Ignition Leads & Caps

Q: What is an ignition lead?

Also known as an ignition cable, ignition leads (which consist of an ignition wire and connector) link the ignition coils to the spark plugs. Ignition leads form part of one of the four product lines offered within the NGK Ignition Parts brand. Thanks to NGK SPARK PLUG's competence in the field of ignition technology, the company is able to offer ignition leads and connectors in the Aftermarket that are OE equivalent quality and ideally complement its wide range of spark plugs and ignition coils.

Q: How many different types of ignition leads are there?

There are three different types of ignition leads: Copper Core Ignition Leads with an interference suppression resistor (in the connectors), Carbon Ignition Leads with active resistance, and Fibreglass Ignition Leads with an inductive resistor. These types differ based on the materials used for the conductor and the type of resistor required for interference suppression. It is important to choose the correct technology for any specific engine, leading to the ideal performance of the ignition system. The company’s ignition leads meet the OE standards of car manufacturers.

Q: Do NGK ignition leads make a difference?

NGK ignition leads guarantee outstanding insulation, a high level of resistance of up to 200°C and resistance to vibrations and fluctuations in temperature and humidity. Choosing the brand’s ignition leads secures permanent reliability under extreme conditions, even over an extended period of time.

Q: What role do caps play?

Caps are mainly required for motorcycles, scooters, small engines and marine applications. They are used to connect each spark plug to a high tension (HT) ignition lead; typically by screwing them onto the end of the cable. Occasionally, caps can be applied to 4-wheel vehicles as well, in which case they are usually pre-assembled. The caps feature a resistance element made of a high-quality ceramic material. This ensures a constant resistance, with small deviations in case of overload. The housing is made of phenolic resin with extremely high heat resistance and tensile strength. Special rubber bushings at both ends prevent electrical losses due to moisture.

Q: Is there a difference between NGK caps and resistor caps?

Caps, both with and without resistance, are available in NGK SPARK PLUG’s product range. The resistances vary between 1-10 kiloohms (kOhm), filtering the electromagnetic interferences. To choose the correct application, it is necessary to check the part that needs to be replaced and then change accordingly.

Efficient High Voltage Transfer

NGK ignition leads are a key element in the ignition system of many petrol engines. They connect the ignition coil to the spark plug. NGK SPARK PLUG offers ignitions leads and caps that perfectly complement its wide range of spark plugs and ignition coils.

Up to 1,000 ignition leads available

More than 92% coverage of vehicles in operation (source: TecDoc)

High-protection insulation against chemical and electrical environments

Withstand highly demanding conditions

NGK Ignition Leads & Caps Technologies

There are three different types of ignition leads. These types differ based on the materials used for the conductor and the type of resistor required for interference suppression. It is important to choose the correct technology for the specific engine. Only this will lead to good performance of the ignition system. Our part finder helps to find the correct technology. NGK ignition leads' technology meets the OE standards of car manufacturers. The NGK SPARK PLUG product range for ignition leads includes:

Copper core ignition leads with interference suppression resistor (in the connectors)
Carbon resistor ignition leads
Ignition leads with inductive resistor

NGK SPARK PLUG caps are equipped with a resistor element made of high-quality ceramic materials. This ensures a constant resistance value with only slight deviation during overload conditions. The casing consists of a robust phenolic resin with extremely good resistance to heat and tensile stress. Special rubber bushings on both ends prevent electrical losses from moisture.

Requirements on Ignition Leads & Caps

There are three requirements that top-notch NGK ignition leads need to fulfill: Firstly, outstanding insulating characteristics, secondly a high level of resistance (up to 200°C) and finally, resistance to vibrations and fluctuations in temperature and humidity. If the ignition leads meet these requirements they can offer permanent reliability under extreme conditions - even over an extended period of time.

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