NGK COLDER SPARK PLUGS N55
1-Step Colder Spark Plugs for BMW N55 Engines
NGK SILZKBR8D8S (97506)
Recommended for anyone running above stock boost. Ie. anyone running JB4, Cobb, etc.
1-Step Colder Spark Plugs for BMW N55 Engines
- Copper tipped core with iridium coating for low wear and great conductivity
- 1-step colder heat range for high performance and tracked N55's
NGK and offers 2-step colder spark plugs for the BMW N55 engine. These colder spark plugs are recommended for N55's who are running higher than stock boost. The 1-step colder plugs will likely need to be changed every 15,000 miles, on heavily modified cars, or sooner if the engine is experiencing rough idling, longer starts, or misfiring.
The stock heat ranges on the N55 are one-step lower than the N54, therefore these plugs are one-step colder for the N55, and two steps colder for the N54.
Why Opt for 1-Step Colder Plugs?
It should be noted - running colder spark plugs will not necessarily increase power (although it may restore power if the current plugs are old). These spark plugs are not recommended for stock boost as the spark plug will not retain enough heat to burn carbon deposits, thereby significantly reducing the life and effectiveness of the plugs. If your BMW N55 is modified, tuned, FBO, etc., the 1-step colder spark plugs are the best option. These spark plugs are more efficient at transferring heat and reducing the likelihood of engine knocks or pre-detonation, which becomes a concern at higher boost and horsepower levels.
NOTE: These spark plugs need to be individually gapped to 0.020" (0.508mm) using a spark plug gapping tool. Additionally, these are the OEM plugs for the N20 and N26 turbocharged four-cylinder engines.