my holley 6210 quadrajet model has a fitting at the back of the carb that is plugged but it is called a gulp valve. i believe it's a vacuum source. can i use this for my power brake hose. my edelbock manifold location is blocked by the secondary mechanical pump.

 

If you can find a way to hook it up, go for it. Anything vacuum on the secondary side is going to be full manifold vacuum.

 

thanks, so this is full vacuum, do you know why was it installed in the first place and called a gulp valve.

 

Not sure what it is or why it's called that, but if you post a picture of it I could probably figure out what it does.