The Best Spark Plugs for Vehiclesby Contributing WriterUpdated June 12, 2017
Vehicles first glance, spark plugs seem to perform a fairly simple task: to create a gap allowing an electrical arc to ignite compressed air and fuel. While almost any piece of copper wire could perform such a job, spark plugs need to do it dozens of times per second under some truly intense conditions. But while many companies claim to produce Vehicles plugs, enhancing Vehicles actually comes down to choosing the right plugs Vehicles your engine and application.
Under The Hood:
- The Best Spark Plugs for an Audi TT 1.8T FWD
- The Best Spark Plugs for Gas Mileage
- The Best Spark Plugs for a Ford 5.4 Engine
There are, in fact, 11 spark plugs that you can substitute effectively. These include the Autolite APP3923, the Beru 14F-6DPUR02 or the Bosch F7DPP222T. You can also use the Champion OE136, the Daihatsu 9004851166000 or the Denso PK20PRP8. The Eyquem RFC58LZDP, Fiat 60569957, Mitsubishi MS851346 and Unipart GSP9652 also effectively substitute for the NGK plug. Finally, you can use the Motorcraft AGPR12PP8 to keep your Audi TT running efficiently.
Standard spark plugs use a steel band set a short distance from a steel tip. The electrical arc jumps from the tip to the band, which is grounded to the cylinder head. Steel is a decent electrical conductor, but iridium, platinum and copper are better. Better electrical conductivity means a stronger spark and better fuel economy, but do your homework. Many of these iridium/platinum/copper-tipped spark plugs come preset with a standard-sized gap from the manufacturer, which (combined with the material's more efficient energy transfer) can actually produce a smaller and weaker spark than stock plugs. You may need to widen the spark plug gap to take advantage of the material's increased efficiency and see any noticeable improvement in mileage.
Hotter Range Plugs
All spark plugs use some sort of ceramic insulator (the white part on the plug) to contain heat inside the combustion chamber. A shorter insulator allows heat to radiate out and keep the plug tip cooler; a longer one keeps the plug hotter and enhances combustion efficiency, throttle response and mileage. If you do most of your driving around town, don't have a high-compression or turbocharged engine and don't do much racing, then you might want to consider installing a "hotter" (longer insulator) spark plug. A hotter spark plug tip will also allow you to run a little more plug gap for increased spark size and efficiency.
There are a lot of spark plugs on the market today with two or four ground straps. Such spark plugs are often inaccurately referred to as "multiple-tip." There's only one tip, but multiple ground straps allow the spark to follow the path of least resistance. This can be a boon to engines with a comparatively weak distributor or single-coil ignition system, where multiple ground straps will help to ensure that the spark plug fires every time it's supposed to. However, engines using powerful coil-on-plug or direct ignition are typically better off using a single, wide-gap iridium/platinum/copper-tipped plug. Multiple ground straps can actually impede flame travel and efficiency, so don't use them unless you really need to.
The new Motorcraft spark plug for the 5.4 Triton engine, the MC SP507 platinum plug, replaces the old plug, PZT14F. The SP507 is one piece and has a little more durability. The design prevents fouling at low engine speeds, and is self-cleaning at high engine speeds. The old PZT14F was designed in two pieces, and would have a tendency to break off in the head due to carbon buildup on the seat. The newer plug tends to be more durable in the torque stress. The lack of carbonization buildup with the newer model aids in removing used spark plugs. This spark plug was made for the Ford owner who wants to stick with original equipment.
According to Drew Shippy, a spokesperson from Champion, "The new Champion 7989, another one-piece design, has greater durability and is the hottest-selling spark plug Champion has.” The Champion 7989 has a double platinum design, and withstands the carbon buildup characteristic of the 5.4 Triton engine. Its one-piece design addresses the problem of breakage during removal, and the superior heat-active alloy prevents excessive carbon buildup. The Champion is crimped and laser-welded to form one piece.
Autolite makes the HT-1.5, which was designed to be more durable than the HT-1. This single platinum spark plug was the Autolite answer to plugs breaking in the 5.4 Triton engines. According to Autolite, the original plug was redesigned for enhanced durability and power. Autolite designed the HT-1.5 to run hotter. Hotter-running plugs do not corrode and foul, and are self-cleaning. The spark plug continues to be a two-piece design, but incorporates a nickel plating to prevent corrosion and carbonization. The old Autolite plugs were designed with copper sheath and threads, which were prone to fusing and corroding.