Started tapping a hole in my aluminum slant manifold but the tap was about one inch too short. What is used to tap deeper? I need to go down about 3 1/2 inches. What do you guys use?
You need a long tap or drill the hole out 1 size larger than the barrel of the tap and just thread the bottom. You will still run into a issue because tap extensions (so you can get to the bottom of the hole) are fairly large.
