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Your post doesn't surprise me. Porsche has an R&D budget in the hundreds of millions. If there were an easy fix to turbo lag, I expect that it would come from Porsche and not some company whose R&D budget is probably less than .00001% of Porsche's.
This is a 981 thread. There is no "turbo" or turbo lag in this discussion.
 

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Well mine arrived yesterday, and I just installed an tested it around the city. A about three weeks shipping from China, and the install was relatively easy other than the cramped working area down in the floor. The throttle is definitely more aggressive with this device!

However, stomping the throttle from a dead stop does still have the trademark Porsche PDK lag. With that being said, the OP is correct in that this device allows for throttle tip in at the slightest touch of the pedal which gets the car moving that little bit needed to avoid the lag when press further and in a hurry.

I need some more time with it to experiment, but I do think it will help as there aren't very many times where slamming the throttle to the floor from a stop is needed in normal day to day driving, however the need to pull out into traffic in a spirited fashion is needed, and this device seems to assist with that first few % of throttle needed to ramp up so you can then get her moving on with more confidence from that point.

Does it solve the dead stop lag issue......Nope. Does it help reduce the issue......I think it will with my limited experience so far, but time will tell better when I have some more real life driving experience with it
 

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Discussion Starter #23 (Edited)
From my limited experience with the car, it seems that in stock form the acceleration in first gear is very awkward, at least in my 2.7L PDK: there is initial tip-in hesitation, followed by lack of low-end torque to 3k, brief blip at 3k(?), perceived sluggish throttle response (I guess I defined this as throttle lag), and first gear is not completely smooth compared to the other gears (with or without the throttle controller), and not as smooth as the 2015 C4S PDK I test drove last year, if I recall correctly.

I have had some more time with the throttle controller since the installation in early August and here are my impressions now. The throttle controller really helps reduce the tip-in hesitation which is something that really annoyed me about the stock throttle as originally stated. I do feel much more confident accelerating from a dead stop whether in normal, sport, or sport plus, whether in auto or manual.

The throttle is indeed more responsive and much more to my liking. However, I feel that I sometimes need to be a bit careful because if I put my foot down fast or deep the engine wants to go as the throttle is much more sensitive now. It is not necessary to kickdown to the switch for the car to take off. I have had my unit set mostly at level P23 (and a bit at P24) during this time. I really like how the unit can be customized to the exact level of throttle response (makes me think of my R/C helicopter radios and setting throttle curves/EXPO!). Unfortunately, the throttle controller does not seem to help improve the sluggish acceleration between idle and 3k.

So far, I have had no problems with the unit and I am much more satisfied with tip-in and throttle response. I will never go back to the stock throttle and love my car even more now!

Questions for ICNU – just curious, how did you remove the throttle cable from the pedal assembly? This seems to be the biggest problem for those of us trying to remove the cable! Also, what settings have you tried so far with your GL500 and what do you prefer? I see you have the Cobb Stage II and added headers, do they also help with the tip-in and help to overcome the throttle lag in your CS? I had thought about Cobb but the price seemed prohibitive to me given my needs. Have you mounted your unit yet? If so, where? TIA.
 

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I largely solved any 'lag' in my 2014 and now 2014 both with PDK doing two things. I drive in Sport Mode and I have my seat position set for sitting close enough to the wheel that there is significant bend in my elbows and my seat is adjusted to the lowest point (closest to the floor). It means that the angle of my foot on the throttle is such that I move with more force than if I sat a bit further back and higher. Try it sometime...........you will be amazed at what a difference it makes in how different positions translate into differences in how much or little movement you have to make at the ankle to move the throttle. This, by the way, is my preferred position for driving (raced Go Karts for too many years I guess). I actually found this difference by accident, by the way. In my 2014, after picking it up from service, the seat position had been changed by the Tech and I had not noticed it immediately. Once I readjusted, I immediately became aware of 'more aggressive throttle response'.
 

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From my limited experience with the car, it seems that in stock form the acceleration in first gear is very awkward, at least in my 2.7L PDK: there is initial tip-in hesitation, followed by lack of low-end torque to 3k, brief blip at 3k(?), perceived sluggish throttle response (I guess I defined this as throttle lag), and first gear is not completely smooth compared to the other gears (with or without the throttle controller), and not as smooth as the 2015 C4S PDK I test drove last year, if I recall correctly.

I have had some more time with the throttle controller since the installation in early August and here are my impressions now. The throttle controller really helps reduce the tip-in hesitation which is something that really annoyed me about the stock throttle as originally stated. I do feel much more confident accelerating from a dead stop whether in normal, sport, or sport plus, whether in auto or manual.

The throttle is indeed more responsive and much more to my liking. However, I feel that I sometimes need to be a bit careful because if I put my foot down fast or deep the engine wants to go as the throttle is much more sensitive now. It is not necessary to kickdown to the switch for the car to take off. I have had my unit set mostly at level P23 (and a bit at P24) during this time. I really like how the unit can be customized to the exact level of throttle response (makes me think of my R/C helicopter radios and setting throttle curves/EXPO!). Unfortunately, the throttle controller does not seem to help improve the sluggish acceleration between idle and 3k.

So far, I have had no problems with the unit and I am much more satisfied with tip-in and throttle response. I will never go back to the stock throttle and love my car even more now!

Questions for ICNU – just curious, how did you remove the throttle cable from the pedal assembly? This seems to be the biggest problem for those of us trying to remove the cable! Also, what settings have you tried so far with your GL500 and what do you prefer? I see you have the Cobb Stage II and added headers, do they also help with the tip-in and help to overcome the throttle lag in your CS? I had thought about Cobb but the price seemed prohibitive to me given my needs. Have you mounted your unit yet? If so, where? TIA.
Your assessment of the PDK's first gear behavior is spot on, and being a RC heli guy myself, I fully get the expo reference!

The 3,500 rpm torque dip is very well known in these cars. About the only thing that solves that issue are headers which also add a good deal of low end torque as well where these cars are lacking, so double bonus!. This dip improvement can be clearly seen on all of the before/after header install dyno images that are posted in the various forums. The tunes alone cannot completely solve this torque dip without the headers as I already had both the Cobb and the TP Racing tunes. It felt like the TP racing tune made it a little less noticeable than the Cobb did, but not any huge improvement overall with either. I do not notice it anymore now that my headers were installed, and I have also since loaded the Cobb stage 2 tune up which they recently released for those running headers or IPD plenums and larger TB.

I can tell you conclusively that I instantly noticed the difference in performance with either tune installed vs stock and this was before my headers were ever installed! I removed the tune for about 2 months prior to the car going to the dealer for its annual checkup, and couldnt wait to get the tune back in, as it just didn't feel right to me anymore. Sort of like running in normal mode suddenly when all you normally drive in is Sport +

Getting the throttle cable disconnected from the pedal was harder than it needed to be for me only because I kept trying to press the little grey release button down with my fingers. It appeared to be fully depressed but nothing was coming loose. I finally gave up and use channel lock pliers which gave me that extra force needed to make it "click" all the way down and eject the harness. Its very simple to get loose once you understand what is needed to do it.

I have currently tested the booster in P2 - 2 and 3, and its pretty ferocious feeling with my headers and Cobb tune. I know there isnt more power being made, but the combo of bringing the throttle in so much more aggressively along with the torque increase from the headers and tune really make it feel that way! Like you, I realized quickly that you have to be very careful with the throttle or else the car can get moving a little too easily so Im looking forward to spending some time with it over the next week.

I cant even imagine the P3 "race" mode does. It must have the entire throttle range condensed down into only 20% of the pedal range. You would be at WOT with any pressure at all!
 

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I haven't had time to return the sprint booster and have been using it more in 'red' mode. I actually do think it makes the car seem faster because you press the throttle less to get to near or WOT, which is very doable in a 2.7 car in the lower to mid range (higher than 4k is usually okay too, but sometimes might cause you to lose traction). You need to shift manually, otherwise auto mode will kick you into 1nd or 2nd when you don't want. Shifting manually, you're basically doing WOT for a gear always instead of partial throttle naturally...which means you are going faster.

Pressing the throttle to near WOT mode actually does seem to elevate the dead stop hesitation lag (or it all happens much faster).

When you're using WOT in the car, you realize a bigger engine would mean you'd have to back on the power more (else it would be too rapid for normal driving...the 2.7 is snappy enough).

Red mode gives you the same instant forward jerk/response on the throttle as sport mode does normally and sport mode is even more rapid. Feels like the car is on overdrive along with headers/ cobb stage 2 tune with IPD/TB. I think this combo makes my 2.7 boxster much faster/ snappier than a stock one.

In summary, I'm not happy that the dead-stop WOT throttle lag is not resolved, the mod does seem to make the car 'seem' faster... I suppose you might get the same thing by heavier/ faster footwork though.
 

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You can't completely make up for the programmed lag of the throttle opening at lower revs by using a heavier and or faster right foot.

Because.....Whilst there is certainly merit in this as the revs rise, it really requires preemptive work on the throttle to mitigate the programmed delay in the opening speed at lower rpm. The sprint booster changes the speed at which the actual butterfly opens, so instead of a low rpm response to full throttle of around 1.5 seconds for the butterfly to fully swing open; in red mode, it's instant. If you have the urge or need to just plant the accelerator it opens. In red mode, instantly, not gradually over 1.5 seconds (or thereabouts) even though your right foot is buried into the floor. That is the real impact, after that, yes you certainly just use a heavier of faster foot, but you can't change that low end butterfly lag without some sort of device similar to this.

Of course the remapping also means less throttle for more rpm. On the BMW forum a person posts static throttle position in "off", "sport" and "race" (red) mode in neutral, and the revs jump from 2,000, to 4,000 to well over 5,000 as he switches modes. That makes its own impact on how things feel.

Just my research, having bought one.

Cheers
 

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SprintBooster is the only mod I have left on my car. While it doesn't fix the lag, it does make a perceived change in making th car faster. With very little pedal travel, you can open the throttle to 100% instead of like 80% unless you are in the habit of always flooring it. This works well with manually shifting PDK...you are able to extract all the limited power at lower revs. I keep mine at red setting always unless PDK is placed in auto mod (red setting would cause it to downshift too easily).
 

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Hi Minthral,

Does that mean you also removed the ECU tune? Those are pretty handy. If so, why?

Cheers Les


Sent from my iPhone using Tapatalk
 

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Anyone been running one of these GL500 devices for 2-3 years now? Curious to know about long-term reliability. It's somewhat terrifying to contemplate what would happen if the device gets fried or malfunctions while driving... though perhaps worse case would be that there isn't any throttle response at all.
 

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Anyone been running one of these GL500 devices for 2-3 years now? Curious to know about long-term reliability. It's somewhat terrifying to contemplate what would happen if the device gets fried or malfunctions while driving... though perhaps worse case would be that there isn't any throttle response at all.
Mine has been in since the Summer of 2016 with no problems
 

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Discussion Starter #32
Anyone been running one of these GL500 devices for 2-3 years now? Curious to know about long-term reliability. It's somewhat terrifying to contemplate what would happen if the device gets fried or malfunctions while driving... though perhaps worse case would be that there isn't any throttle response at all.
I have also been using the unit since the summer of 2016, about 13,000 km to date. (Mine is set to P33). Still working great (knock wood) and I love it!
 

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So, I've had the GL500 installed on my 718 Cayman GTS for about six months now. After trying the various modes, I've settled on P1.7, as P2.x and P3.x produce a very unnatural (and unsafe) acceleration curve. That said, a perfect balance is impossible, apparently. I find it works great in traffic for rapid lane changes (e.g. when you're stuck behind an unexpected left-turner and no one will let you change into the adjacent lane -- the lag is very obviously reduced from 1.5 seconds to about a half-second). However, when the car is already moving at a decent clip, it's not terribly useful. I usually disable it on spirited mountain drives and track days.

There's one situation that is outright terrible, though. If you depress the gas pedal, say, 70%+ from a dead stop, the PDK transmission sometimes MISSES the gear change to second and you violently lurch back and forth, stuck in 1st gear unless you react quickly and hit the paddle upshifter. What I suspect is that the PDK expects you to smoothly (albeit near instantly) depress the pedal from 0 to 100%, but the throttle controller outright skips reporting a critical part of that range completely, leaving you in a state the ECU doesn't expect. There should definitely be some kind of fail safe built into the PDK to avoid this situation, regardless of the cause, IMO. But, anyway, if you know you're going to floor it, definitely switch the unit to Normal (bypass) mode or else keep the car in manual mode (paddle-shifting only).
 

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Reviving an old thread as I have just tried to install the same unit (a different name, but looks identical)

But... it doesn't work. It lit up and showed the drive mode, but gave me a 'reduced engine power' warning light and moving the accelerator did nothing at all, it's like the accelerator wasn't connected to the car. I tried switching between the stock setup without this installed, and installing it again a few times but nothing changed. I'm in a 2010 987 2.9. Any ideas?
 

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recently bought my first Porsche, a 981S .i thought it was faulty as when running in Pdk normal the acceleration after freewheeling/off throttle was terrible like mentioned above.1 to 2 sec delay before you got forward motion but thats apparently due to the stop/start and economy setting which disengage the drive line for coast mode.Gets their mileage figures right up and i actually use it for normal driving but when driving on in a b road setting with braking/downshifts/corners etc i always use sport or sport plus as it disengages the coast feature.you can also switch it off using the stop/start disable button.

Is this the issue thats being discussed here or something completely different....
 

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It is annoying when you want to get up and go. Some says that you just have to push pedal further but it is actually a different Nox Vidmate VLC feeling when its sensitivity is significantly increased to boost reaction time and should also add driving confidence when the moment is called for.
 
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