Thread: Getting 1/4 mile times

OBD-II updates are not fast enough to be able to peg down quarter mile times like this. There are some experiments using OBD-II for quarter mile timing and even in-car dyno, but the accuracy is crap. you can get better ideas measuring out a quarter mile and driving with a stopwatch.

If you want a better in car measurement, the Passport G-Timer I hear is pretty good, though I dont use it and don't know anyone who does.

If you want to check out the OBD-II stuff for it, look at OpenDiag the linux OBD-II stuff on sourceforge.net.. The CVS version has the dyno mode. I could not get it to work in my car, though, so YMMV.

The best option for this would be to get an accelerometer sensor and hook that up to your carpc. If you get an accurate one and calibrate it properly, you should be able to get very good readings off of this. I might do this at some point to track my runs through an autocross track. I would interpolate GPS data with accelerometer data to derive position readings every 1/50 second or so.. would also work for straight line measurements. AFAIK, the G-Timer is calculating velocity and distance with an accelerometer as well.

the digimoto obdii comes with a program that does 1/8...1/4.. and dyno.


probably not 100% accurate but its 100% cool.


lol