01-16-2017, 12:21 PM | #1 |
Drives: 2SS & GT Premium Join Date: Jan 2017
Location: Southern Cali
Posts: 100
|
No lift shift (manual trans) is making my car backfire, am I doing it wrong?
2017 SS manual transmission. All stock, 2000 miles, always run premium gas.
So I went to the drag strip last week and tried no lift shift for the first time. While it did seem to function and do it's job correctly, every time I would use it, right when I would shift I would get a loud backfire from the car. I thought I was doing it wrong so I stopped. I tried it again when I went back to the drag strip this weekend, and same thing, a loud backfire when I shift. I have the car in competition mode, I am shifting at around 6200-6300 rpm (not hitting the rev limiter), and I am holding the gas to the floor for the whole pass. Not sure what I am doing wrong? But I am afraid of breaking something with the car backfiring like this. When i shift normally, I never get these loud backfire like sounds. Has anybody else tried this no lift shift feature? Last edited by SS2017; 03-29-2017 at 01:45 PM. |
01-16-2017, 03:23 PM | #2 |
Drives: '17 2SS convertible'20 Yukon Denali Join Date: Nov 2011
Location: Cedar Park, Texas
Posts: 2,931
|
I have the A8 and get the same thing when it shifts under full throttle (lower gears). Several people have posted on here that it is programmed that way in the ECU. Fine with me.
__________________
Richard
2017 2SS SIM convertible, A8, NPP, MRC, 56R wheels, GM CAI, Diode Dynamics Side Markers Delivered: 08/15/2016 #TeamBeckyD |
01-16-2017, 03:31 PM | #3 |
Blessed ❤️
Drives: 2017 1LT RS I4 Join Date: Sep 2016
Location: Indiana
Posts: 2,577
|
__________________
2017 1LT RS I4 A8 BLACK ON BLACK
Kindness and compassion #OthersFirst |
01-16-2017, 03:41 PM | #4 | |
マスタング = 遅い
Drives: 2017 Chevrolet Camaro SS 1LE Join Date: Aug 2015
Location: Florida
Posts: 7,061
|
Quote:
OP, I think from what I have gathered this is normal with no lift shift. Not to many on here have used this function, heck, I don't think many even know their car has it... I think what happens is spark is cut for a millisecond so you don't over rev, but the injectors still keep firing, so that extra fuel gets dumped into the exhaust, hence giving you the backfire sound you describe. I called it a gunshot like sound, but I think the technical term is "afterfire". I'm sure someone with more knowledge on this will comment, but I think when you use no lift shift that loud backfire is 100% normal. |
|
01-16-2017, 05:01 PM | #6 |
マスタング = 遅い
Drives: 2017 Chevrolet Camaro SS 1LE Join Date: Aug 2015
Location: Florida
Posts: 7,061
|
Nope. It's active as long as you are going over 31 mph and have the throttle down more than 93% in any mode but snow/ice from what I can see. I think you need to be over 5000 rpm too. If you didn't get the loud "gunshot" like sound, you didn't do an actual no lift shift. As it has to dump the extra fuel when it cuts spark, which will ignite in the exhaust and give you that loud "backfire".
|
01-16-2017, 05:03 PM | #7 |
Drives: 2017 Camaro SS 1LE Join Date: Nov 2015
Location: Atlanta, GA
Posts: 148
|
So the no lift shift is basically normal shifting at WOT just without taking your foot off the gas correct?
__________________
Show: C7 Carbon ZL1 Front Splitter/C7 Carbon ZL1 Side Skirts/Diode Dynamics LED Sidemarkers/Tinted Headlights, Fog Lights, and Rear Reflectors/20" Forgestar F14's in Bronze Burst
Go: 17" Forgestar F14s in Bronze Burst with Hoosier Drag Radials/Rotofab Intake w/ Dry Filter/EFI Flex Fuel Kit/Kooks 2" Longtubes with Offroad Connections/PRAY Performance Ported Intake Manifold/PRAY Performance Ported Throttle Body/PRAY Performance Ported Heads/PRAY Performance Tune Suspension: Phastek Lowering Springs/BMR Toe Rods/BMR Control Arms/BMR Trailing Arms/BMR Strut Tower Brace |
01-16-2017, 05:05 PM | #8 |
マスタング = 遅い
Drives: 2017 Chevrolet Camaro SS 1LE Join Date: Aug 2015
Location: Florida
Posts: 7,061
|
Pretty much, but keep throttle floored, rip next gear...
Last edited by SS 1LE; 01-16-2017 at 06:12 PM. |
01-16-2017, 05:11 PM | #9 |
Drives: 2017 Camaro SS 1LE Join Date: Nov 2015
Location: Atlanta, GA
Posts: 148
|
And as it's something built into the ECU, how harmful is it to the trans and clutch? I do a good bit of racing so just seeing if it's worth using
__________________
Show: C7 Carbon ZL1 Front Splitter/C7 Carbon ZL1 Side Skirts/Diode Dynamics LED Sidemarkers/Tinted Headlights, Fog Lights, and Rear Reflectors/20" Forgestar F14's in Bronze Burst
Go: 17" Forgestar F14s in Bronze Burst with Hoosier Drag Radials/Rotofab Intake w/ Dry Filter/EFI Flex Fuel Kit/Kooks 2" Longtubes with Offroad Connections/PRAY Performance Ported Intake Manifold/PRAY Performance Ported Throttle Body/PRAY Performance Ported Heads/PRAY Performance Tune Suspension: Phastek Lowering Springs/BMR Toe Rods/BMR Control Arms/BMR Trailing Arms/BMR Strut Tower Brace |
01-16-2017, 05:51 PM | #10 | |
|
Quote:
__________________
2016 Camaro 2SS M6- Garage
|
|
01-16-2017, 05:55 PM | #11 |
マスタング = 遅い
Drives: 2017 Chevrolet Camaro SS 1LE Join Date: Aug 2015
Location: Florida
Posts: 7,061
|
No different to the clutch, and since it cuts a little spark shouldn't be too hard on the trans. I wouldn't do it every day, but if they put it there it can't be too bad. Heck, the old Cobalt SS even had no lift shift...
|
01-16-2017, 05:59 PM | #12 | |
Drives: 2021 LT1 10 speed auto Join Date: May 2013
Location: Connecticut
Posts: 2,343
|
Quote:
|
|
01-16-2017, 06:05 PM | #13 |
Drives: 2021 LT1 10 speed auto Join Date: May 2013
Location: Connecticut
Posts: 2,343
|
No, A NLS has be done exactly like a powershift, very quick bang next gear while just stabbing the clutch exactly the same time. If you push in the clutch before you pull/push the shifter into the next gear, the NLS feature shuts down if you are too slow.
|
01-16-2017, 06:06 PM | #14 |
Drives: 2SS & GT Premium Join Date: Jan 2017
Location: Southern Cali
Posts: 100
|
|
|
|
Post Reply
|
|
|