FORDNOMORE

Hello everybody, I am planning on installing my EGT sensor this weekend and my question is what size drill bit should I use for a 1/8" NPT fitting?. Thanks in advance and Happy Hollidays!!

slighfoxs3500

I bought the tap and it said to use a 7/16 drill bit, your tap should tell you what size drill bit to use. Good Luck!

FORDNOMORE

Thanks for the quick reply. Merry Christmas everyone!

pappyman

Normally the drill size is 75% of the tap size......heres a link to tap drill sizes

http://www.newmantools.com/tapdrill.htm

HammerMTB

The tap/drill chart is great, but since it is using letter drills, I thought I'd give you the easy #. slighfox is giving you the drill size for 1/4" not 1/8".
Use 5/16". It will give you the correct thread % for 1/8" NPT, without going around looking for the letter drill.