What Size Plugs for O2 Sensor Holes?

[rd]

What size thread are the O2 sensor hole in the H-pipe?

I have a new x pipe, and my carbed 79 does not need O2 sensors.

Thanks.

 

[SVT32VDOHC]

Everytime I delete O2's from the car I just leave them in as a dummy sensor, that way it looks factory. Oh but your carbed.....umm....I went to a local muffler shop and they hooked me up with two for one car I did years ago. They fit right in...but don't know the size.

 

[bullitstang1313]

They are M18 x 1.5.

 

[rd]

Thanks.

I did this once before, but it's been 10 years, and all I could remember is that I got them from a display of oil drain plugs.