The Dinan D640-0001 Iridium Spark Plug is a heat range 9 performance spark plug for Gen 1 B48, Gen 1 and Gen 2 B58, and S58 BMW engines. Its iridium center electrode and copper core are designed for durability, efficient heat dissipation, and consistent ignition under high-boost, high-cylinder-pressure, and high-temperature operating conditions.

Dinan specifies this plug as one step colder than OEM for the listed B48, B58, and S58 applications. It can be used on tuned or stock vehicles when the application, plug size, heat range, and gap are appropriate. The supplied gap is 0.5 mm, with a 26.5 mm thread reach, 12 mm thread diameter, 14 mm bi-hex, and flat seat.

The D640-0001 is designed to pair well with Dinan ignition coils and is optimized for demanding fuels and performance applications. Dinan specifies an installation torque of 17 Nm and recommends verifying plug dimensions, gap, and heat range before installation.

Dinan currently lists this product as not legal for sale or use in California because CARB testing is pending. Verify current emissions status and vehicle applicability before ordering.