Hi, I have a lawn mower engine and I need to read and adjust its rpm precisely. I am totally lost. I would like to ask how some of you would approach this problem. What I have right now is I am going to buy an Arduino circuit board controller. Then I am going to attach a tachometer onto the engine. I really don't know how I am going to change the rpm but at least this will allow me to read the rpm and record it. Like I said I would GREATLY appreciate any suggestions!