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[ANSWERED] How Does No-Lift-Shift Work

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[ANSWERED] How Does No-Lift-Shift Work

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Old 10-09-2015, 04:48 PM
  #21  
ElCid79
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Originally Posted by BJ67 View Post
Initiate the power shift at 6200, you shouldn't hit the rev limiter. The No lift shift starts to work when you move the shift lever. If you push the clutch in before you pull or push the shift lever it will go right to redline and hit the rev limiter.


Ahh. I will try again doing it this way.
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Old 08-19-2017, 10:47 PM
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Can someone confirm if this feature actually holds the engine speed at the point where the clutch gets pushed in at? For instance, for the purpose of testing it, could you go to 100% pedal in 1st gear, clutch in at 6000rpm, and the engine speed will stay there for some period of time even with the accelerator pedal to 100%?
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Old 08-20-2017, 09:06 AM
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Originally Posted by vtirocz View Post
Can someone confirm if this feature actually holds the engine speed at the point where the clutch gets pushed in at? For instance, for the purpose of testing it, could you go to 100% pedal in 1st gear, clutch in at 6000rpm, and the engine speed will stay there for some period of time even with the accelerator pedal to 100%?
The complete shift procedure (power shift) has to be done for the NLS to work, that's why its called no lift shift. By keeping the car to the floor in any gear and say at 6000 rpm you decide to just push the clutch in with your foot still on the floor, NLS doesn't work because it doesn't detect a shift.

https://www.corvetteforum.com/forums...hift-work.html
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Old 08-20-2017, 10:56 AM
  #24  
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Originally Posted by BJ67 View Post
The complete shift procedure (power shift) has to be done for the NLS to work, that's why its called no lift shift. By keeping the car to the floor in any gear and say at 6000 rpm you decide to just push the clutch in with your foot still on the floor, NLS doesn't work because it doesn't detect a shift.

https://www.corvetteforum.com/forums...hift-work.html
Thanks for the quick response. When the feature is working correctly, does the engine speed hold at the point where the clutch was pushed in at AND gear lever moved to next gear? So if I were to test it out, I could go to 100% accelerator pedal in first gear, clutch in at 6000 AND shift to 2nd (let's say that's all done before engine speed rises to 6300), and the engine speed will stay at some speed less than 6500 (ie. not bouncing off rev limiter) for some period of time with the accelerator pedal pressed to 100% this whole time?

Does anyone have a good video that shows the feature in action?

I have a '17 Camaro SS that supposedly has this feature (as per the chief engineer), but when I execute a no lift shift the engine speed raises to and stays at 6500 RPM, which leads me to believe it's not working as intended on my car.

Last edited by vtirocz; 08-20-2017 at 10:57 AM.
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Old 08-20-2017, 11:41 AM
  #25  
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Originally Posted by vtirocz View Post
Thanks for the quick response. When the feature is working correctly, does the engine speed hold at the point where the clutch was pushed in at AND gear lever moved to next gear? So if I were to test it out, I could go to 100% accelerator pedal in first gear, clutch in at 6000 AND shift to 2nd (let's say that's all done before engine speed rises to 6300), and the engine speed will stay at some speed less than 6500 (ie. not bouncing off rev limiter) for some period of time with the accelerator pedal pressed to 100% this whole time?

Does anyone have a good video that shows the feature in action?

I have a '17 Camaro SS that supposedly has this feature (as per the chief engineer), but when I execute a no lift shift the engine speed raises to and stays at 6500 RPM, which leads me to believe it's not working as intended on my car.
Lets say you perform the power shift when you see the tach needle somewhere after 6k and naturally well before 6500 rpm. The push (blip) of the clutch and the pull/push of the shifter into the next gear are done at the exact time and very quick. I do not know how any could be reading the small tach increments to see if there is any rpm change during such a critical time as you would be only glancing at the tach to make the shift and eyes back to looking out the windshield. The NLS is supposed to hold the rpm at precisely the rpm you performed the pedal blip and the push/pull of the shifter for that split second and as soon as the clutch pedal is back up the system is off. If at any time you change your throttle position from flat on the floor, the system is not activated.

If you could precisely make a power shift at 6k, the engine RPM should hold at 6k and you can hear it in the exhaust as a burble between each NLS power shift. That burble is I believe, fuel and spark interruption by the computer to hold the rpm from spiking.
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Old 09-06-2017, 11:36 PM
  #26  
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Originally Posted by BJ67 View Post
In 2009, the ctsv and the zr1 vette had NLS, the Camaro zl1 had it in 2010. From what I understand, it was developed for the charged cars so the charge boost doesn't drop when you shift.
Do not know if it existed in 08, and not sure what year the naturally aspirated vettes got it.
I know for the Corvette, Launch Control and NLS were only on the 2010+ model years. It was not available on the 09's
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Old 09-08-2017, 04:47 PM
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As for the calibration part.. I speculate that the ECU is momentarily killing ignition/fuel to unload the engine while keeping the throttle open. This is how the quick-shifter on a motorcycle operates and it's generally the same principal for cars. The C7 probably receives some input to kill spark/fuel from the driver the moment the shifter is disengaged from gear.

Last edited by StancyPants; 09-08-2017 at 04:50 PM.
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Old 09-12-2017, 01:47 PM
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Strangely, I could not get the function to work on the track. I loved it in my Gen 5 Camaro 1LE. Worked amazing. I tried for hours in my GS, on the straight at Buttonwillow, and continually bounced off the rev limiter. I ended up doing the old fashioned lift and was rewarded with better times.

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Old 09-17-2017, 10:13 PM
  #29  
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Originally Posted by rb185afm View Post
Strangely, I could not get the function to work on the track. I loved it in my Gen 5 Camaro 1LE. Worked amazing. I tried for hours in my GS, on the straight at Buttonwillow, and continually bounced off the rev limiter. I ended up doing the old fashioned lift and was rewarded with better times.
Same thing here with my GS running in Track Sport 1. Tried it twice and both times it hit the rev limiter and made a very rough shift when I threw it into the next gear. Clutching is definitely more normal feeling but I kept my foot planted on the gas both times.

Actually I just reviewed my PDR video and one time it definitely bumped into the red but the second time it appeared to work?

Last edited by PeteC7; 09-17-2017 at 10:31 PM.
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Old 09-18-2017, 08:05 AM
  #30  
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Originally Posted by rb185afm View Post
Strangely, I could not get the function to work on the track. I loved it in my Gen 5 Camaro 1LE. Worked amazing. I tried for hours in my GS, on the straight at Buttonwillow, and continually bounced off the rev limiter. I ended up doing the old fashioned lift and was rewarded with better times.
Can you state at what rpm you initiated the shift and how you performed the shift. Knowing the throttle was on the floor isn't enough information
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Old 09-18-2017, 08:08 AM
  #31  
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Originally Posted by PeteC7 View Post
Same thing here with my GS running in Track Sport 1. Tried it twice and both times it hit the rev limiter and made a very rough shift when I threw it into the next gear. Clutching is definitely more normal feeling but I kept my foot planted on the gas both times.

Actually I just reviewed my PDR video and one time it definitely bumped into the red but the second time it appeared to work?
Same question, at what rpm did you initiate the shift and exactly how did you perform that shift. Even if you perform a power shift 3 to 5 hundred RPM before the red line you shouldn't hit the redline
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Old 09-18-2017, 12:20 PM
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The first one hits redline, the second one seems better but the revs did still seem to increase. The process was gas pedal to the floor and at redline press the clutch in and shift quickly.


Last edited by PeteC7; 09-18-2017 at 12:22 PM.
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Old 09-18-2017, 01:04 PM
  #33  
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Originally Posted by PeteC7 View Post
The first one hits redline, the second one seems better but the revs did still seem to increase. The process was gas pedal to the floor and at redline press the clutch in and shift quickly.

https://vimeo.com/234348074
First of all you don't do a no lift shift /power shift at redline. The shift has to be initiated just before redline because of the time it takes to perform a true power shift. Also the tach is always behind the actual RPM, so if you initiate the shift at redline, you are already hitting the ref limiter at 6600 RPM. Just one more thing, listening to your shifts, they are way to slow. Try doing a super fast shift and blip of the clutch at exactly the same time at 6200 rpm, you should not hit the rev limiter even with out NLS
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Old 09-18-2017, 01:18 PM
  #34  
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Default power shifting

Turn up the speakers and listen to how quick and violent a power shift is, if need a password to open the dropbox file its 567521.

https://www.dropbox.com/scl/fi/2umas..._RU6bUjBs&sm=1
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Old 11-14-2017, 09:15 PM
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This same question was just answered on the 6th gen camaro forum in the similar "Ask Al" (chief engineer for Camaro platform) subforum:

http://www.camaro6.com/forums/showthread.php?t=513327

That provides more detail that I thought some folks might be interested in. I suspect the features are tuned very similarly between the Camaro and Corvette platforms.
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Old 11-22-2017, 09:45 PM
  #36  
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Good post... I thought Rev Match had to be on. It's a little unnerving to trust the system, thinking I'm going to blow the engine
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Old 09-05-2018, 01:52 PM
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Hate to revive a post from last year but anyone know the parameters for the NLS on the 17 non z51 cars? I finally got my break in done and decided to try the NLS. I purposely shifted at 6k rpm. My original impression was that I would see the RPMís hold at 6k. They did not. I am pretty quick in power shifting so was in 2nd gear by the time it hit 6300 RPM but it damn sure did not hold at 6k RPMís. Then I switched to track with competitive driving mode. Same thing. I slammed 2nd gear and saw the tach hit about 6300 rpm...point being it did not hold at 6k. In vtiroczís link above GM says different car combinations have different enable RPMís and different targets. Anyone know what those numbers are for the C7?


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Old 09-05-2018, 03:11 PM
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Originally Posted by cerino2000 View Post
Hate to revive a post from last year but anyone know the parameters for the NLS on the 17 non z51 cars? I finally got my break in done and decided to try the NLS. I purposely shifted at 6k rpm. My original impression was that I would see the RPM’s hold at 6k. They did not. I am pretty quick in power shifting so was in 2nd gear by the time it hit 6300 RPM but it damn sure did not hold at 6k RPM’s. Then I switched to track with competitive driving mode. Same thing. I slammed 2nd gear and saw the tach hit about 6300 rpm...point being it did not hold at 6k. In vtirocz’s link above GM says different car combinations have different enable RPM’s and different targets. Anyone know what those numbers are for the C7?



Here is the Camaro info, never seen it for the vettes. I would use the SSLT1 or the SS1LE for reference
https://www.camaro6.com/forums/showthread.php?t=513327

Last edited by BJ67; 09-05-2018 at 03:15 PM.
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