Gear position incorrect

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Gear position incorrect

Post by tonytkdk » Wed Jun 26, 2019 1:30 am

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


The configuration of the vehicle. 2015 Porsche 981 Cayman GTS PDK

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.


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Re: Gear position incorrect

Post by Harry » Wed Jun 26, 2019 1:15 pm

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".

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Re: Gear position incorrect

Post by ereynold60 » Wed Jul 03, 2019 3:50 pm

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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