Hi
Yes according to my Red book a 1//8th NPT thread has 27 teeth per inch
I have 2 or 3 of those, you are more than welcome to have a lend of 1 if you don't want to spend a pile of dosh on a tap set that might never see use again.
Also got a good stock of 8.4mm drill bits, quite welcome to have a lend of one at the same time.
Hope that is some help to you