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Originally Posted by vtirocz
Al,
My primary reason for asking this question is to confirm that the No-Lift Shift (NLS) algorithm is functioning properly on my 2017 1SS. At this year's Camaro Fest in Bowling Green, I asked during the Q&A about the NLS algorithm and you confirmed it was enabled on all 6th gen manual transmission Camaro SS cars. I recently tested the feature out and it did not work how I was expecting. Before I use it again, I'd like to confirm I'm executing it correctly and not just banging into a 6500 RPM limiter if that's not how the feature is supposed to work. Could you please help me clear up the following questions:
1. When the accelerator pedal is at 100% and remains there throughout the procedure, what should engine speed do as the clutch pedal gets depressed and the shift lever moved to the next gear? Does engine speed jump to and get held at 6500 RPM or is engine speed supposed to reduce?
2. What are the enable criteria for the no-lift shift algorithm?
3. Is the algorithm tuned exactly the same between the SS 1LE and SS without 1LE package?
Background information and follow-up questions:
When I perform a no-lift upshift, as I depress the clutch the engine speed will go to 6500 RPM and stay there.... I'm concerned that the feature is not working as intended and it might just be hitting a normal rev limiter....Does PTM in the 1SS 1LE impact the NLS algorithm?
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AL's ANSWER:
First of all,
I’m glad you Camaro owners are using all of the functions of the car, including No-lift Shifting. Our engineering team is always looking for the best ways to combine performance and technology to improve the Camaro driving experience. This new “ask Al” forum seems like the perfect place to go further into detail on some of the features that may not get the proper explanation in the Press Releases or media outlets. I’d like to explain what the feature is, first, then explain how to use it on your Camaro. The Camaro has actually had ‘No-lift Shift’ since the 5th Generation. It is a feature that is intended for our drivers who want the performance feel of quick power shifting in our manual transmissions. The feature keeps the throttle at full open for both our boosted and non-boosted applications when passing through the Engine Over-speed Protection during a shift. In Engineering terms, when triggered, there is an immediate torque control, with fuel and spark, for a given period of time. Then, a predictive control takes over using the throttle to control torque. This allows the driver to take advantage of fast torque control for a short period of time (e.g. during the shift) without heating up or damaging the catalyst over time.
To address the most common question about the feature, you should know that there are both enable RPM’s and target RPM’s for each transmission, which are different for each engine application on the Camaro. We’ve put together a table below to show enable and target RPM by engine. To perform a No-lift Shift, simply put the throttle to the floor (i.e. WOT), and keep it there. Once the tachometer reaches the enable RPM, you can depress the clutch and shift as quickly as you can, and you’ll notice the tach will go to your target RPM during the shift. For example, if you are driving a 2017 SS Manual, with your throttle pedal to the floor, and the tach above 5000 RPM, say 5100 RPM, you can quickly upshift without lifting your throttle foot. The tach will reach the target RPM, in this example 6400 RPM, but not flare to redline. You can quick shift at any time during this RPM range. By the way, in our 2.0T Camaro (RPO LTG), if you are performing a No-lift Shift sequence, you will notice that you don’t lose boost during shifting, as you would with normal shifting. This adds up to an improved lap time or quarter mile. Also, you need to have a minimum speed of 15 kph (9.3 mph).
I would like to address a few of the specific comments with regard to No-lift Shifting. As I mentioned, the feature is on all 6th Generation Camaro Manual Transmissions, with the exception of the 2016 2.0T and V6. Those were added in Model Year 2017 and beyond. With regard to the effect of Mode selection on No-lift Shift, there is no difference between Tour/Sport/Track/Snow-Ice mode or PTM mode on the ability to perform the quick shifts. Most people either don’t keep the throttle to the floor, or don’t wait until they reach their Enable RPM before performing their shift. Both are required criteria to execute the No-lift shift feature. Lastly, the Enable and Target RPM is different for each engine application, and even within an application (as in the SS and SS 1LE).
If you are having problems using the feature, give it a try as I’ve described in this response. It may seem counterintuitive to keep your throttle to the floor while shifting, and the V6 and SS target RPM’s seem close to redline, but trust that it works. It may just take some practice.
Good luck with our No-lift shifting! I hope this response is helpful, and the type of information you were looking to see from the Camaro team.
Until next time,
Al O.