Tap for temp sensor in PI manifold

[H What 4.6]

Ive read to use the 3/8-18 NPSF tap but my father has a 3/8-18 NPT tap ....

I looked the two up and both are pipe thread taps but i believe the NPSF is straight through and the NPT has a slight taper to it.....

I believe the NPT should work fine with some silicon around the threads but can anyone verify??

before anyone says its not necessary ....... i already have my autometer gauge in the plug in the block so thats not an option

 

[Winters98GT]

you want to use the NPT

 

[deftsound]

i have heard of people tapping into the thermostat housing as well