Anyone recognize this Holley metering block?

[Clelan]

I bought a car and a bunch of parts the other day. Been going through the parts and I found this Holley metering plate. This bolt in the side is something I've never seen. Anyone know what it is all about?

Cley

 

[mopowers]

Isn't that the ported vacuum port? Looks like someone just plugged it.

 

[Clelan]

No, it's way too big for that i think.

Cley

 

[RustyRatRod]

It's ported vacuum. On older Holleys, they used a larger, threaded port with a nipple fitting that screwed in. Someone just used a bolt to plug it.

 

[Hysteric]

Interesting emulsion locations. Must be a metering block from an OEM carb.