Forum » General Tuning Discussion » Spark plug gap on the larger end, any gains to be expected?

Spark plug gap on the larger end, any gains to be expected?

General Tuning Discussion

Discuss all things tuning in this section. News, products, problems and results. 

Page 1

Following up on Andre's webinar on plugs, I am curious to hear if there are positive effects to be expected by running larger gaps.

Provided the spark energy is sufficient to not run into a misfire situation, should we opt to gap at the widest side ?

Thanks for sharing your opinions


I think I covered this within the webinar. My own experience has been that I've yet to see a gain in power from a larger plug gap. Theoretically there is some potential for improvement but this just isn't something I've seen on the dyno. I wouldn't however say that my testing has been extensive so I can't state with certainty that it won't show improvements on some engines.

The flip side however is that any gain that you may see would be instantly eliminated if you have a misfire due to that wider plug gap under high load. The key really is to test and see what works. While I'm an advocate for reasonably tight plug gaps, I wouldn't do so needlessly - You need to experiment and find how tight you need to gap your plugs to eliminate misifres in your particular engine and work around this point.

Thank you Andre !