1975 smog pump
Burning Brakes
Joined: Oct 2013
Posts: 1,114
Likes: 520
From: McClellandtown, Pa.
NCRS Judging Guides and other restoration manuals say that all 74-77's came with the AIR system except the L48's with the automatic tranny. Yet, some NCRS gurus are positive all 75's came with A.I.R system. All 75's did come with the CAT.Converter.At least I hope this answers your question about the L82. Yes it should have a smog system on it.
If you google the question, you'll be able to read some of the NCRS forum responses on this topic.
Regards,
Jim
Last edited by Tooch1; Jun 14, 2016 at 01:08 PM.
Drifting
Joined: Jan 2014
Posts: 1,866
Likes: 140
From: Sadieville Kentucky
Race Director
Joined: Oct 2000
Posts: 12,658
Likes: 3,117
From: Shamong, NJ
Starting in 1975, every new car sold in the US, came with a catalytic converter. The use of A.I.R. pumps, varied by make, model and engine.
75 L-82 Corvettes came with both a cat and an A.I.R. pump. In fact, the 75 sales brochure has an illustration in it, showing an L-82 engine with the A.I.R. pump installed on it.
There were no restrictions on engine options for California in 75. This was likely because the cat cleaned the exhaust enough, that the L-82 still met California's stricter emission levels. 75 was the last year that the L-82 was available in California. 
75 L-82 Corvettes came with both a cat and an A.I.R. pump. In fact, the 75 sales brochure has an illustration in it, showing an L-82 engine with the A.I.R. pump installed on it.
Race Director
Joined: Jul 2015
Posts: 13,082
Likes: 3,399
From: SW Florida.
since you are in PA, maybe. you are one of the few that get emissions inspected on 75's. do not ditch your cat! true duals with aftermarket cats of maybe scare up 2 OE cats from a caravan or similar may improve performance while also improving emissions.
oe 75 cat is trash. expensive scrap value but jnk.
oe 75 cat is trash. expensive scrap value but jnk.
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My early 75 L48 had AIR pump and cat, yes that's all gone.
Le Mans Master
Joined: Jan 2001
Posts: 6,722
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SMOG TEST NOT TRUE FOR 1975.
https://www.dmv.ca.gov/portal/vehicl...g-inspections/
Your vehicledoes not need a smog inspection if your:
Gasoline-powered vehicle is a 1975 year model or older (This includes motorcycles and trailers.) Diesel-powered vehicle is a 1997 and older year model OR with a Gross Vehicle Weight of more than 14,000 pounds.
https://www.dmv.ca.gov/portal/vehicl...g-inspections/
Your vehicledoes not need a smog inspection if your:
Gasoline-powered vehicle is a 1975 year model or older (This includes motorcycles and trailers.) Diesel-powered vehicle is a 1997 and older year model OR with a Gross Vehicle Weight of more than 14,000 pounds.
Last edited by carriljc; Jun 23, 2022 at 12:54 PM.
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...I believe EVERY '75 Corvette came with an A.I.R. pump, but many have argued that they have low mileage original cars and their's never came with one blah, blah, blah. 1975 & 1976 Corvettes were the easiest to make look like it never had a smog pump as it DID NOT have the typical A.I.R. exhaust manifold "trees". '75 & '76 had a single rubber hose coming off of the smog pump to a pipe connection just below the heat riser. So it was easy to make it look like it never had a smog pump once you removed it. They used exhaust manifolds exactly like a '74 L-48 automatic Federal Emission car which never, ever came with a smog pump so the exhaust manifolds won't have a place where the A.I.R. trees attached to. I've looked at a ton of 1975 Corvettes and if it wasn't all "redone or modified" and mostly original or survivorish, I could tell there once was an A.I.R. pump on it. The NCRS Guidelines "used" to say that "maybe" some did not come with an A.I.R. pump. In the last year or two, it has been revised to say ALL 1975 Corvettes came with an A.I.R. pump. On all the cars I looked at, it was plain as day on the emission sticker that says "EFE, AIR, EGR, OC EXHAUST". Right there says it all.
Burning Brakes
Joined: Dec 2021
Posts: 805
Likes: 260
...I believe EVERY '75 Corvette came with an A.I.R. pump, but many have argued that they have low mileage original cars and their's never came with one blah, blah, blah. 1975 & 1976 Corvettes were the easiest to make look like it never had a smog pump as it DID NOT have the typical A.I.R. exhaust manifold "trees". '75 & '76 had a single rubber hose coming off of the smog pump to a pipe connection just below the heat riser. So it was easy to make it look like it never had a smog pump once you removed it. They used exhaust manifolds exactly like a '74 L-48 automatic Federal Emission car which never, ever came with a smog pump so the exhaust manifolds won't have a place where the A.I.R. trees attached to. I've looked at a ton of 1975 Corvettes and if it wasn't all "redone or modified" and mostly original or survivorish, I could tell there once was an A.I.R. pump on it. The NCRS Guidelines "used" to say that "maybe" some did not come with an A.I.R. pump. In the last year or two, it has been revised to say ALL 1975 Corvettes came with an A.I.R. pump. On all the cars I looked at, it was plain as day on the emission sticker that says "EFE, AIR, EGR, OC EXHAUST". Right there says it all.
