What do the letters and numbers on a spark plug mean?

What do the letters and numbers on a spark plug mean?

The heat rating is a measure of the amount of heat dissipation. The heat range of a spark plug is the range in which the plug works well thermally. The heat rating of each NGK spark plug is indicated by a number; lower numbers indicate a hotter type, higher numbers indicate a colder type.

What do the letters mean on NGK Spark Plugs?

The first letter of the NGK spark plug code (in this case a “D”) indicates the thread size of the spark plug. There are three spark plug thread sizes currently being used in motorcycles and ATVs. “B” indicates a 14 mm x 1.25 pitch size, “D” indicates a 12 mm x 1.25 size and “C” indicates a 10 mm x 1.0 size.

Which NGK plug is hotter?

NGK indicates the heat range in the middle of the plug number. For example, BCPR6ES-11 has a heat range of 6. (The number after the “-“ is the gap.) Starting with part # BKR6E-11 (heat range 6), a colder plug would # BKR7E-11 (heat range 7), a hotter plug would be # BKR5E-11 (heat range 5).

How can you tell which spark plug is hotter?

The higher the number, the hotter the plug. The lower the number, the colder the plug. Starting with part # 24 (heat range 4), if you want a colder plug you would use part # 23 (heat range 3), for a hotter plug you would use part # 25 (heat range 5).

Are NGK Spark Plugs pre gapped?

While most NGK spark plugs are pre-gapped, there are occasions when the gap requires adjustment. Care must be taken to avoid bending or breaking off the fine-wire electrodes. If the gap must be adjusted, use a tool that only moves the ground electrode and does not pry between or against the electrodes.

What does NGK R stand for?

you are correct it stands for resistor.

Is NGK better than Denso?

Denso plugs are installed on almost every automobile model manufactured in Japan. The iridium used in them has a superior hardness. The electrode’s diameter in Denso plugs shrinks more than an NGK. For this reason, Denso plugs do not last longer than NGK units, but they are better at producing powerful sparks.

What is a hotter plug?

A hot-type spark plug has a longer insulator nose. The insulator nose of a hotter spark plug has a longer distance between the firing tip of the insulator and the point where insulator meets the metal shell. The heat range must be carefully selected for proper spark plug thermal performance.

Do I need a hotter or colder spark plug?

When making spark plug heat range changes, it is better to err on the side of too cold a plug. Running too cold a plug can only cause it to foul out, whereas running too hot a plug can cause severe engine damage.

What is the difference between NGK and NGK R spark plugs?

Registered. Not sure if this has been answered but the only difference between the NGK and NGK-R is the R stand for resistor. It will supress electrical interference with electronics.