Denso Iridium RACE Plug IW01-32

Iridium Racing plugs are ideal for racing and tuned-up engines. Because racing engines do not have standard specifications it is important to select the appropriate plug type. Generally, electrodes that project into the combustion chamber have better ignitability and better performance. However, because of more exposure to high temperature combustion gases and as the ground electrode becomes longer, heat resistance and durability decrease. The higher the level of tuning, the greater the need to use a less projecting type. As the level of tuning increases, so does the need for a higher heat range.