No lift shift in MT 991.2 GT3
03-22-2018, 08:09 AM
#106
I feel vindicated. 😊
03-22-2018, 08:46 AM
#107
Let me explain why I thought this would work and why I'm not surprised that it does.
Porsche has had rev-matching since, I believe, 2014. Maybe 2015. This works when you're off the throttle and, when to put the stick in some gear, the computer controls the throttle to put the revs where they need to be for that gear.
You can mess with the computer by picking different gears. It'll rev-match to whichever one you pick.
Now, this "no-lift" shifting is new, but the only way I imagine it working is that it takes over the throttle when you put the clutch in. It seems to me that it's exactly the same as the rev-matching feature except that it overrides the throttle when the pedal is down rather than just controlling it when you're not.
When it detects the clutch in, it takes over. It doesn't know what gear you're about to choose. Once you pick one, it sets the revs appropriately and when you let the clutch out it gives you back control of the throttle and goes to WOT since you've got the pedal down.
With that being the case, it shouldn't matter whether you're shifting up or down. It should set the revs appropriately, making the no-lift downshift to accelerate a perfectly reasonable thing for it to do.
It seems like a neat gimmick that's easy to implement given that they already had rev-matching figured out. I don't really see the value though since this one REALLY requires a change in how you drive and it's a change that would create a BAD habit if you ever get into another car that doesn't do it. For my part, I think I'll just carry on shifting like I always have and just use the rev-matching for when I'm trying to go faster and my heel-toe game isn't quite on point.
Porsche has had rev-matching since, I believe, 2014. Maybe 2015. This works when you're off the throttle and, when to put the stick in some gear, the computer controls the throttle to put the revs where they need to be for that gear.
You can mess with the computer by picking different gears. It'll rev-match to whichever one you pick.
Now, this "no-lift" shifting is new, but the only way I imagine it working is that it takes over the throttle when you put the clutch in. It seems to me that it's exactly the same as the rev-matching feature except that it overrides the throttle when the pedal is down rather than just controlling it when you're not.
When it detects the clutch in, it takes over. It doesn't know what gear you're about to choose. Once you pick one, it sets the revs appropriately and when you let the clutch out it gives you back control of the throttle and goes to WOT since you've got the pedal down.
With that being the case, it shouldn't matter whether you're shifting up or down. It should set the revs appropriately, making the no-lift downshift to accelerate a perfectly reasonable thing for it to do.
It seems like a neat gimmick that's easy to implement given that they already had rev-matching figured out. I don't really see the value though since this one REALLY requires a change in how you drive and it's a change that would create a BAD habit if you ever get into another car that doesn't do it. For my part, I think I'll just carry on shifting like I always have and just use the rev-matching for when I'm trying to go faster and my heel-toe game isn't quite on point.
03-22-2018, 10:33 AM
#108
Addict
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I don't really see the value though since this one REALLY requires a change in how you drive and it's a change that would create a BAD habit if you ever get into another car that doesn't do it. For my part, I think I'll just carry on shifting like I always have and just use the rev-matching for when I'm trying to go faster and my heel-toe game isn't quite on point.
Probably best to drive the car fully manually if this is an issue.
03-22-2018, 10:47 AM
#109
This is true of upshifting as well as downshifting - if you have another car without the automated feature (as I do with my 73 911), you can potentially develop muscle memory that could cause a problem in the other car...
Probably best to drive the car fully manually if this is an issue.
Probably best to drive the car fully manually if this is an issue.
The difference with the rev-matching though is that you're not doing something you should be doing. It's not really a problem. Just a "DOH!" moment when you realize that a thing you wanted to happen hasn't happened. With this no-lift shifting you're actually DOING something you otherwise shouldn't be and counting on the car to make it right. I guess the worst that will happen is that you pin the tach at the rev limiter... but still... that doesn't seem ideal.
03-22-2018, 01:10 PM
#110
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There's been more than one out lap at Mosport where I dive into turn 5a and grab 2nd gear only to discover I forgot to hit the Sport Plus button and completely botch the shift.
The difference with the rev-matching though is that you're not doing something you should be doing. It's not really a problem. Just a "DOH!" moment when you realize that a thing you wanted to happen hasn't happened.
The difference with the rev-matching though is that you're not doing something you should be doing. It's not really a problem. Just a "DOH!" moment when you realize that a thing you wanted to happen hasn't happened.
I watched a buddy spin his E36 BMW M3 many times into a slow corner, before I explained to him the necessity to match revs on downshifts. Was his first track outing.
03-22-2018, 01:31 PM
#111
Well, if you're not using the Rev-Match (because you forgot to press Sport or driving a car without the feature) and don't do it yourself going into a corner, this can cause a spin (so some risk of a real problem, aside from just the additional wear on the car if done repeatedly). Less likely to happen if the car in question has ESC and it's active.
I watched a buddy spin his E36 BMW M3 many times into a slow corner, before I explained to him the necessity to match revs on downshifts. Was his first track outing.
I watched a buddy spin his E36 BMW M3 many times into a slow corner, before I explained to him the necessity to match revs on downshifts. Was his first track outing.
04-23-2018, 12:04 PM
#112
7th Gear
Power delay
Thanks for the posts about not lifting the throttle when upshifting. I was wondering why there was a power delay when I upshift in the “normal” fashion at higher rpms. Kinda like a turbo lag. What I think is happening is I am cutting the gas (with the gas pedal) and the computer is also cutting the gas (with the clutch pedal). This redundancy is causing a slight delay to the power coming back on when the throttle is re-opened. Only happens at higher rpm shifts. No-lift unshifting should fix this.
04-23-2018, 07:56 PM
#113
This is what happens when you don't use no-lift shift.
You go pick up your 93 year old grandmother in milan for lunch during European Delivery. Of course being the badass that she is (she personally bitch-slapped mussolini while he was hanging upside down let's not forget ) she asks to sample launch control. Having completed 1700km of careful break-in procedure, I feel comfortable honoring my grandmothers request to pop the gt3's cherry. It's raining hard outside so I chicken out a bit and don't quite flat-shift. As you can tell from the video she's deeply disappointed and says "no no no no no... stop stop stop enough".. she then proceeds to call her grandson a complete pu$$y for not holding my foot down completely. Lesson learned, lesson learned!!!! Sorry grandma... we'll go faster next time.
https://youtu.be/eV0nOGQd0HY
You go pick up your 93 year old grandmother in milan for lunch during European Delivery. Of course being the badass that she is (she personally bitch-slapped mussolini while he was hanging upside down let's not forget ) she asks to sample launch control. Having completed 1700km of careful break-in procedure, I feel comfortable honoring my grandmothers request to pop the gt3's cherry. It's raining hard outside so I chicken out a bit and don't quite flat-shift. As you can tell from the video she's deeply disappointed and says "no no no no no... stop stop stop enough".. she then proceeds to call her grandson a complete pu$$y for not holding my foot down completely. Lesson learned, lesson learned!!!! Sorry grandma... we'll go faster next time.
https://youtu.be/eV0nOGQd0HY
A lot like this video of Riccardo Patrese not going fast enough for his wife...
04-23-2018, 08:28 PM
#115
Rennlist Member
04-23-2018, 08:44 PM
#116
Race Director
Originally Posted by Jimmy-D
I have tried no lift shifts on numerous occasions and it just messes with me big time.
It just feels so awkward and tough for me to mentally adjust
It just feels so awkward and tough for me to mentally adjust
05-26-2019, 10:20 AM
#118
06-06-2019, 01:21 PM
#119
Instructor
If Sport button is not selected, electronics will not interfere with your shifting either up or down. With Sport button selected, rev matching is active on down shifts and some weird feeling on up shifts to land the RPM just right with engine speed for smoother feeling. I personally dont like Sport button on track. I only use it in traffic when I’m driving slowly and heel and toe action is just too aggressive for slow street driving (i noticed when you blip the throttle on down shifts, it also overrides Sport commands if its active).
06-06-2019, 01:29 PM
#120
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When I started this thread I didn't own a 991.2 gt3. I had a gt4. In the gt4 I always used the rev match. I had some difficulty getting it just right on the street and on track it's a no brainer for me. One less thing to do and I can focus on my line and braking. HOWEVER on my GT3 I never use it on the street. For some reason I feel it's much easier to rev match in this car. Maybe it has to do with the wider engine rev range (I have zero clue) but I can do it perfectly and smoothly every time. And it sounds better lol. So on the street it's no aids. On the track or smokies mountain runs it's on though. Keeping up with Ryan R and Andy P is hard enough lol