What about the "shoulder"? The distance between the last thread and the start of the slope of the cone? I would imagine that would play a factor too cause even if you angle is the same but the the shoulder is longer you'd deform the button head.... Just a thought...
Originally Posted by
Geo Y-Rock
Yes, the grp6 is a medium plug. the grp5 is the hotter of their selection. I emailed Mr. Drake and he told me to run the 5. I'm a tool and die mold maker. I have the precision tools to get some hard facts about the plug dimensions. I will measure a grp and an os. I work second shift so, I will post my findings in the early hours Tuesday morning when I get home from my Monday. The difference of the end diameter from .197 to 200 isn't as important as the angle. If the angle is different, that's when damage will occur. I will get the bottom of this.