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NGK Spark Plug Co., Ltd and NGK NTK - products and history


Also referred to as ‘NGK NTK’ or simply NGK, NTK being the technical ceramics side of the business, the two parts making ‘The Twins’. A brief history of NGK NTK follows:

  • On November 11th, 1936 the NGK Sparkplug Co., Ltd was set up to produce spark plugs in Nagoya, Japan. Production began in 1937.
  • In 1949 NGK was listed on the Japanese stock exchanges where company capital was increased. The manufacturing of technical ceramics also began this year.
  • Production of ceramic cutting tools and inserts began in 1958, NGK also began production of their first copper cored spark plugs this year and opened their first overseas spark plug manufacturing facility in Brazil the following year.
  • Sales offices, NGK Spark Plugs (USA) ,Inc. opened in 1966 , and NGK Spark Plugs (UK) Ltd. Almost ten years later, in 1975.
  • In the early years, in the UK, NGK spark plugs were largely shunned in favour of established brands such as Champion, Lodge, AC and KLG. This preference and bias has gradually changed over the years, many well established brands becoming obsolete and Japanese brands such as Denso and NGK gaining a reputation for dependability and quality.
  • Between 1970 and 2000, NGK opened facilities in Malaysia, Thailand, Indonesia, Ecuador, Germany, Australia, Canada, France, Taiwan and Mexico. Since 2000, facilities in Singapore, China, India, Philippines, Vietnam and the Middle East have been added to the NGK NTK portfolio.
  • In 1982, with the widespread implementation of catalytic converters and increasing emphasis being placed on emission control systems, Lambda sensors were introduced to the NGK NTK product range.
  • 1997 saw NGK put their first Iridium alloy tipped spark plugs into production, a significant advance in ignition technology allowing extended service life without compromising spark plug performance.

Products in the NGK NTK range available from Sparkplugs Ltd:

  • Standard Copper Cored spark plugs. A basic replacement suitable for older engines. These plugs may have a single or multiple ground electrodes – which can help to increase service life. All commonly requested parts are permanently kept in stock.
  • OE replacement Platinum and Iridium tipped spark plugs. Suitable for more modern engines where efficiency and service life are potential issues. Platinum types usually have a platinum tipped centre electrode and may also have a platinum pad or chip in the ground electrode to extend service life, there may be multiple ground electrodes to further increase service life. OE Iridium types will normally have an Iridium alloy tipped centre electrode and a platinum chipped ground electrode for extreme service life, a plain ground electrode is used for some models where service life is not so critical. All popular parts are kept in stock.
  • Iridium IX spark plugs. This is the NGK aftermarket replacement range of Iridium alloy tipped spark plugs. Suitable for replacing standard copper cored spark plugs where improved ignition performance and extended service life are desired. May also offer an upgrade to OE platinum spark plugs in some instances. As a general rule, if the OE part for your vehicle is an Iridium spark plug then it is unlikely that an Iridium IX spark plug will offer any significant benefit. We always keep the entire Iridium IX range in stock.
  • NGK racing spark plugs. There are two varieties currently in production; a range of older designs which may have nickel, gold palladium or platinum centre electrodes and standard nickel alloy or solid platinum ground electrodes, mostly suited to motorcycle engines. The second type is always prefixed ‘R’ to suggest a racing spark plug, e.g. R7436-8, the trailing number (‘8’ in this example) always denotes the heat range of the plug. There are a variety of designs in the range covering a wide variety of applications, most have an Iridium centre electrode teamed with a variety of ground electrode designs. Please contact us if you require assistance in identifying a suitable part. We keep the most popular parts in stock, other parts are normally available within 1 – 2 working days.
  • Standard glow plugs. Standard metal sheathed glow plugs for automotive applications.
  • Ceramic glow plugs. Offering improved heat up performance, reduced emissions and extended service life.
  • Spark plug caps. Also known as plug connectors or plug covers. We stock a variety of NGK designs constructed from EPDM rubber, silicon or phenolic resin, with or without resistors. Suited mostly for motorcycle and small engine / garden equipment applications.
  • NTK Lambda Sensors. Also known as Lambda probes, Oxygen or O2 sensors. Most modern cars need at least one correctly functioning Lambda sensor to maintain acceptable engine performance and emissions. It’s very common to see a dashboard fault code which indicates a faulty or out of service limits Lambda sensor, the only solution is to replace with a new item. NGK NTK produce a wide range of OE replacement sensors, remove the old sensor and replace with the new, no cutting or soldering required. We offer hugely discounted prices and currently a 1 – 2 day turnaround on NTK Lambda Sensor orders.