Busting the Copper Spark Plug MYTH
It’s common knowledge that copper plugs are the best choice for all engines. Right? Well, there are a few caveats, so the legend goes. First, everyone knows they don’t last as long as platinum or iridium. But the improved performance you get from copper plugs is supposed to make up for the more frequent changes. If only that myth were true.
It isn’t!
Vehicles with distributorless ignition systems (DIS) fire the spark plug from the center electrode on the firing cylinder. But to complete the electrical path back to the ignition coil, the return electricity must jump from the SIDE electrode back to the center electrode on the firing cylinder’s “partner.” According to Autolite engineering team, “although copper spark plugs may function well initially, they are not designed to handle the needs of a DIS engine and will likely fail prematurely.”
The engineers add, “Copper core single platinum spark plugs are not designed to withstand this reverse polarity firing and will suffer premature gap growth due to center electrode erosion. Gap growth will stress ignition system components by requiring more voltage to fire,” said Dave Buckshaw, Honeywell CPG trainer for the FRAM® and Autolite® brands. “This degradation can be noticeable as soon as 20,000 miles after the plug is installed.”
Buckshaw adds that many consumers don’t realize that very few new vehicles still use copper core spark plugs and those that do – like the Chrysler® 5.7 Hemi V8 – specify a 30,000-mile spark plug change interval.
Double Platinum plugs are specifically designed for engines with DIS systems and are 30 percent more durable than the average of leading competitors. The platinum-to-platinum firing offers virtually no gap erosion and performance that lasts for up to 100,000 miles. Autolite’s proprietary platinum alloy and welding process on the Double Platinum plugs provide superior engine performance, longer life, improved fuel economy and easier starts.
Autolite XP Xtreme Performance® spark plugs designed with an iridium-enhanced .6mm finewire are also compatible with DIS engines. These ultra-premium plugs require less voltage to fire and have a faster flame kernel growth in the combustion chamber resulting in a better, faster, more efficient burn compared to the .8mm finewire, multi-electrode design and standard plugs. Not only does this increase fuel economy, but, according to Autolite engineers, igniting more gas and air mixture inside the cylinders will result in improved throttle response and acceleration.
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© 2007 Rick Muscoplat
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