I'm not exactly sure what all I need to filter out, but I would like to start filtering out all data where acceleration is over a certain amount. To do this I need a custom calculated field, DeltaT = [time] - [time-1]. Why would megalog viewer tell me such a formula is "invalid syntax?" I am copying formulas from this website here, https://www.efianalytics.com/MegaLogVie ... mulas.html

Simple calculations:

deltaRPM=[RPM]-[RPM-1]

interpreted as:

deltaRPM = (Current RPM)-(RPM 1 record back)

If I could figure out why this is not working, I could then do some further math, deltaV = [velocity] - [velocity-1], DeltaV/DeltaT, then filter all values over 1in/s/s or something like that.

Here is a photo of some of my current unfiltered results. This is an upside down (rebound on top) plot of a miata bilstein, which appears to be a digressive valving with the knee somewhere around 1.5in/sec. It seems to me that most all of the garbage points are near the changeover points from compression to rebound, I am logging at about 30ms/33hz which doesn't appear to be fast enough to get a smooth transition. I guess I might need to look into better ADC converters, too.

And here is a picture of the "shock dyno" itself