Re: Ignition coil
OK... I have done my best here. Please consider that electronics engineering is not my educational background. Feel free to critique my comments, as I am always open to learn. (A core reason for what little successes I have had in my lifetime)<br /><br />Keep in mind that an engine is a system of systems, each operating in their own area of expertise (fuel/air/ignition/electrical/etc...), towards a common function. (Keep the engine running)<br /><br />The ignition system is designed to operate at utmost efficiency for the engine it was designed for. In other words, on a 1977 250 Mercruiser the points, condenser, coil, plug wires, plugs, etc, was all designed to be compatible to run that particular engine, at the designed speeds and workloads intended by Mercruiser. This means that the coil was designed to fire the suggested spark plugs effectively at all of the engine's designed parameters. A car or truck would have different design parameters, based on it's intended use.<br /><br />The design factors of the coils are not limited to the coil itself. The coil's design may change based on the type of plugs in the engine. It might also change based on the actual primary voltage in the ignition system. Typically, we associate 12 volts to be the primary voltage. However, we all know that battery voltage varies with charging system output. Now does the resistor need to drop 3 volts? or 4 volts? These issues have all been taken into consideration.<br /><br />The coils design can also be affected by the engines design RPMs. Simply stated, the faster the coil fires, the faster it needs to recharge. This is known as rise time. A coil with less internal resistance charges faster. So does a coil with less windings. This faster coil also produces less secondary voltage, requiring a hotter, faster firing plug. A hotter plug causes undue stress at higher RPM/load settings., so the entire system is a compromise, designed to work most effectively for your engine.<br /><br />Next factor in durability, and cost to manufacture, and you have most of the equation for the reason your ignition is built the way it is. It sure makes Dons reason to use the right part look good! Doesnt it?<br /><br />I know I have missed something, but alas, I am out of breath and its surely someone elses turn to take a shot at this one.<br /><br />Now I sit back and wait for the customary Fishflogging! ( ANYONE HAVE A COMMENT? )<br /><br />Does anyone have the time? Ah... self-employment.... the work is never done!<br /><br />Hey Trog! If you're still out there... here's to ya pal!
