Spark plugs have been around as long as internal combustion engines have and are often a misunderstood component. An Iowa native, Smith served a variety of roles at Car Craft before moving to the senior editor role at Hot Rod and Chevy High Performance, and ultimately returning to Car Craft. Your ignition system will thank you for your attention to detail. Place a small amount around the inside of the boot. Be especially careful if you’ve made aftermarket modifications to your engine. A spark plug gap gauge is a disc with a sloping edge, or with round wires of precise diameters This is a used plug from a small-block Chevy that had started out with roughly 0.040-inch gap and the copper core has worn to 0.050-inch. Drove With the Parking Brake On Accidentally: Now What? These three spark plugs are all tapered seat, projected nose yet when lined up at the seat, they are three different lengths. If you want another example, there’s the 350 hp Focus RS turbocharged four-cylinder Ford engine that pushes as much as 25 psi of boost, and it also employs an iridium plug. While the spark still occurs, it can retard the timing by as much as two degrees. Your order may be eligible for Ship to Home, and shipping is free on all online orders of $35.00+. DDDenny, Sep 10, 2018 Autolite offers the X-series of plugs that has slots cut in the end of the plug, creating sharp edges that make it easier for the spark to jump the gap. With a traditional copper-core plug, the center electrode will wear much more quickly and the gap will increase. Even with late-model fuel injection and data logging, reading a spark plug is still a viable art that is an important part of tuning. All Rights Reserved. Iridium Spark Plugs. I used a 5/8" spark plug socket, 3/8" ratchet wrench, a 1.5" extender and a locking 3" extender (which helps to get the socket back out after tightening a plug). I used 2 hands when I … Some wires are made to produce minimal resistance. Gasoline-powered engines come in different shapes and sizes, but they all require three essential elements: air, fuel and spark. This basic guide is designed to assist the technician, hobbyist or race technician in understanding, using and troubleshooting spark plugs. All rights reserved. As power from late model engines continues to escalate, selecting a spark plug that will live and not contribute to problems becomes a much more difficult assignment. This compares an extended-nose plug (left) to a standard-reach plug (right). Then multiply the Ohms per inch by 12 to get the Ohms per foot. Learn why it’s important to keep this part of your car in great working order and when to change spark plugs by watching for these bad spark plug symptoms. Compare Accel 9000C Universal Ceramic Spark Plug Wires, Straight, Extreme 9000. It’s important that the metal core is highly conductive, heat resistant and hard enough to keep its shape under the stress of the combustion process. As an example, the supercharged production 2018 Dodge Hellcat—which makes 707 hp from its 6.2L Hemi—specs an iridium spark plug. This often is a result of dyno test data where the colder plug appears to work just fine. There’s a war being fought out over the internet right now – and the first victim in this explosive war of words is the truth. Check out all the electrical & ignition system products available on NAPA Online or trust one of our 17,000 NAPA AutoCare locations for routine maintenance and repairs. Over time, however, engine heat takes its toll on even the best spark plug wires, which is why changing spark plugs and wires is recommended by many manufacturers at 100,000 miles. Firing Order Swaps: What’s Best For Your Engine? A “hot” spark plug lengthens the depth of the ceramic which lengthens the distance from the center electrode end of the plug to where it contacts the spark plug shell. While a standard gap of 0.035-inch works well for naturally-aspirated engines, if the plug wires are in good shape and the ignition is strong enough, many naturally-aspirated engines might benefit from a slightly wider gap of 0.045 to perhaps 0.050-inch. Why Do We Measure Engines Against The Power Of Horses? The spark plug also has a steel jacket, which allows the threaded end of the plug to be torqued into the cylinder head. The center electrode’s precious-metal material does not contribute to the heat range, nor is it a factor with regard to pre-ignition. C.O.P. © Copyright National Automotive Parts Association. Left) There’s nothing wrong with a standard copper core spark plug, and some power-adder tuners prefer these plugs for helping tune. The disadvantage is this will concentrate the spark on one side of the center electrode. Whether you’re seeking replacement wires or aftermarket performance wires, we have everything you need. We removed the threads on these two plugs to illustrate heat range. Like platinum, it’s used on the end to fortify the electrodes for longer life. We should also define the term “copper core” when talking about spark plugs. Spark plug companies don’t recommend anti-seize on threads because it lowers the torque required to install the plug. Most competition engine builders commonly choose a colder heat range plug to prevent possible engine damage. The metal center of spark plugs is exposed only on the ends. Dispelling The Spark Plug Myths. Jeff Smith, a 35-year veteran of automotive journalism, comes to Power Automedia after serving as the senior technical editor at Car Craft magazine. A wider gap increases the load on the ignition system, demanding higher voltage. Sealed Up: Total Seal’s Quick Seat Piston Ring Lubricant, Video: On The Dyno With Edelbrock’s Gen-III Hemi Cylinder Heads, A Guide To Ford V8 Engine Block Casting Numbers, 1952-1996. The addition of precious metal in the center electrode has nothing to do with the heat range of a spark plug. (Right) Sometimes a shorter spark plug can improve clearance with tight-fitting headers. Now part of Holley Performance, ACCEL offers a comprehensive selection of … The colder plug on the right has a much shorter path for the heat to travel; it pulls heat more efficiently from the plug tip so it will not burn off carbon as easily. This grease is an insulator not a conductor. All rights reserved. Once you have read the resistance of the wire, divide that number by the length of the wire (inches) and this will give you the Ohms per inch. This Denso plug is called a U-Groove referencing the U-shaped ground strap. Harder than platinum, Iridium plugs came on the market in the mid-2000’s as … This may not seem like an important consideration, but install a standard reach small-block Chevy plug (like the one you can barely see here) into a longer-reach chamber like this iron Vortec head and the spark becomes shrouded and power will suffer. © 2020 Power Automedia. We’ve seen a 20 hp loss from incorrectly installed plugs like this on a 500 hp engine. Is threaded into the combustion chamber the Myths and old wives ’ tales surrounding the spark plug.... Easily than a colder heat range engines and especially supercharged, turbocharged or nitrous applications will demand a plug! And only send content you request housing, usually made of porcelain Accel 9000C Universal ceramic spark plug wires,! Replace old plugs, first consult your owner ’ s precious-metal material does not remove as much two. The difference between 7mm spark plug fires as the length of the spark still occurs, does. 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