Gearbox and re-gear
07-10-2020, 10:04 PM
#16
I can imagine adaptive implementation but I doubt Porsche would implement that in anticipation of gear ratio change.
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ForeverCar (07-10-2020)
07-10-2020, 10:59 PM
#18
It will be a bit more problematic for those that increased the 5th to 6th split. This way, if auto blip target doesn’t change from stock, 6th to 5th down shift will blip to rpm that is not high enough. Timing won’t help here but synchro/clutch slip can deal with it.
Not making judgments here as I just want to find accurate information.
07-11-2020, 03:42 AM
#19
Three Wheelin'
When I checked last time, they had modified 2 - 4 or something like that. But, those ratios are designed for 4.0 conversion, not for stock 3.8. So, the Vmax for 3.8 may not be optimal. Also, even for 4.0, the Vmax are not that much lower from stock. At least, not low-enough for me. So, still won't meet my requirements. I need to talk to them to see what they can do. I was all set to change the Final Drive ratio this summer for the 981; then, the Covid thing put a break on my conversion road trip! All I care is low 1 - 3!
08-04-2020, 12:17 PM
#20
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DeMan has a solution for the mainshaft gears.
Autoblip apparently works perfectly on the modified gearing cars.
@DeMan Motorsport can verify I am sure.
Autoblip apparently works perfectly on the modified gearing cars.
@DeMan Motorsport can verify I am sure.
Don't ask how the factory engineers made the math for this to work out, nobody knows..
But I can tell you after many installations its been perfect every time.
__________________
2016 GT4-R
Rick DeMan
DeMan Motorsport
Upper Nyack, NY
845 727 3070
Porsche Sales & Service
Porsche Race services and parts
www.DeManMotorsport.com
2016 GT4-R
Rick DeMan
DeMan Motorsport
Upper Nyack, NY
845 727 3070
Porsche Sales & Service
Porsche Race services and parts
www.DeManMotorsport.com
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SFZ GT3 (08-07-2020)
08-04-2020, 04:05 PM
#21
Yes, the short 2-5 gears work PERFECTLY without any issues whatsoever with the Auto Blip. Perfectly, not a single issue, no problems, how many ways can I say it? Works as delivered from the factory!!
Don't ask how the factory engineers made the math for this to work out, nobody knows..
But I can tell you after many installations its been perfect every time.
Don't ask how the factory engineers made the math for this to work out, nobody knows..
But I can tell you after many installations its been perfect every time.
With your fantastic reputation, I'm happy to take your word for it without the need to understand how it is implemented.
After putting 800+ miles one the car, I find the stock ratios to work quite well for how I used the car. Of course, it doesn’t mean I won’t get bored and want to change it just for the different experience.
08-05-2020, 12:30 AM
#22
One cheaper solution is just to opt for a PDK like I did. 
08-05-2020, 06:47 PM
#23
08-05-2020, 06:48 PM
#24
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08-05-2020, 06:57 PM
#25
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08-05-2020, 06:58 PM
#26
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We know nothing about the PDK in the GT4/Spyder. We don’t know what kind of PDK it is (regular or PDK-S), we don’t know the gear ratios, we don’t know what it weighs, and we don’t know anything about its performance. Outside the USA, PDK availability has not even been announced for the GT4/Spyder.
08-05-2020, 07:05 PM
#27
Addict
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In this case, they electronically juiced the torque curve a bit for PDK (so delta could be wider than usual).
08-06-2020, 06:03 PM
#28
Rennlist Member
interesting - I guess we will have to wait and see!!! 0.4secs seems like a small delta, about the difference between a PDK shift and a *very* fast manual shift ... if in fact a shift occurred?
08-07-2020, 10:15 AM
#29
RL Community Team
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As you already know, you will lose the powertrain warranty if the transmission is modified. The issue "tall gearing" seems to mean different things to different people. To me, tall gearing means the speed is much higher to be able to shift at or just past the peak power RPM. I want lower Vmax in gears 1-3. Gears 1 and 2 are on the mainshaft. So, will need to change the mainshaft as well. Changing the Final Drive ratio cuts the Vmax across the board. However, the Pinion will have accelerated wear, as compared to stock, even for spirited street driving. Ideally, mainshaft+first-3 gears would be preferred. If DeMan or GT Gears don't make them, then Final Drive ratio from AutoQuest. I plan to talk to these companies at some point. The stock gearing will simply NOT work for me! But, I might wait until powertrain warranty runs out!
Have to agree, so far it has been a non-issue...
08-10-2020, 12:50 AM
#30
It was an issue on the 981 GT4 and my 981 Spyder. I see no issue on my 718 GT4. Multiple Owners of the 981 GT4 Have driven y 718 GT4 and agree that in the new model you just power through Second into 3rd then 4th. Totally dfferent from 981
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Croc999 (08-10-2020)