In '76 anyway, all L82's came with a pump but not L48's...just Cali..
Smog Pump
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Instructor
Joined: Jun 2012
Posts: 220
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From: Trophy Club Texas
Smog Pump
I'm trying to figure out this smog pump thing on the later C3s. Is it just a California requirement? And if it has a smog pump, is it a 305? Are those cars something to stay away from buying? There's a ton of C3s out there. I see the smog pump on some of them.
Le Mans Master
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Race Director
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From: Virginia
Do you live somewhere that requires a smog pump? If not, a PO did you a favor.
The only 305s in C3s were 1980, California-delivered, LG4 engine option cars.
https://corvettec3.ca/engines.htm
They also came with the computer controlled carb, the bane of all 81 cars, too.
None of this is hard to fix, as long as you are allowed to.
The only 305s in C3s were 1980, California-delivered, LG4 engine option cars.
https://corvettec3.ca/engines.htm
They also came with the computer controlled carb, the bane of all 81 cars, too.
None of this is hard to fix, as long as you are allowed to.
Le Mans Master
Joined: Sep 2002
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From: Myrtle Beach SC
But in the 1970s, the role of air-injection reactor or A.I.R. (smog pump) was to inject oxygen into the exhaust to complete combustion...unspent fuel through inefficient carburation entered the exhaust. The role of A.I.R. is to burn that unspent fuel. Higher horse power engines (L82s) require more fuel...thus more air to complete combusion...thus high-HP motors are equipped with A.I.R. whereas low-hp (L48s) are not. This varies by model year. California with the strickest emission control standards, led the way. Later high-altitude got on the band wagon and required A.I.R....I guess less air up in the mountains!
Computer controlled air/fuel ratios nearly eliminate unspent fuel and the need for A.I.R. Look at C8 engines producing 490 horsepower...try to find that smog pump!
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From: Sunshine Coast, Queensland, Australia
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Simple answer, No. The smog pump is not something to be afraid of or steer away from.
As can be seen in the answers above, generally the higher output engines got the air pump. Not just the one year only California car.
You live in Texas, just rip it off! Plug the holes or install headers and move on.
As can be seen in the answers above, generally the higher output engines got the air pump. Not just the one year only California car.
You live in Texas, just rip it off! Plug the holes or install headers and move on.
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Safety Car
Joined: May 2004
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From: los altos hills california
https://www.dmv.ca.gov/portal/vehicl...og-inspections,
Wish I could remember the assemblyman who sponsored this?
Safety Car
Joined: Oct 2004
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From: Youngstown Ohio
That's not completely true. Post 1975 California cars are required to have their emissions equipment and are (or were) inspected for compliance. That probably includes catalytic convertors. I haven't checked up on that lately so this is merely cautionary. See this link.
https://www.dmv.ca.gov/portal/vehicl...og-inspections,
Wish I could remember the assemblyman who sponsored this?
https://www.dmv.ca.gov/portal/vehicl...og-inspections,
Wish I could remember the assemblyman who sponsored this?