Table of Contents
What spark plug size do I need?
Most spark plugs require a 5/8″ (16mm) size spark plug socket. This refers to the size of the flats on the spark plug that are in contact with the socket. 3 of 3 found this helpful.
Should spark plugs be the same size?
While you should buy spark plugs in matching sets for your vehicle, not all spark plugs are universal. Spark plugs come in different sizes with different gaps and are manufactured using a variety of metals.
What are the 2 sizes of spark plugs?
While 5/8″ (16mm) and 13/16″ are the two most common plug hex sizes, plugs can have a hex as small as 8mm or larger than 1″. If you’re a tuner or engine builder in search of the perfect spark plug for your current project, pay special attention to the hex size required.
What happens if you use the wrong size spark plug?
If you install the wrong size, the tips of each spark plug could make contact with the pistons inside the engine, which can cause extensive damage. A warm or hot engine could damage the threads. You will also need to check the spark plug gap if the spark plugs are not already pre-gapped.
What size are metric spark plugs?
Metric threads spark plugs according ISO 28741
| Size | Major Diameter (mm) | Pitch (mm) |
|---|---|---|
| M10 x 1.0 | 10.0 | 1.00 |
| M12 x 1.25 | 12.0 | 1.25 |
| M14 x 1.25 | 14.0 | 1.25 |
| M18 x 1.5 | 18.0 | 1.50 |
How do you match spark plugs?
Replacement spark plugs must be the same size as the original (same hex size, diameter, thread pitch and length), and have a similar “heat range” (hot enough to resist fouling when the plug is cold, and cool enough to resist pre-ignition when the plug is hot).
Can I use a regular socket for spark plugs?
You can use a regular socket, with that being said you need to be very careful. A spark plug socket has a washer on the end so that socket is always sitting fully down and straight. With a regular socket you will have wobble at the top.
Does the length of spark plug wires matter?
What is even more imperative than matching cable length is that you do not mix up the order of the spark plug wires. Improper installation of these wires can result in poor combustion or misfiring of the cylinder, which will cause drivability issues and potentially severe damage to the engine.
Can I use a different spark plug?
All spark plug manufacturers cross-reference their plugs with other brands so their brand can be interchanged with other brands. In other words, any brand of spark plug can be used in any vehicle make or model application assuming the plug has the correct dimensions, design and heat range.
What are the different spark plug thread sizes?
Identifying NGK Spark Plugs
| Letter | Thread | Pitch |
|---|---|---|
| D | 12mm | 1.25mm |
| E | 8mm | 1.00mm |
| G | PF 1/2″ pipe | |
| AB | 18mm | 1.50mm |
Do different spark plugs make a difference?
This would be more accurately described as “less performance loss.” Spark plugs do not increase the performance of an engine — even spark plug manufacturers are fairly forthright about that. They won’t make the engine perform better than it did when it was new, but they will help it stay at that level longer.