Excuse my simpleton question but i cant seem to find the information im looking for online. I recently switched to a carb setup, i have a quadrajet 4 barrel, ive got one fuel inlet at the front of the carb, but there is also a fuel inlet/outlet at the rear of the carb.

So is it a extra inlet to plumb sum more gas like the edelbrock or holley carbs, or is it a return? thanks, Joshua

 

There is no fuel fitting at the back of the carb.

 

If it's the fitting/threaded hole on the back of the throttle plate, that probably for the PCV valve hose.

 

I think the fitting you're referring to a the rear of the carb is for the power brake booster line.

 

should i plug it if its just for pcv, since i already have a vaccuum line for the pcv connection. The brake booster is off of my intake manifold. or should i just leave it open? i just went from not sure to puzzled? i will take a picture of it tomorrow. thanks Joshua

 

If you're not going to connect anything to it, plug it. It'll be a huge vacuum leak if you don't.

 

heres what im talking about, ive looked at pictures and see a hose running from it but the picture executes before i can see where it goes. THnkas. Josh

 

Power brake booster.

 

That is a flare fitting and will be hard to plug. Best to remove the flare adapter from the base and install a 1/4" pipe plug in the hole that's left.