Originally Posted by montecarlo84
has anyone tested this on a dyno?
I just stick'em in .
http://www.eatonbalancing.com/blog/2...plug-indexing/
Granted, they're talking about Ford engines, but it's still a decent article.
If you use a plug with a crush washer, you can mark the ground strap or gap side of the plug (depending on which you want to see), and then tighten it, crushing the washer until the mark lines up where you want it.
If you have a taper seat plug, using tapered seat indexing washers will be required.
http://www.summitracing.com/parts/MO...0/?image=large