Racing Plug 3949

【NGK R6254E-105 Racing Spark Plug 3949 ngk r6254e-105-3949】
Racing spark plugs, recommended for both two-wheeled and four-wheeled vehicles, come in various types designed to further enhance performance when used with engines that have increased output due to racing, track driving, or tuning.
Consequently, their shape differs from standard manufacturer-specified plugs, and there may be a slight compromise in plug lifespan and low-speed performance.
However, conversely, they are developed and designed to fully demonstrate their performance and withstand even highly tuned engines or extremely severe operating conditions, with a detailed range of heat ratings up to very high values.
Please select the appropriate plug for your individual engine to fully unleash its performance.
Precautions for choosing racing spark plugs
Please check the thread size, plug type, and shape from the part number of your genuine plug or the plug you are currently using, and then select the corresponding type.
Please refer to the manufacturer's website for guidance on how to choose the firing end shape.
The heat rating needs to be selected to maintain the plug's firing end temperature within the optimal range, taking into account the rise in combustion temperature due to increased engine output and operating conditions.
Simply increasing the heat rating alone will not improve engine performance.
For mainly city driving, heat ratings 7-8 are generally used; for track days, 8-9; and for racing, 9-10.
In terms of the presence or absence of a resistor in the plug, there is almost no difference recently due to the improved performance of ignition systems.
Resistor types will become the mainstream going forward.
Conversely, non-resistor types may cause engine trouble in some vehicle models.
In such cases, please be sure to use a resistor type.
*The image is for illustration purposes only. The design and specifications of the products shown may change without prior notice. Thank you for your understanding.