What size hole???

[98bluevert]

I am putting on a PI intake with alluminum crossover on a 98 GT and need to know what size hole to drill for the second sensor

 

[98bluevert]

ok so i have done some searches and have come up with using a 9/16 bit or a 21/32 bit anyone know which one i am suppose to use along with what tap.

 

[forum155pl]

3/8-18 NPT Tap.... dont forget the NPT part!

 

[98bluevert]

ok got that but what size drill bit 9/16 or 21/32 have been told both

 

[forum155pl]

i forgot the size drill bit.. it will ususally say on the package for the Tap..

 

[98bluevert]

will the local hardware store have a npt tap or where can i get one

 

[DropTopPony]

9/16 works fine.

 

[forum155pl]

i got my tap from sears i think it was like $11

 

[98bluevert]

thanks for the help i'm using a 9/16 bit and i ordered a 3/8"-18 npt tap.