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Old 05-07-2008, 10:37 PM   #4 (permalink)
Dan.
MPG Centurion
 
Join Date: Apr 2008
Location: Houston, TX
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Quote:
Originally Posted by larrydag View Post
One thing comes to mind. Is it practical for instantaneous FE or is it just for data logging?
Yep, this should give MPG (or one should be able to re-write it too). I'm not sure the exact math to derive MPG from the OBD primitives, but something like (MPH/RPM)*X should do it. 'X' would be derived in part from your displacement. That's a real super dumbed down way to get MPG but it's better than nothing. I know the commercial gauges key off of speed an manifold pressure (for what it's worth).

EDIT:
[QUOTE=dcb;24089]Note that you can do the mpg part with just a laptop/carPC/tablet (with a sound card), running almost any operating system on any fuel injected car: http://planetchampions.org/diympggauge/Too cool. I know Prius guys used to tap a line with a curcuit so they could "listen" to the High Volt system. They could tell regen, assist and other things to a degree you couldn't see on the dash. Piped it out through the system speakers. All signal processing was done with the Cranium™ Hu OS (ears ).

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Best commute = 14.3mi @ 114 MPG (sg2)
Best (non-trivial) tank = 759mi @ 80.7 MPG (fcd)
MPG Centurion-Hybridfest 2007-Prius II-26mi @ 106 MPG (sg2)
Dan <11011011>

Last edited by Dan.; 05-08-2008 at 10:56 AM..
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