I just got my 79 SA running last weekend thanks to a carb from drozhenbane. This carb came from a later model RX-7 seeing that it has the attachment for the cruise control cable and my original carb didn't as well as other small differences. When I had my old carb hooked up, there was a vacuum line that ran from a "plastic bulb thingie" on the passenger side below the plastic throttle body shield up to the carb. On the new carb, I can't find a place to hook this line up. Is this vacuum line important or can I cap it off?

 

if ya can get a pic, that would help, but if not ill have a look when i get home.

 

I am borrowing this pic from 64mgb. I am not sure where the vacuum line circled in red is supposed to go. I couldn't find a place on the newer carb for it to connect to. What is the part that is circled in green and can it just be capped off?

 

I want to say that that part is removed during rats nest removal. Rich (64mgb) would be a good person to ask since he has an SA. Its been so long since I removed my emissions equipment that I am not sure if a later car had that or not. Looks familiar for some reason...

 

Anyone know what that vacuum line is for and what the black thing is that it connects to?

 

That's the air control valve, the tube usually attaches to a spigot on the bottom of the air filter housing.

 

The tube was attached to a part on my old carb like was shown in the picture. I am wondering if it is needed for the engine to run right.

 

Pretty much, yes. It's part of the emissions system and works in concert with the airpump, thermal reactor, and air-injectors.

Install a proper header and you can do away with all that garbage. The resulting simplification makes life a lot easier.