle inputs). It checks a multitude of parameters to verify that a shift can be done safely, without risk of damage to the car and without upsetting the vehicle dynamics. The control modules work to match the speed and torque of the engine to the future gear state. Note that there are a number of ECUs (Electronic Control Units) involved communicating in a coordinated way across an on-vehicle network, not just a computation done in a single processor. The larger the engine, the more inertia and the more challenging perfect matching is. I’m sure you know that an abrupt shift and resulting torque spike while cornering quickly can unsettle the car, so the algorithms for shifting will take that into account. In addition to how the car is being driven, ambient conditions, driver mode selected and other factors are taken into account. Even the break-in state of the transmission matters. Over time the transmission actually learns about itself and seeks to improve shift performance. All this intelligence takes computational time by the on-board processors. The throughput of those processors is dependent on the workload at the time of the shift, so the latency from shift command to shift execution can vary a bit.
All manufacturers are working to improve the shift speed and quality of their transmissions. I foresee ongoing improvement in this area.
One last side note: Some companies do something that we do not do. They move the tachometer needle to the new rpm on a shift faster than the engine actually achieves it. This bit of electronic trickery improves the perception of shift speed without actually changing it. Although it seems to be effective, we don't do it because it is inconsistent with our philosophy on Corvette to convey the most accurate information possible in our cluster displays.
This may help solve any questions..
Quote:
dmhines asked:
Why does the time between depressing the paddle in manual mode and the Automatic Transmission shifting seem so long. Why can't it be instantaneous?
Quote:
Tadge answered:
First of all, we on Team Corvette want to wish everyone in the Corvette community and on the Corvette Forum a wonderful holiday and a safe and happy new year!
Now on to the answer:
Although shift speeds have been a priority in racing for a long time, it is a relatively new focus in the mass production auto industry. For decades we had basically two transmission choices; a traditional manual transmission where the time to shift was 100% dependent on the driver’s skill level, and a torque converter automatic where the vehicle hardware and calibration determined the shift timing and speed. The main focus on the automatics was a smooth shift with little driveline or customer disturbance. Yes, there were niche products that featured different set ups, so pardon me for the generalization.
Some performance cars started to offer automated manual transmissions that used a traditional clutch but did the work of shifting robotically, but my experience with those early units was that they were slow and lacked the finesse of a well-shifted manual driven by a skilled driver. Over time the shift quality and speed was improved and manufacturers started talking about shift times as an important performance vehicle characteristic. For the most part auto makers have moved away from automated manuals and use sophisticated planetary automatics or DCT’s to get the best shift speed and quality. This question focuses on shift speed, so I will leave the pros and cons of the two automatic transmission types for another day.
So why can’t down shifts be instantaneous? Well, there is the transmission hardware side that faces the physical challenge of transferring the torque from one set of gears to another set of gears. That is the time most manufacturers quote when discussing shift times. Those times have been improved over the years to very small fractions of a second and the Corvette is competitive with the best on that score. To be honest, we have put a higher priority on upshifts because they occur while accelerating and will contribute faster lap times. Downshifts typically occur when off-throttle and on the brakes, so a slower shift is far less likely to affect lap times. Regardless, up or down, our 8-speed automatic transmission is capable of extremely fast shift speeds.
The paddle shifters on Corvette are controlled by on-board computers just like many other functions on the car. They are “intelligent” devices that seek to improve the safety and controllability of the car. When the driver requests a downshift, the car does not blindly obey (the same is true for throttle inputs). It checks a multitude of parameters to verify that a shift can be done safely, without risk of damage to the car and without upsetting the vehicle dynamics. The control modules work to match the speed and torque of the engine to the future gear state. Note that there are a number of ECUs (Electronic Control Units) involved communicating in a coordinated way across an on-vehicle network, not just a computation done in a single processor. The larger the engine, the more inertia and the more challenging perfect matching is. I’m sure you know that an abrupt shift and resulting torque spike while cornering quickly can unsettle the car, so the algorithms for shifting will take that into account. In addition to how the car is being driven, ambient conditions, driver mode selected and other factors are taken into account. Even the break-in state of the transmission matters. Over time the transmission actually learns about itself and seeks to improve shift performance. All this intelligence takes computational time by the on-board processors. The throughput of those processors is dependent on the workload at the time of the shift, so the latency from shift command to shift execution can vary a bit.
All manufacturers are working to improve the shift speed and quality of their transmissions. I foresee ongoing improvement in this area.
One last side note: Some companies do something that we do not do. They move the tachometer needle to the new rpm on a shift faster than the engine actually achieves it. This bit of electronic trickery improves the perception of shift speed without actually changing it. Although it seems to be effective, we don't do it because it is inconsistent with our philosophy on Corvette to convey the most accurate information possible in our cluster displays.
#80
Drifting
Not sure that they would still have 2017s a year later. I know the car I drove in February was a 2019. Not sure whether or not I was in performance shifting, but I never ever felt any delay at all, in either direction.When I first got my 2019 A8 I did notice a bad delay in shifting. I was even thinking I had made a mistake. But once the car was broken in, the delay went away completely. I found out later that the transmission is programmed to delay shifts until the transmission is broken in to protect the life of the trans. I always drive in manual mode and love it. The same feeling of control as the M6 I used to have, but when I hit traffic my left leg does not fall off. I do have to get used to the paddles, as sometimes I hit the wrong one, but not often enough to matter. The only thing I would change is I would add the ability to shift with the shifter. My wifes CLK had that ability a push to the left side would down shift and one to the right would up shift. It also had the paddles but using the shifter gives you even more of the manual feel.
This may help solve any questions..
Quote:
dmhines asked:
Why does the time between depressing the paddle in manual mode and the Automatic Transmission shifting seem so long. Why can't it be instantaneous?
Quote:
Tadge answered:
First of all, we on Team Corvette want to wish everyone in the Corvette community and on the Corvette Forum a wonderful holiday and a safe and happy new year!
Now on to the answer:
Although shift speeds have been a priority in racing for a long time, it is a relatively new focus in the mass production auto industry. For decades we had basically two transmission choices; a traditional manual transmission where the time to shift was 100% dependent on the driver’s skill level, and a torque converter automatic where the vehicle hardware and calibration determined the shift timing and speed. The main focus on the automatics was a smooth shift with little driveline or customer disturbance. Yes, there were niche products that featured different set ups, so pardon me for the generalization.
Some performance cars started to offer automated manual transmissions that used a traditional clutch but did the work of shifting robotically, but my experience with those early units was that they were slow and lacked the finesse of a well-shifted manual driven by a skilled driver. Over time the shift quality and speed was improved and manufacturers started talking about shift times as an important performance vehicle characteristic. For the most part auto makers have moved away from automated manuals and use sophisticated planetary automatics or DCT’s to get the best shift speed and quality. This question focuses on shift speed, so I will leave the pros and cons of the two automatic transmission types for another day.
So why can’t down shifts be instantaneous? Well, there is the transmission hardware side that faces the physical challenge of transferring the torque from one set of gears to another set of gears. That is the time most manufacturers quote when discussing shift times. Those times have been improved over the years to very small fractions of a second and the Corvette is competitive with the best on that score. To be honest, we have put a higher priority on upshifts because they occur while accelerating and will contribute faster lap times. Downshifts typically occur when off-throttle and on the brakes, so a slower shift is far less likely to affect lap times. Regardless, up or down, our 8-speed automatic transmission is capable of extremely fast shift speeds.
The paddle shifters on Corvette are controlled by on-board computers just like many other functions on the car. They are “intelligent” devices that seek to improve the safety and controllability of the car. When the driver requests a downshift, the car does not blindly obey (the same is true for throttle inputs). It checks a multitude of parameters to verify that a shift can be done safely, without risk of damage to the car and without upsetting the vehicle dynamics. The control modules work to match the speed and torque of the engine to the future gear state. Note that there are a number of ECUs (Electronic Control Units) involved communicating in a coordinated way across an on-vehicle network, not just a computation done in a single processor. The larger the engine, the more inertia and the more challenging perfect matching is. I’m sure you know that an abrupt shift and resulting torque spike while cornering quickly can unsettle the car, so the algorithms for shifting will take that into account. In addition to how the car is being driven, ambient conditions, driver mode selected and other factors are taken into account. Even the break-in state of the transmission matters. Over time the transmission actually learns about itself and seeks to improve shift performance. All this intelligence takes computational time by the on-board processors. The throughput of those processors is dependent on the workload at the time of the shift, so the latency from shift command to shift execution can vary a bit.
All manufacturers are working to improve the shift speed and quality of their transmissions. I foresee ongoing improvement in this area.
One last side note: Some companies do something that we do not do. They move the tachometer needle to the new rpm on a shift faster than the engine actually achieves it. This bit of electronic trickery improves the perception of shift speed without actually changing it. Although it seems to be effective, we don't do it because it is inconsistent with our philosophy on Corvette to convey the most accurate information possible in our cluster displays.
This may help solve any questions..
Quote:
dmhines asked:
Why does the time between depressing the paddle in manual mode and the Automatic Transmission shifting seem so long. Why can't it be instantaneous?
Quote:
Tadge answered:
First of all, we on Team Corvette want to wish everyone in the Corvette community and on the Corvette Forum a wonderful holiday and a safe and happy new year!
Now on to the answer:
Although shift speeds have been a priority in racing for a long time, it is a relatively new focus in the mass production auto industry. For decades we had basically two transmission choices; a traditional manual transmission where the time to shift was 100% dependent on the driver’s skill level, and a torque converter automatic where the vehicle hardware and calibration determined the shift timing and speed. The main focus on the automatics was a smooth shift with little driveline or customer disturbance. Yes, there were niche products that featured different set ups, so pardon me for the generalization.
Some performance cars started to offer automated manual transmissions that used a traditional clutch but did the work of shifting robotically, but my experience with those early units was that they were slow and lacked the finesse of a well-shifted manual driven by a skilled driver. Over time the shift quality and speed was improved and manufacturers started talking about shift times as an important performance vehicle characteristic. For the most part auto makers have moved away from automated manuals and use sophisticated planetary automatics or DCT’s to get the best shift speed and quality. This question focuses on shift speed, so I will leave the pros and cons of the two automatic transmission types for another day.
So why can’t down shifts be instantaneous? Well, there is the transmission hardware side that faces the physical challenge of transferring the torque from one set of gears to another set of gears. That is the time most manufacturers quote when discussing shift times. Those times have been improved over the years to very small fractions of a second and the Corvette is competitive with the best on that score. To be honest, we have put a higher priority on upshifts because they occur while accelerating and will contribute faster lap times. Downshifts typically occur when off-throttle and on the brakes, so a slower shift is far less likely to affect lap times. Regardless, up or down, our 8-speed automatic transmission is capable of extremely fast shift speeds.
The paddle shifters on Corvette are controlled by on-board computers just like many other functions on the car. They are “intelligent” devices that seek to improve the safety and controllability of the car. When the driver requests a downshift, the car does not blindly obey (the same is true for throttle inputs). It checks a multitude of parameters to verify that a shift can be done safely, without risk of damage to the car and without upsetting the vehicle dynamics. The control modules work to match the speed and torque of the engine to the future gear state. Note that there are a number of ECUs (Electronic Control Units) involved communicating in a coordinated way across an on-vehicle network, not just a computation done in a single processor. The larger the engine, the more inertia and the more challenging perfect matching is. I’m sure you know that an abrupt shift and resulting torque spike while cornering quickly can unsettle the car, so the algorithms for shifting will take that into account. In addition to how the car is being driven, ambient conditions, driver mode selected and other factors are taken into account. Even the break-in state of the transmission matters. Over time the transmission actually learns about itself and seeks to improve shift performance. All this intelligence takes computational time by the on-board processors. The throughput of those processors is dependent on the workload at the time of the shift, so the latency from shift command to shift execution can vary a bit.
All manufacturers are working to improve the shift speed and quality of their transmissions. I foresee ongoing improvement in this area.
One last side note: Some companies do something that we do not do. They move the tachometer needle to the new rpm on a shift faster than the engine actually achieves it. This bit of electronic trickery improves the perception of shift speed without actually changing it. Although it seems to be effective, we don't do it because it is inconsistent with our philosophy on Corvette to convey the most accurate information possible in our cluster displays.
Actually I'll rephrase that, since "fast" is subjective. If you want a shift to happen as soon as the car receives driver input.
Last edited by Toddiesel; 05-21-2019 at 07:38 AM.