I would be interested in seeing your arithmetic. As they used to tell us in engineering school "no credit if you don't show your work".
In the spirit of fair play, I'll show my work first:
The energy stored in an ignition coil is the 1/2 the inductance in henries times the square of the steady-state current in amps. (E = 1/2LI2)
The inductance of a typical automotive ignition coil is 9 millihenries, although for our discussion the actual inductance is irrelevant since you didn't swap the coil. (The inductance "comes out in the wash".)
Coil energy with original resistor: E = 1/2LI2 E = 1/2L(V / R )2 E = .5 * .008 * (12 / (2.2 + 1.8) 2 E = .004 * (12 / 4)2 E = .004 * 32 E = 36 millijoules
Coil energy with new resistor: E = 1/2LI2 E = 1/2L(V / R )2 E = .5 * .008 * (12 / (1.8 + 1.8) 2 E = .004 * (12 / 3.6)2 E = .004 * 3.32 E = 44 millijoules
So your resistor swap gained you a whopping 22 percent increase in spark energy.
Questions: 1. How is it that an engine in good running condition can go from not running to running perfectly just with a 22 percent increase in coil energy? 2. Are you confident you can accurately measure resistance to an accuracy of less than half an ohm? I did this for a living for many years, and I know I can't do it unless I have a multimeter capable of performing a four-wire resistance measurement. (I'm pretty sure your meter doesn't do four-wire.) 3. Did you bother measuring the point resistance, and if so, what was it? Half an ohm resistance across the points will obliterate increased current you gained from your resistor swap.
Look forward to reading your answers and seeing your math.
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Today's Featured Article - Hydraulics - Cylinder Anatomy - by Curtis von Fange. Let’s make one more addition to our series on hydraulics. I’ve noticed a few questions in the comment section that could pertain to hydraulic cylinders so I thought we could take a short look at this real workhorse of the circuit. Cylinders are the reason for the hydraulic circuit. They take the fluid power delivered from the pump and magically change it into mechanical power. There are many types of cylinders that one might run across on a farm scenario. Each one could take a chapter in
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