(Almost) Everything You need to know About Spark Plugs

Curious what other spark plug rituals people may have… some individuals I know use a different or old plug in the morning when warming up their engine (warm up on stand vs warm-up/heat 1 etc…). once thats done they switch it out for their “race day” plug. guess it saves any wear and gives a better reading when you look at the plug after.

Simplicity and cost. For newcomers, it means they can run those plugs with confidence.

For competition: As soon as “driver up front” throws a short, stubby $40 plug in their engine, all of a sudden others think it’s the hot ticket. surface discharge is a another good example.

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If it’s colder ambient temp then I’ll switch to a “hotter” plug, but otherwise I don’t change the plug until it needs to be done. Same plug for practice, race, etc.

I’ve got some BR10EG plugs but my cap already have the 5K Ohms resistor.

I know that it’s suggested to avoid it, but can I still use them on my X30 considering that I’m not racing but only club driving? Or I may damage something?

the most important thing is the number on the sparm plug. In NGK, 1 is the hottest and 12 is the coldest. In a so hot day, you will run the coldest spark plug, and in a cold day you will run a hottest spark plug. I like to use B9EG, B10EG ans B11EG. I use them because is easy to find here in Brazil, but I think that are better performance options on the market.

I recently ran in a new X30 engine with an NGK 9 spark plug. I’ve done multiple practise days since and months later it’s now middle of Summer. I tested on the weekend on a 36 degree celsius day, probably the hottest day of the year, still running the 9 spark plug. Will going to an NGK 10 make much of a difference or is it negligible?

You won’t notice a change in performance but it might buy you a little headroom on jetting if you go a little leaner than you need.

You’re definitely at greater risk of preignition with the 9 with temps that high if you’re running the engine hard.

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