Sometimes when chasing the head bolt holes on Chevy blocks, you’ll hit a casting knob. Then you think, will the bolt thread in far enough. I use a 7/16 valve guide and some washers to mimic the cylinder head thickness. This saves time by not having to measure every time it’s in question. The outer bolt holes on Big Block Chevy’s seem to be the worst.
Randy Torvinen
Torvinen’s Machine
Menahga, MN
