Replacing spark plugs with new ones can indeed improve a vehicle's speed, but the effect is mainly reflected in the optimization of power output rather than a direct increase in top speed. Spark plugs of different materials exhibit significant performance differences; for example, iridium spark plugs have an ignition energy approximately 30% higher than ordinary copper-core ones, which can further shorten the combustion cycle and improve the linearity of power output. However, spark plugs have limited effect on increasing top speed, as a vehicle's maximum speed depends more on engine design, ECU tuning, and transmission system matching. It is best to check the condition of spark plugs every 30,000 to 60,000 kilometres. If the electrode gap exceeds 1.3mm or carbon deposits are present, they should be replaced promptly. Choosing high-quality spark plugs that match the original factory specifications (such as NGK or Denso brands) can not only maintain the engine's optimal operating condition but also avoid fuel waste caused by poor ignition, resulting in a long-term fuel consumption reduction of about 5-8%.
