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Dead Parrot · 06-06-2020, 10:45 PM

IMO - The things to keep are PCV, THERMAC, and the charcoal fuel vapor capture setup. And maybe the exhaust riser valve coupled with the intake crossover.

PCV - does a lot to keep oil clean and is one of the most effective of the earlier pollution controls. Simple and is already figured into the carb setup.
THERMAC - really helps with cold weather warm up and preventing carb icing when temps are somewhere around 30s~60F and high humidity. Also simple.
Charcoal canister mostly gets rid of the raw gas smell from the gas tank vent.

The exhaust riser valve - intake crossover does help with warm up but if the valve sticks shut, it can cause the intake to get very hot and result in carb damage.

In your pics, looks like the EGR is already missing. And some of the AIR pump hoses.

06-06-2020, 10:45 PM	#3
Dead Parrot Registered User Join Date: Aug 2012 Location: Oklahoma City, OK Posts: 2,675	Re: Another smog thread IMO - The things to keep are PCV, THERMAC, and the charcoal fuel vapor capture setup. And maybe the exhaust riser valve coupled with the intake crossover. PCV - does a lot to keep oil clean and is one of the most effective of the earlier pollution controls. Simple and is already figured into the carb setup. THERMAC - really helps with cold weather warm up and preventing carb icing when temps are somewhere around 30s~60F and high humidity. Also simple. Charcoal canister mostly gets rid of the raw gas smell from the gas tank vent. The exhaust riser valve - intake crossover does help with warm up but if the valve sticks shut, it can cause the intake to get very hot and result in carb damage. In your pics, looks like the EGR is already missing. And some of the AIR pump hoses.