Racing Plugs 3939

[NGK R7376B-10 Racing Plug 3939 ngk r7376b-10-3939]
Racing plugs, recommended for both two-wheelers and four-wheelers, are available in various types aimed at further performance improvement when used in races, circuit driving, or with engines that have increased output due to tuning.
Therefore, their shape differs from the manufacturer's standard plugs, and plug life and low-speed performance may be slightly compromised.
However, on the other hand, they are developed and designed to fully exhibit performance and withstand even highly tuned engines and very severe operating conditions, with a detailed range of heat ratings.
Please select the appropriate plug for your individual engine to fully unleash its performance.
Points to note when choosing racing plugs
Determine the screw size, plug type, and shape from the part number of the genuine plug or the plug you are currently using, and select the corresponding type.
Please refer to the manufacturer's website for guidance on how to choose the ignition end shape.
The heat rating needs to be selected considering the increase in combustion temperature due to engine output improvement and operating conditions, in order to maintain the plug's ignition end temperature within the optimal range.
Simply increasing the heat rating alone will not improve engine performance.
For mainly street use, numbers 7 to 8 are generally used, for track day specifications, numbers 8 to 9, and for race specifications, numbers 9 to 10.
Regarding the presence or absence of a resistor in the plug, there is almost no difference recently due to the improvement in ignition system performance.
From now on, resistor-type plugs will become the mainstream.
Conversely, with non-resistor type plugs, there is a risk of engine trouble in some models of some vehicle types.
In such cases, please be sure to use a resistor-type plug.
*The image is for illustration purposes, and the design and specifications of the products shown may change without prior notice. Thank you for your understanding.