OBD Speed is about 10% lower than Actual

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Searya
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OBD Speed is about 10% lower than Actual

Post by Searya » Mon Oct 19, 2020 5:49 pm

I used an kiwi3 obd adaptor to capture RPM this past weekend. While attached I believe the app also started using OBD speed which was showing 100mph while GPS (using the force overlay option) was showing 112mph.

I found a setting in admin\settings\expert settings\obd tweaks called 'Speed Multiplier'. I changed the setting from 1 to 1.1 but it had no impact.

Any ideas on how to get the obd speed readings working correctly?
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Harry
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Re: OBD Speed is about 10% lower than Actual

Post by Harry » Mon Oct 19, 2020 6:57 pm

The speed multiplier is applied during recording. It doesn't change existing recordings.
Please make sure you drive on a straight at constant speed when reading the values you want to map. A highway drive is perfect. Once you have OBD and GPS speeds, set the speed multiplier like this:

new speed multiplier = GPS speed / OBD speed * old speed multiplier
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Searya
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Re: OBD Speed is about 10% lower than Actual

Post by Searya » Mon Oct 19, 2020 7:25 pm

Thanks that is great. I have it set for my next event!
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