250ci 6 Cylinder Emissions Questions.

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Ghetto

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Hello everyone. Looking for a little bit of info. I plan on ditching the charcoal canister and plugging the lines except the tank vent line. My question is can anyone tell me what any of the items circled in orange are and if/how they can be deleted?

Thanks in advance..

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Ghetto

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Charcoal canister has been ditched and a direct vac source for the vaccum advance is in place (5 more psi than the way it was ran before)

Truck runs and idles way better now. I know the rear hump is the PCV valve. The front one just looks like some sort of breather type line that goes to the air filter assembly. I will probably leave that intact.

Would really like to know what the bottom item that is circled (Decel Valve????) as well as the top left thing circled. It's a little plastic thing with 2 vac lines connected to it hanging in mid air (EFE????)
 

foamypirate

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My 1984 C10 came with a 250, and I think it still has the emissions sticker on it. If I get a chance, I'll try to get out there today and get a picture and see if we can figure out what those are.
 

CorvairGeek

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It is a deceleration valve, I assume you have a manual transmission. The differential pressure between ported and non ported vacuum causes it to open upon deceleration, which helps prevent fuel from being pulled from the carburetor causing higher HC & CO emissions.
The rest of it (in the valve cover and the check valves attached) are part of the pulse air system. It uses the pulsations of the engine to induce air into the exhaust system for HC & CO control, instead of using an air injection pump.
The item on the upper right is a thermo vacuum switch (TVS) which switches vacuum sources to the outputs (which could be the distributor vacuum advance, the vapor canister, and the pulse air system) depending on the temperature of the engine.
You mentioned EFE, Early Fuel Evaporation. On the 2 barrel 250 only, the EFE system is an electrically heated grid under the base of the carburetor. IIRC correctly, you can only see the grid under the primary side of the carburetor if you look down through the carb with the throttle wide up. Don't believe there is a grid under the secondary side. It only operates when the engine is below a certain temperature. It is for drive-ability and to help protect the catalytic converter from rich mixtures when the engine is cold.
EFE is a heat riser system on V8s
 
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Ghetto

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I still have my emissions sticker. It's where I found efe etc. I in fact have a 3 speed on the column. So cam that black plastic looking thing circled top right with the 2 vac lines attached be tossed?
 

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