I have a G Tech meter that some how has a tach built into it. I still have not figured out how this thing gets an RPM reading by being plugged into the lighter port, but anyway....it can log the RPM during a 1/4 mile run and stock my car would make the 1st-2nd shift around 5800 RPM and with the LET tune it shifts at around 6300 according to the data it stores.