Spark Plugs Origins
Have you ever had a teacher who, for one reason or another, just didn’t like you? Growing up, we used to call them TTs, short for Touchy Teachers.
Well, after spending the whole of last year learning online, my fifteen-year- year old baby-girl, on going back to high school for her sophomore year, found herself marked by a TTT-Technology Touchy Teacher.
Anyway, to cut a long story short, after catching my Girlie red-handed, passing around a drawing of the TTT with a sparking spark plug in his nether region, the mean man had called her a “bright spark who needed to be taught a lesson.
The end of it all is that Girlie had been given a “submit-or-be suspended” research paper on the types of spark plugs for cars and a 48-hour deadline. Girlie having been suspended twice before, and given the school’s “three suspension=expulsion” rule, I just had to help my baby-girl stay in school, by literally going back to school myself!
In this article, Girlie and I present our research findings on car spark plugs. Firstly, we briefly share with you some salient facts about spark plugs generally (i.e. what they are, interesting trivia and what their use on cars is).
Thereafter, we look at the specifications or characteristics of the different types of spark plugs currently on the market, a few specific brand examples of each type, and lastly, their advantages as well as disadvantages.
We end by looking at some examples of the different makes and some models of cars that use the types of spark plugs looked at.
Spark Plugs Uses on Car
Spark plugs are almost as old as the history of motor vehicles. Also known in British English as “sparking plugs“, they are an indispensable device that delivers current from a car’s ignition system to the combustion chamber of a spark-ignition engine.
Once there, it ignites or sets alight by an electric spark, compressed fuel/air, while containing combustion pressure within the engine island .
Spark plugs come in different materials and have varied properties. For those who, for one reason or another, are not familiar with spark plugs, we will try to describe them for you and how they are fitted into vehicles.
Spark plugs are characterised by an inner central electrode covered by a visible white porcelain insulating shell. At the output terminal of a vehicle’s ignition coil, the central electrode is connected by a heavily insulated wire.
Metal coats the electrodes. A threaded shell at the bottom of the spark plug permits it to be screwed into a vehicle’s cylinder head. The very bottom end of the spark plug extends halfway into the combustion chamber.
Spark plugs are vital for gasoline engines only. They conduct the electrical energy from a vehicle ignition system required to finalize combustion. When the gas mix has been completely compressed inside the cylinder head, spark plugs deliver a tiny spark that then lights up the mixture, creating an explosion that then drives a piston downward.
Conversely, diesel engines do not require spark plugs. This is because their higher compression ratios are sufficient to create combustion without assistance from a spark plug.
On average, about 99% of gasoline-powered engines need only one spark engine per cylinder to assist with their combustion. However, some high-performance engines, such as the Chrysler V8s require two plugs per cylinder.
Types of Spark Plugs
The type of metal used to coat a spark plug’s electrodes is how different types are known and defined. Consequently, spark plugs fall into FIVE main categories or types that come in two performance configurations-OEM style replacement and higher-performance configurations.
The types of spark plugs are Copper/-Nickel, Single Platinum, Double Platinum, Iridium and Silver.
1. Copper-Nickel Spark Plugs
Also simply known as Copper, Standard or Normal Copper spark plugs, these have a nickel alloy for the electrodes and a copper inner core-away from the extreme temperature the plug’s outer areas have to withstand.
Most types of spark plugs have copper inner cores because of the metal’s high ability to conduct electricity. They have the largest diameter of all spark plugs and so require more voltage to generate the necessary spark.
Copper spark plugs are best suited for pre-1980 makes and models of cars and perform best under high-compression or turbocharged circumstances.
Example brands and models of copper-nickel spark plugs include the:
- NGK Standard
- Denso Original U-Groove
- Champion Copper Plus
- Their high conductivity has made them a favorite of some manufacturers of high-performing late-model vehicles.
- They are cheaper than most other types.
- Natural gas engines tend to do better on such plugs.
- Have a shorter lifespan than other types-especially when fitted into modern vehicles with high-energy distribution ignition systems or coil-on ignition systems.
- Are not recommended for installation on most modern vehicles.
- Are only best suited to engines built before the 1980s, when high-energy distributor-less ignition systems were introduced.
- Require more voltage than most.
2. Single Platinum Spark Plugs
Other platinum spark plugs might not have a solid platinum centre, but rather a fine wire core with one or more platinum discs inside. This use of less platinum content is still sufficient for efficient conductivity.
Those vehicle manufacturers recommending single platinum spark plugs, advise platinum spark plug change intervals of up to 100,000 miles.
Example brands of Single Platinum spark plugs include the:
- Motorcraft Finewire
- Bosch OE Specialty
- Crown Platinum
- Longer-lasting than most as they have a longer lifespan (double that of copper ones) under normal driving.
- Harder than nickel alloy and so do not corrode as copper-nickel spark plugs do.
- Less likely to have the gap at their tip widen as the metal erodes.
- Less likely to cause a car in which they are fitted to experience a drop in power of misfire when started.
- They more effectively resist carbon build-up.
- They run at higher operating temperatures than copper-nickel ones.
- They are compatible with most modern standard engines with distributor based electronic ignition systems.
- They have long plug change intervals of up to 100,000 miles.
- That they are considered relatively expensive
3. Double Platinum Spark Plugs
So-called because of the platinum plating that features on both the centre and ground electrode, this spark plug, being “double platinum”, tends to cost more than its single counterpart and others.
They are best suited for vehicles with a wasted spark system. In such a system, each ignition coil fires two sparks simultaneously-one in the compression stroke’s cylinder and the other in the exhaust stroke’s cylinder.
The second spark in the exhaust stroke’s cylinder is often considered unnecessary as the air-fuel mixture would have already been burnt in the last stroke.
Example brands of double platinum spark plugs include the:
- AC Delco
4. Iridium Spark Plugs
Thus called because of the small iridium center electrode which requires less voltage to create a spark. This spark plug was designed for better electrical energy conductivity.
It comes in both standard OEM style replacement and high-performing configuration models such as the: Bosch OE Specialty Iridium, Denso Iridium Power, Pulstar Plasma Core Series Electrode Plus Plug, Autolite Iridium XP, HKS Super Fire Racing, RIPP Superchargers and NGK Iridium IX.
While these are expensive, it is advisable not to change to another spark plug type, as doing so might negatively affect your car’s performance.
Example brands and standard models of Iridium spark plugs include the:
- A Platinum-like lifespan and longer lasting than copper-nickel spark plugs.
- Offering power by way of more complete combustion.
- More complete combustion leads to smoother running engines.
- Require less voltage
- Being iridium, they have the highest cost.
5. Silver Spark Plugs
Named after the silver element coating their electrode tips, Silver Sparks are rarely used in the vehicles of your average Joe Public.
The reason for this could be because they are mainly used in very expensive European high-performance cars and motorcycles that few people can afford to purchase. As such, they rarely ever need them-let alone know of their existence.
Example brands of Silver spark plugs include the:
- Bosch OE Specialty Silver
- Having the best thermal conductivity.
- Not being as long-lasting as Platinum and Iridium spark plugs.
- Being less durable because silver is not.
Cars Using Different Types of Spark Plugs
When it comes to spark plugs, different makes and models do not usually have one-size-fits-all type compatibility.
Interestingly enough, while certain makes and models manufactured on a particular continent, in a particular country or car manufacturer and over a certain period might be able to use the same type(s) of spark plug(s), this is not always the case.
1. Cars Using Copper-Nickel Spark Plugs
Copper-nickel spark plugs are compatible with and still used in cars from as early as the late 1920s to the present. For instance, Ford’s 1928 Model A and some 1930s General Motors GM vehicles still use the AC Delco Professional Conventional copper-nickel spark.
On the other hand, some German makes and models of cars like BMW, Mercedes-Benz and Volkswagen use and are well-suited to OE Specialty Nickel spark plugs.
2. Cars Using Single Platinum Spark Plugs
Single Platinum spark plugs are synonymous with the Ford Motor Company’s makes and models of cars stretching as far back as 1958. An example of such a Ford car is the Edsel. Similarly, Chrysler and Mopar makes and models of vehicles like the Jeep are compatible with Crown Platinum spark plugs.
Certain German makes and other overseas cars imported into the U.S. from 1965 to the present are well-matched to, for instance, the Bosch OE Specialty single platinum spark plug.
3. Cars Using Double Platinum Spark Plugs
Comparatively longer-lasting than Copper or the Single Platinum, Double Platinum sparks have been known to be recommended for, among others, Japanese vehicles like the Suzuki Liana 1.3. Apparently, they are incompatible to Ford vehicles.
4. Cars Using Iridium Spark Plugs
Some of the car makes and models using Champion iridium spark plugs are generally American and European imports from as far back as 1946, the mid-1980s to date. Examples are the Silverado, Tahoe and Yukon.
Some Ford vehicles from 2003 to the present-day, such as 2003 Ford Mustang, Ford Crown Victoria, Ford E150 Van 2WD, Ford Escort ZX2, Ford Explorer Sport Trac also use both Platinum and Champion Iridium spark plugs.
High performing Iridium spark plugs such as the HKS Super Fire Racing kind are specifically designed for selected imported vehicles like the BMW M3, BMW Z3, Mazda RX-7, Mitsubishi Lancer Evolution, Hyundai Genesis Coupe.
Conversely, NGK Spark IX Iridium spark plugs are well-suited to the late-model Jeep Grand Cherokee SRT8.
5. Cars Using Silver Spark Plugs
Silver spark plugs are more attuned to older European performance vehicles like the Porsche, Mercedes, BMW and related motorcycles. Examples of such motorcycles are the BWM K100 and Royal Enfield 350 Bullet, from Germany and Britain, respectively.