Vacuum port size

[Vinnie]

Hi,

Does anybody know the size of the vacuum ports on the Edelbrock Performer lb351c-2v intake? I want to plug one off.

Do I need some kind of rubber O-ring for it as well?

Thanjs,

Vincent.

 

[rocket366]

post a photo of the port you speak of to narrow down your question.

Paul

 

[Vinnie]

Tapatalk gives an unknown error when posting the pic.

The LB351-2V intake only has 2 similar vacuum ports. Surely somebody knows what size plug I need to close it?

 

[barnett468]

Look inside the holes . If they go straight through and remain the same size as the threads all the way thru, they are pipe thread . From the looks of them in photos, if they are pipe thread they are likely 1/2" pipe thread but could be 1/4" . You could buy both if the store isn't close to you.

If you see a convex [domed or cone type] seat inside the holes, they are not pipe thread and require an inverted flare fitting.

 

[73pony]

They look like 1/4" to me but hard to tell. Barnett is right on with the Pipe thread Vs Flare. You could take a tape measure to it to get a rough idea.

 

[basstrix]

The plug is PROBABLY 3/8" NPT, but I am not certain. If you can give me a measurement of the OD of threads on whatever is in there now, I can confirm.

 

[barnett468]

If they are pipe thread, you must buy a plug that states a SMALLER size than the hole . Yes this sounds odd but that's just the way they do it.

If it is not a pipe thread hole, buy the fitting that is the same size as the hole.

1/4" hole .......... 1/8" pipe plug

1/2" hole .......... 1/4" pipe plug

3/4" hole .......... 1/2" pipe plug