Resistor spark plug converted into a non-resistor spark plug (with pictures) - PeachParts Mercedes-Benz Forum

JamesDean · #11 01-27-2014, 06:13 PM

Some useful info from NGK:
http://www.ngksparkplugs.com/docs/tech/design_symbols_plugs.pdf

I see no mention of nickel core. All the websites I looked at said copper core.
NGK 7732 BP5ES-11 Nickel Spark Plug

Quote:

A standard spark plug traditionally uses a nickel-alloy outer material fused to the copper core. Some plugs include a coating or pad of precious metals such as iridium or platinum to extend plug life. But as a general rule of thumb, all spark plugs utilize a copper core.

Quote:

Copper
Nickel is a hard, inexpensive metal used in most all spark plug designs. Nickel is not a good conductor and has a high level of resistance, so most center electrodes feature a copper core, covered in a nickel-alloy. This creates a balanced, team effort where the copper core conducts electricity and promotes heat dissipation, and the nickel-alloy outer material prolongs the life and durability of the Center Electrode.

Quote:

Nickel
While nickel is a choice material used in the majority of spark plug designs, it has its limitations. Tungsten and Iridium, for example are 2x harder and 3x stronger. Gold and Silver have minimal electrical resistance in comparison to nickel. And Iridium, Platinum, Rhodium, Titanium, Tungsten and Zirconium all have a higher melting point. Some of these precious metals are used to enhance nickel electrodes to prolong a plugs life in high performance designs.