Autolite busts myths: switching spark plug brands does not decrease engine performance

Jan. 1, 2020
“There is an unwarranted fear that switching brands might lead to decreased engine performance, but this is really a myth. The engine does not know what brand of plug is being installed, it only knows if a good plug is being installed,” s

Research conducted on behalf of the Autolite brand suggests that many DIYers and professional technicians think that a vehicle’s engine actually gets used to a certain brand or style of plug, and are therefore more hesitant to change brands.

“There is an unwarranted fear that switching brands might lead to decreased engine performance, but this is really a myth. The engine does not know what brand of plug is being installed, it only knows if a good plug is being installed,” said Rick Widden, vice president, Ignition and Filtration for Honeywell Consumer Products Group. “The most important factor in ensuring proper engine performance is that a motorist or technician uses the right type of plug.”

For professional technicians and DIYers unsure which plug type to install, here is a basic guide provided by the Autolite technical team:

  1. Install Autolite Copper Core plugs in older passenger cars and trucks (20-plus years old) with conventional ignition systems and cast iron cylinder heads.
  1. For older vehicles with aluminum or iron heads, the Autolite team recommends an upgrade to an iridium-type plug like the Autolite XP Xtreme Performance spark plug. Featuring a plated shell, the plugs help prevent seizing in the heads.
  1. For domestic vehicles with DIS ignition systems, technicians or DIYers should use Autolite Double Platinum as standard, or upgrade to Autolite XP Xtreme Performance plugs for additional performance benefits.
  1. Older Asian and European vehicles (built between the early ’80s and the mid-’90s) with alloy cylinder heads and overhead cams, require a plated shell plug. “The Autolite XP Xtreme Performance spark plug makes the most sense since they are efficient and tend to be easy on older ignition systems,” said Widden.
  1. For newer Asian and European cars that feature distributorless ignition systems and coil on plug engines, an iridium-enhanced or double platinum plug is ideal.
  1. Install a finewire plug like the Autolite XP Xtreme Performance spark plug on newer General Motors vehicles that use finewire technology.
  1. Ford uses several different electrode types on its newer vehicles, so installing Autolite Double Platinum or XP Xtreme Performance® plugs is ideal since most of their engines also feature alloy heads.

  2. Chrysler vehicles still use a lot of plated copper core plugs with standard electrodes. The Autolite team does not plate its copper core shells so it strongly suggests an upgrade to a Double Platinum or XP Xtreme Performance plug for certain applications.
New line of ignition wires and insulator boots

In other Autolite news fromAAPEX, the comapny is introducing 44 new part numbers for its line of ignition wires and insulator boots to provide a broader range of coverage to the industry.

With 22 new SKUs, Autolite Professional Series Wire Sets are designed for use in distributorless ignition systems. They meet or exceed OES design requirements by providing the necessary silicone content, boot design and accessories (i.e. retainer clip, heat shield, and extension bases) where required. The high-tech nylon reinforcement in the wire provides increased terminal retention and improved jacket adhesion. The new SKUs will increase the Autolite brand’s coverage to 98 percent of all vehicles on the road that require ignition wires.

The brand has also dramatically increased its insulator boot offerings. Coil On Plug (COP) ignition systems are on the rise and the Autolite Professional Series Coil On Plug insulator boots will meet increasing demand in this fast growing parts replacement category. The Autolite COP insulator boots feature durable silicone rubber EPDM boots, as well as contact springs, terminals and resistors for specific applications.

“By 2010, about 80 percent of new passenger vehicles will leave the factory with COP technology. The additional part numbers will help provide professional technicians with the parts needed for carrying out service and repair on now aging COP systems,” said Widden. “We now have coverage for approximately 70 percent of the vehicles on the road today that feature COP technology.”    

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