it only measures the piezo electric signal the knock sensor sends out... the ability to read or hear knock is solely dependent on the ability of the sensor to pick up the engine vibration that is created during detonation...
[IMG]http://drivenauthority.com/kip/sigs/turbogagesig.jpg[/IMG] "..know your car better... RACE IT!.. AS OFTEN AS POSSIBLE.." This is a favorite.. "Drag racing is for fast cars... Autocross is for fast drivers.." but it's nice to do it all...