I know there are other spark plug threads out there, but none like my intentions for this one.

I have been reading about and playing with spark plug gap for some time now, and it honestly does affect performance. I wanted to try to compile honest experience from members who have done the same, to see the results for better understanding and suggestions of settings and why people choose their specific setup for plugs.

For a quick overview of how spark plug gap relates to real world performance:
http://www.custom-car.us/ignition/spark-plug/gap.aspx

For example, I believe stock suggestion is .028 gap. Most people run a .032 gap, and use a step colder range, ie BKR7E. I have loved the copper plugs and that's what I use, plus they are like $8 a set, but need to be replaced around 5k miles if not sooner.

I bought two brand new sets of plugs. One I gapped to .037, the other at .04. I ran the .037 gapped plugs for about 2k miles. Then, I swapped in the .04 gaps for another 3k or so miles. Then, I swapped the .037 back in, and the difference is pretty amazing.

In my results, both .04 and .037 felt more powerful than .032. During this time, I never did any other modifications. But, the difference was that with the .037's I have quicker power in lower RPMs, and 2nd gear is amazingly strong. With the .04's, there is less immediate punch, but there is more power stretched through the RPM range.

The link above states that timing has a direct relationship with spark plug gap as well, but it doesn't explain it. In my opinion, I believe that timing can be tweaked to produce better and better results unto a point where you run out of potential. Question is, how?

I have REVO tuning, where you can adjust timing on a scale of 0 - 9. Setting 3 being the suggested notch for 91 octane fuel. I run with it on 4, yet still only run 91 oct. 93 is very scarce in the mountain regions. If I had true 93, I could run on 5 or maybe 6 for timing.

Regardless, if you have had good experiences with spark plug gap in your life, post your results. I'll go first.


Sent from my porcelain throne.