RPM slow response to app

General Q&A specific to RaceCapture/Pro. For app related questions post in the RaceCapture App forum. also see the <a href="http://www.autosportlabs.net/RaceCapture">RaceCapture Information Page</a>

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PS14
Posts: 97
Joined: Fri Feb 12, 2016 11:27 pm
Location: NY

RPM slow response to app

Post by PS14 »

Watching some in car footage i noticed the RPM guage seems to show the same readings alot. like "5445". its not smooth or updateing fast enuff? any thoughts on what would cause this.

Here's a link to a 30 sec video where you can see what i mean. https://youtu.be/LSXodl13IYc

MK2/Rpi on latest app and firmware.
USB cable from MK2 to Rpi dash
Rpm channel set to medium and 25htz (same as all other channels) pulled in from a CoilX attached to kettering type ignition (GM Hei)

Thanks, Dave

brentp
Site Admin
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Joined: Wed Jan 24, 2007 6:36 am

Post by brentp »

Hi, is this your car's video, or something you found online?

Best would be to do a controlled test to carefully observe the RPM response. There's too little information in the video you shared for us to comment. Overall, RaceCapture calculates RPM on every ignition pulse, which will make it very high resolution.
Brent Picasso
CEO and Founder, Autosport Labs
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PS14
Posts: 97
Joined: Fri Feb 12, 2016 11:27 pm
Location: NY

Post by PS14 »

its my gopro footage. at first i thought maybe it was a video issue. it just seems odd that i see the same rpm readings repeating. it will do the same thing sitting in the shop and reving the engine, as tho the display cant update fast enuff.

brentp
Site Admin
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Joined: Wed Jan 24, 2007 6:36 am

Post by brentp »

Yes, a test in your shop in a controlled environment would be helpful.

Try varying RPM at different speeds and see if the RPM updates smoothly on the display.
Brent Picasso
CEO and Founder, Autosport Labs
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mdknutsen
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Joined: Mon Feb 04, 2019 12:17 am

Post by mdknutsen »

Any update on this? Ive been having s similar issue.

brentp
Site Admin
Posts: 5956
Joined: Wed Jan 24, 2007 6:36 am

Post by brentp »

Hi mdknutsen,

How are you reading your RPM? Direct wire, CAN bus mapping or OBDII? If OBDII, what year is the ECU?
Brent Picasso
CEO and Founder, Autosport Labs
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