With the widespread use of NGK V-Power spark plugs (NGK 5077 – ZGR5A) in E30 M20 applications, it’s important to stay vigilant about their replacement intervals. These plugs feature a smaller electrode surface area, which, while great for ignitability, tends to wear faster. As the electrode wears down, the spark plug gap increases, which can lead to performance issues.

One common symptom of this wear is hesitation under peak load — typically noticed in second gear around 4000 RPM during aggressive acceleration. While many assume that peak load occurs at highway speeds or near redline, live Air Flow Meter (AFM) data shows that the highest load actually occurs in second gear at about 4000 RPM.

Regular inspection and timely replacement of your spark plugs can help you avoid this performance drop and keep your engine running smoothly.

This entry was posted on May 24, 2025 at 9:30 pm and is filed under Interesting Stuff. You can follow any responses to this entry through the RSS 2.0 feed.