My home inspection of Speedmaster heads

12many said

I threaded in an Autolite 3924 and no the strap just barely protruded. Those thread ends are exposed. Me, I’d have hit them with a sanding roll and reduced the sharp edges for obvious reasons. Additional Cc’s be damned, maybe others can opine as to whether it is of no concern, or otherwise.

Click to expand...

yes I just checked my spark plugs and I used to run those Autolite 3924 so as well.. I tried one heat range hotter this year and used in NGK V Power 8..
Thank you for that tip all address that as needed.. also I'm wondering if this is more of a concern with cast iron than aluminum?..
I grabbed the two different plugs and took a picture real quick while I was out checking what I am running I forgot it's been a few months now.. and for some reason I can't find the book that I write them down in.. also I pulled the cover and looked inside my car and gave myself a shock as I forgot my seats are at the reupholstery shop...

the next Heat range up is still pretty cold and insulator is still inside.. just not down in the hole..