Exhaust EGR plug size for 1978 280Z

[dankfrye@charter.net]

My EGR tube on my 1978 280Z has a bad exhaust leak where it comes out of the manifold. The past owner tried to repair it with metal tap but that obviously didn't work too good. I want to take it out and plug the hole in the manifold. I've done a lot of research on the correct plug size but can't seem to get a common
answer. I've heard 22mm, 3/4 NPT Brass and several others. Does anyone know the correct plug that I need?
Thanks'
Dan

[ZCurves]

Dan,

Is this something that you really want to do? What about just replacing the tube/fitting instead? The work effort is about the same and you would avoid some potential funky stuff with the rest of the EGR, EFI setup. I think I have some spares.

On the other hand, you could change your intake to a '75 model and eliminate all kinds of EGR garbage -Still need to plug the manifold though unless your using headers.

My 2 cents.