Size of oil gallery ports on top of heads

[Big Bore]

I know this is old news and been posted a gazzilion times, but what is the thread size for the oil line fittings into the heads? -6, -8?

 

[Magnum PD]

The hpo lines are also o-ring fittings. If your asking about them.

 

[Big Bore]

The hpo lines are also o-ring fittings. If your asking about them.

Yes, the hpo fittings, but looking for size.

 

[Powerstroke Racer]

I know this is old news and been posted a gazzilion times, but what is the thread size for the oil line fittings into the heads? -6, -8?

-5.

 

[Big Bore]

-5.

Thanks David.