Gear position incorrect

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tonytkdk
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Gear position incorrect

Post by tonytkdk »

* [pros1] May I know what could be the problem of incorrect gear position display?

[youtube]https://youtu.be/jaB6eFsXZrQ[/youtube]

The configuration of the vehicle. 2015 Porsche 981 Cayman GTS PDK
https://imgur.com/a/2cyvGZL

Is the circumference a matter? I checked the 245/35R20 and 265/35R20 Cup2 N0's online document to fill the value.
Is there a bug of gear display so far?

* [pros2] The rev seems not that smooth sometimes. Here's my OBD2 sensor info.


Image
https://imgur.com/a/bcpAgij

Hugo
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Harry
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Re: Gear position incorrect

Post by Harry »

We have a FAQ on this available in viewtopic.php?f=39&t=3425. The calculation in LapTimer can be considered bug-free. In case you are facing issues either the parameters entered are wrong / incomplete, or RPM / speed data delivered by OBD are inconsistent. For the later, we have another FAQ available named "Debugging OBD connections".

- Harry
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ereynold60
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Re: Gear position incorrect

Post by ereynold60 »

I had a similar problem with incorrect gear being displayed until I corrected the "final drive ratio" to account for the "constant ratio" ( I can't recall where I found this). Here are the settings I use for my 2014 Cayman S with PDK (should be same for your 2015 GTS):


Drive Ratio = 3.62 --NOTE: 3.25 Final Drive Ratio X 1.114 Constant Ratio = 3.62
Num of Gears 7
Gear 1 Ratio = 3.91
Gear 2 Ratio = 2.29
Gear 3 Ratio = 1.65
Gear 4 Ratio = 1.30
Gear 5 Ratio = 1.08
Gear 6 Ratio = 0.88
Gear 7 Ratio = 0.62
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