help me understand emissions

[seannz28]

I've got an 82 carbed z28, I am taking apart the engine right now to rebuild it, and everything is pretty basic, (this is my first hands on with a carbeureted motor, efi is way different. all these hoses and components. what do they all do, in terms of vacuum hoses and stuff coming off the smog pump, etc etc.?
When I got it all off, everything else makes sense, heads, intake, carb, water pump, alternater....blah blah blah. But this emissions control stuff baffles me. thanks

[Rob B (shoebox)]

I don't know specifics on that particular car, but if you plan to keep it for a while, the best thing you could do is buy a factory manual for it. Everything is explained in detail. Look on Ebay or online stores that sell used manuals.

[Detroit_Bird]

IMHO I would remove all those emissions functions from the car and replace the carb and intake- it simplifies everything and makes it look cleaner. Emissions routing in the 80's was a nightmare.

[markd79ta]

That stuff was mid-evil!!!!!!! On your thermostat, you will see two plastic pieces called thermal switches. You have vacuum running to these from the quadrajet. When the motor reaches the right temp, these switches allow vacuum to go to your EGR and the butterfly in your snorkel on the air-cleaner can as well as the actuator to open the butterfly in your passenger side exhaust manifold. You have the hoses coming off the air-pump to your manifolds, and a diverter when you decelerate so you don't get the snap, crackle, pop in your exhaust. You also have vacuum line and hoses from the carb running to your charcoal canister. It is all pretty retarded! The thermal switches die so you don't have the butterflies opening when they should. I had this motor in an old '81 Camaro. I put in a regular thermostat housing and routed a direct line to the butterflies and EGR...It ran much much better! If you need an emissions test, leave the thermostat housing and drop the vacuum lines next to the carb and don't connect them...they will never know the difference. It isn't that bad once you trace everything. It is a lot better then some of the others out there at that time.