Reading wrong RPM with VR

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roboluke
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Joined: Thu Nov 03, 2016 5:59 pm

Reading wrong RPM with VR

Post by roboluke »

Hi,

So I have a BMW M30 with single coil ignition and a VR sensor reading a 60-2 trigger wheel. But when I crank the motor (fuel pump turned off) the RPM reads at about 3800-4000 RPM. I believe I have the correct settings as I compared to other people's settings with the same setup. Any idea on what this could be?

Thank you!
trakkies
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Joined: Tue Dec 30, 2008 3:06 am
Location: SW London, UK

Re: Reading wrong RPM with VR

Post by trakkies »

It this cranking RPM as read in Tuner Studio? If so, post your MSQ file here.
Dave P, London UK.
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roboluke
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Re: Reading wrong RPM with VR

Post by roboluke »

Is it something with 'skip teeth' for tach? How do I calculate what that value should be for a 60-2 wheel? Is it 60 because 60 is one full revolution?
ms2tuning
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Re: Reading wrong RPM with VR

Post by ms2tuning »

As previously asked .... is this the rpm you are seeing in tuner studio ... or is it on the rev counter in the car?

The 60 -2 wheel is just set up as a trigger wheel ... then set 60 teeth and 2 missing teeth. If tuner studio is reading 4000 ... there is something wrong with either the trigger wheel settings ... or the board has not been set up for a VR input and is getting confused. or if the rpm is jumping around all over the place ... then it is likely that the sensor is not correctly aligned with the trigger wheel.
Matt Cramer
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Re: Reading wrong RPM with VR

Post by Matt Cramer »

Can you post your MSQ?
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