Review on 🚗 Electronic Specialties EZ-Tach 325: The Ultimate Digital Automotive Tachometer for Precision Measurement by Rance Riley

I think it worked great. Please note this is for cars but so many bad reviews complain it doesn't work on small engines. It was easy to connect to my spark plug wire and once connected it started reading right away. The reading was not stable at one RPM setting and bounced up and down +/- 50 RPM, but I don't think this is a problem with the tool. I don't think my car or any other car really drives at constant speed. all the time and the displayed vibration was not displayed on the lap tachometer, which is why some may think that the engine is stable if this display does not work. Most importantly, it helped me get the idle on the right setting and it helped.