stock......but while were on the subject of plugs, is there any sort of engine mod that could possibly cause a change in the gapping size of the plug? i guess what i'm asking is, what determines the gap size of a plug?

 

Two things, both have to do with engine design, how big of a flame are they trying to light at once, and how much power does the ignition system have, for a high revving overbore motor, with hot ignition, a nice wide .06-.08 gets things cooking fast. If the ignition can't support that then smaller, or if it's a low revving or extra long stroker the gap may be narrower.

I havne't looked into it for many years but "Jacobs ignitions" used to be on top of things.