The spark plug provides the ignition spark that is necessary to ignite the air-fuel mixture. In addition to this basic function, the spark plug is also a good indicator if the carburetor is adjusted properly; a spark plug reading can tell you if the mixture is too lean (whitish electrode), too rich (black) or properly adjusted (light tan). A distinction is made between spark plugs with long and short threads, models with interference and non-interference, and each spark plug has a specific heat value. Cold spark plugs are more suitable for tuned engines, warm spark plugs can also be used in "normal" engines. We carry a wide variety of high quality spark plugs from manufacturers such as NGK and Bosch, as well as many spark plug connectors / caps and cables.