You sound quite knowledgeable about the details of the ignition. People tend to mix and match all kind of parts on these cars. I would think that heatgrade 5 might be better on a relatively stock engine spec.
The 5 might be better or too hot. If it only gets used for city driving then id go with 5. The best answer comes from driving a tuned engine and checking condition. Then reassessing the heat grade based on your driving conditions.
You sound quite knowledgeable about the details of the ignition. People tend to mix and match all kind of parts on these cars. I would think that heatgrade 5 might be better on a relatively stock engine spec.
The 5 might be better or too hot. If it only gets used for city driving then id go with 5. The best answer comes from driving a tuned engine and checking condition. Then reassessing the heat grade based on your driving conditions.