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NGK WIRE SET IGNITION CABLE TYPES AND DESIGN

COPPER WIRE CORE IGNITION CABLE WITH SHIELDED CONNECTORS

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This type of ignition lead consists of galvanized copper wire cable, 7mm in diameter. The radio interference suppression is located close to the source of the interference and is thus built into the spark plug & distributor connectors (metal resistor boots). NGK Wire Sets for this type of ignition system only use OEM (or better) 29ga. galvanized copper wire cable with the required OEM spark plug and distributor resistor boots as specified by the Original Equipment Manufacturers! This type of system is primarily used on European makes such as; Alfa Romeo, Audi, BMW, Mercedes-Benz, Porsche, Volvo, and VW.

DISTRIBUTED RESISTANCE IGNITION CABLE

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Sometimes also referred to as "Carbon-core" wire, this type of ignition lead (5, 7, or 8mm in diameter) uses a carbon-coated fibreglass core with a conductive silicone layer for resistance. This type of cable has been used by most of the OEM makes since the 1950s and even today, (while largely being replaced by magnetic wire wound cable), still is original equipment on some vehicles. NGK Wire Sets for this type of ignition cable utilize a superior conductive silicone layer for lower resistance values than OEM wires. The conductive silicone layer also offers maximum protection against high temperatures, while providing excellent RFI noise suppression.

MAGNETIC CORE WIRE WOUND IGNITION CABLE

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Sometimes also referred to as "Mag-core" wire, this type of ignition lead (5, 7, or 8mm in diameter) has been original equipment on certain vehicles since the early 1970s, but became more widely used through the mid-80s to early-90s. NGK Wire Sets for this type of ignition cable use a premium alloy winding, over Ferromagnetic coating to deliver ultra-low resistance (far surpassing OEM wires), more powerful spark, and outstanding EMI/RFI noise suppression. The reinforced Kevlar® / Aramide* core provides maximum tensile pull strength of the cable & long-life durability.

COMMON IGNITION WIRE INDUSTRY PROBLEMS

Below are eight commonly observed examples of wire sets that require replacement due to damage, mis-installation, or inferior product design. These problems and the associated probable causes for each are listed as a guide to help diagnose and avoid similar problems in the future.

Problem Terminal fused to plug
Problem Misfiring
Problem Arching
Problem Heat & moisture contamination
Cause Inferior boot design allowed moisture intrusion
Cause Excessive amount of applied dielectric grease resulted in spark plug failure
Cause Improper installation of boot on distributor cap caused arching
Cause Condensation and lack of anti-corrosion metal caused terminal contamination
Problem Burnt cable lead
Problem Flashover inside spark plug boot
Problem Water corrosion & rust
Problem Terminal separation from cable lead
Cause Cable lead was incorrectly routed over cylinder head, causing damage to outer jacket
Cause Spark plug without insulator ribs was used, causing flashover to occur
Cause Inferior distributor boot allowing moisture to enter and cause terminal oxidation
Cause Poor quality ignition wire and terminal combination susceptible to pulling strains

*Kevlar® is a registered trademark of E.I. du Pont de Nemours & Company, Inc.