I've got an sb2 intake which was previously used with a direct port nitrous set up. I need to plug these holes as i'm staying n/a for the time being. My question is what size (thread, diameter, pitch) is a nitrous direct port nozzle usually. It looks about a 5/16" to me, but the thread is not coarse or fine, is there any other sizes? Thanks.

 

should be 1/8 NPT

 

That small huh, maybe these holes weren't for nitrous then? I'll try to get in touch with the guy I got this stuff from. thanks.

 

1/8 pipe doesnt measure 1/8. its more along the 5/16 you are reffering too on an actual outside measurement.
good luck.

 

Oh, ok. Well then a 1/8 pipe plug may work then you think? Thanks for the help!