The spark plug is the final step for the ignition process. All of the voltage and energy build up to make a final leap across the plug gap which initiates combustion of the fuel mixture.
The spark travels through the plug wire terminal to the threaded tip of the plug’s center terminal. This terminal reaches all the way through the ceramic shell of the plug and ends at the electrode. The electrode is centered in the plug with a gap between it and the tip of which is connected to the metal housing of the plug forming a ground to the engine. The voltage jumps this gap to reach ground, resulting in a spark that ignites the air/fuel mixture in the cylinder.
One physical adjustment you can make with most plugs is the distance of the spark plug gap. Opening the gap forces the coil to build up a higher voltage in order for the spark to jump the gap. Too large of a gap will also put added pressure on the secondary side of the ignition system, resulting in shortening the life of the components. Too small of a gap can make life too easy on the ignition to the point where the resulting in a weak spark that may not be strong enough to create a full combustion cycle of the air/fuel mixture.
There are a variety of spark plugs available from simple to exotic designs. And of course each one has their own theories on why one is better than the other. There are platinum-tipped plugs, plugs with tiny electrodes, some with numerous electrodes, and more. There are also spark plugs called resistor plugs, non-resistor plugs, hot plugs, and cold plugs. It is best to follow your engine builder’s recommendation for plugs, or to test and tune with gaps and different brands.
Ignitions 101| 08/14/2016
Since electricity is not something we can physically see, the ignition system of our cars sometimes holds a little mystery or suspicion in its operation. It’s important to realize that electricity, especially in an automotive setting, is not magic. And it’s also important to realize that the ignition is key to your engine’s performance. Your engine’s overall performance is counting on that spark for complete combustion. Once you have a better understanding on how the ignition works and what each component actually does, things will begin to all make sense – and you’ll be able to build the right ignition for your engine. Key goals of the ignition system:
You can have the most powerful ignition available and tuned to perfection, but without a battery to fire things up, you’ll be going no where. The battery is the main source of power for a performance ignition system, and you need to be sure that it’s capable of having the juice you need get the engine fired up. Not to mention to supply the ignition with current and voltage created by the alternator.
Hooker BlackHeart 2017-2019 Ford F150 Raptor V6, 3.5L Stainless Steel Mid-Pipe and Muffler Assembly| 04/17/2019
Hear the Hooker BlackHeart Mid-Pipe & Muffler Assembly for 2017-2019 Ford F-150 Raptor trucks.
Justin Martin's Twin Turbo Nova at OSCR VI| 04/17/2019
Justin Martin and his Twin Turbo Motion Raceworks Nova are one of the most competitive combos in the Limited Drag Radial world. We took some time to get this interview with him at the Holley EFI Outlaw Street Car Reunion!