Damn Dave, that's a lot of technical info.there. All good and compelling points. Not that you have any errors in your above post, but as a layman, I just don't see how any air,mist can escape to anywhere. There's no hole at the bottom of the threaded gear shaft hole, is there? No. And there's no hole in the head of bolt; how can it escape? What is the travel path? Is it traveling up through the threads? My position on this matter is based on my recollection from this very debate several years back, along with Rob @ Needswings stated opinion on this matter. I see now, that initially and for quite some time, Rob didn't have the hollow bolt, but now he is offering it. You can buy the inexpensive solid bolt, or pay $18. +sh. for the hollow bolt. I would think that if the solid bolt was detrimental to our S.C.'s, that Rob would not offer the solid bolt?
Do I believe you, or Rob our XF guru? Check out Needswings.com / SRT6 / Supercharger/ SC pulley bolt