Do I need to set the "gap" when installing a new set of plugs? - NGK Spark Plugs (2024)

FAQs

Do I need to set the "gap" when installing a new set of plugs? - NGK Spark Plugs? ›

Maybe. A spark plug part number might fit hundreds of different engines from many different manufacturers. Although the NGK factory will set the gap to a preselected setting, this may not be the right gap for your particular engine.

While plugs are pre-gapped from the factory, the gap may need to be adjusted for the vehicle that the spark plug is intended for. Those with modified engines must remember that higher compression or forced induction will typically require a smaller gap setting (to ensure ignitability under higher pressure).

When you don't have the proper spark plug gap, that can lead to premature wear, ignition system stress, and even cylinder misfires. The space between electrodes must be wide enough to create a sufficiently energized spark.

All NGK spark plugs are pregapped from the factory. It is recommended that you double check the gap on any spark plug before installation to assure the proper gap for your application.

The gap between the center and side electrodes of a spark plug must be an exact distance; otherwise, your plugs don't fire efficiently. Adjusting the distance between the two electrodes is called gapping your spark plugs. You need a feeler gauge to gap your spark plugs properly.

Although the NGK factory will set the gap to a preselected setting, this may not be the right gap for your particular engine. The incorrect plug gap for your engine can contribute to a high rate of misfires, loss of power, plug fouling, poor fuel economy and accelerated plug wear.

In most cases your Iridium Power plugs do not need to be gapped. Even with small variations in the factory set gap the ultra-efficient firing power design will compensate for those small variations.

Autolite^® and all spark plug manufacturers offer spark plugs pre-gapped in the most popular gap sizes.

Most spark plug manufacturers will pre-gap their spark plugs for their most popular application but considering that same spark plug might fit over a hundred different vehicles or engines, checking that it matches your vehicle's specifications is always a good idea.

Is Dielectric Grease Necessary for Spark Plugs? Strictly speaking, dielectric grease is not necessary for spark plugs to function; however, as noted above, it is a cheap, easy-to-use material that helps ensure the current moves through the spark plug into the ignition system.

Are NGK good spark plugs? ›

NGK makes some of the best spark plugs out there in my experience and they are less pricey than some of the other top brands. They always perform well and never disappoint. These are top of the line plugs in my book. These are a steal at this price.

Why Are Iridium Spark Plugs So Expensive? Iridium spark plugs cost more than other varieties because of the scarcity of iridium itself. Iridium is an extremely rare metal that is only mined in certain locations, and global supply has been severely affected by travel and processing restrictions during the pandemic.

Do Spark Plugs Always Have to Be Gapped? Not always. In the past, it was necessary to gap spark plugs, but today spark plugs are usually pre-gapped. It is advisable to double check that the gap is correctly set to the vehicle's recommended setting when installing spark plugs.

For example, the NGK spark plug BKR6E-11 will have a gap of 1.1mm (. 044”). Below is an example of the specifications of a spark plug that have been decoded to tell us what specific features this spark plug may include.

Naturally aspirated combinations tend to perform better with a hotter plug that's gapped from 0.030 to 0.035-inch. Conversely, forced-induction and nitrous-assisted mills are happier with cold spark plugs gapped at 0.020 to 0.025-inch.

To put it simply, the gap is the space between the central and side electrodes. This spacing is pivotal, dictating the spark intensity, which is crucial for efficient combustion. Vehicle manuals provide the ideal gap, which usually ranges between 0.028″ and 0.060″.

Refer to your owner's manual or contact your vehicle's manufacturer for more information. Q: Are ACDelco spark plugs pre-gapped? A: Yes. When ACDelco spark plugs are manufactured, they are pre-gapped to the correct gap specification.

Under normal operating conditions, expect a good 100k miles out of these plugs.