Many years ago before there was this Internet thing I drilled the steam holes in an 848 head.Did it hand holding a drill while securing the head between by feet.This head went on a 261 that ran perfectly for several years.Many other guys I know did the same.
Then somewhat recently old GM info comes up showing the steam holes in the 261 heads were drilled at a 12 degree angle facing the port side of the head.
This is what I think;some castings may vary,perhaps the actual 261 head is cast slightly different internally.Or all the guys who drilled straight got lucky.
Let's take a poll on who here has drilled the steam holes themselves.Ask if they drilled straight in,then ask if they ruined a head.
