I was told thete would be no math! I'm thinking if I have one coil per cylinder and test off of just one coil, I treat the reading as a 1 cylinder? 4 cylinder scale and divide by 4? That puts my idle speed at 4K or so.. my little test meter don't go that high.. I may be tool shopping..
There is no math. Just hook to one coil and it only fires once per revolution. You only need to divide if the coil fires more than once per revolution.
On single coil systems you need to divide by the number of cylinders it fires for. With each cylinder getting its own coil, no division required.
If you are using a tach with multiple cylinder selection only, then divide by the number of cylinders you have selected.
