I think I finaly figured out why I'm getting 7 mpg.. after reading some old posts about vacuum leaks i went out the checked my car and can you guess what i found? yup a vacuum nightmare, so maybe you guys can help me out here, this is whats going on..
theres a hard line coming out back of the carb that gose into a small black plastic can looking thing, then comes out the other side of it and gose to the master cylinder. then theres a hose that gose from the intake manifold to what looks like a rounded box on the fire wall (drivers side), then 2 hoses come out of that and go into the fire wall on the passenger side, from there i don't know where they go... now on the front of the carb there are 2 ports farthest to the right, those are pluged, and all the way to the left theres a port and its also pluged. then there is a hose going from the PCV valve(i beleave thats what its called, its in the vavle cover) to 2 ports in the front center of the carb (the 2 ports are above and below each other) and from then runs to some vacuum diapham on the passenger side of the carb (i'm not sure what its for).. this is on an 84' 305 with a stock cc-carb, please help.. i'm lost right now..

 

Here's what it's supposed to look like.

This diagram doesn't show the cruise control hookup, or the one that works all the vacuum-operated doors that control air flow in the dash. Those come off of a fitting on the manifold behind the carb. There's a vacuum accumulator that prevents vacuum from just going away when you floor it and all the doors going back to their rest position; you should have a line going from the intake to the larger hose nipple on that, and then the line that comes through the firewall by the heater hoses should hook to the other, smaller hose nipple on it.

The cruise is a whole stand-alone vacuum system all by itself, not connected to anything else, that just has one connection to get its vacuum from a port off of that fitting on the manifold.

 

RB83L69, thanks for the pic, i moded it and this is what it looks like now..

 

Doh.

 

hope this works

 

The EFE, which I am guessing is "something to do with the choke", is the heat riser valve, at the outlet of the right manifold. It should not get continuous vacuum. It's supposed to get vacuum only when the coolant is cold. Supplying vacuum to it closes it, which forces the right bank exhaust to all have to go across the top of the motor, under the carb, and into the left bank manifold. Once the coolnat gets up to 120° or some such, the EFE TVS should close, which lets the valve open back up, and exhaust flows normally. So if you have that hooked up like it is in your drawing, your heat riser valve is closed 100% of the time the engine is running, which isn't a good idea.

 

no, theres nothing going to that valve on the manifold, its a part of the carb, its a vacuum diapham with linkages hooked up to the electric choke.. the only things that i have are shown in the pic