Magnum intake drilling plate project

Jadaharabi said

I have been drilling dry with a cordless drill.
I used the same bit for all 12 holes.
I am using spray grease on the tap.

I did manage to finish those last two holes up at about 4 in the morning.

Click to expand...

Cast iron, at least that which is used in blocks and heads, is pretty easy to drill. THE WARNING is when the drill breaks through on the other side. The drill can "catch" and break a chunk---sometimes a fair sized one---out of and around the exit hole. You don't want to just "slam" out the other side