blackbirdpilot

My 1969 350/350hp 4spd no longer has the factory exhaust manifolds. I can't tell if the car orginaly came with Smog equipemt. How can I tell for sure? Dont see any brackets, lines, gulp vlave, pump ect.

:confused:

hunt4cleanair

Quote:

My 1969 350/350hp 4spd no longer has the factory exhaust manifolds. I can't tell if the car orginaly came with Smog equipemt. How can I tell for sure? Dont see any brackets, lines, gulp vlave, pump ect.

If its a 69...It came with an A.I.R. pump. If the emission label is still on the car...well I take that back. In 69 the label did not specify the emission equipment installed on the vehicle.

jerryp58

I've never quite understood this, my '77 AIM shows the engine with and without A.I.R.. Mine doesn't have it and as far as I know, it never did. It has smooth exhaust manifolds (no evidence of A.I.R. holes plugged), it has the correct pulleys, no empty brackets, nothing. Based on all of that, I believe that my car never had it.

mfendley

In 77, the L-82 had an AIR Pump, the L-48 did not.

Tom73

Here is a listing that I compiled from various BBS discussions that may help somewhat.

1966 CA-delivered Corvettes, except for the L-72, used the A.I.R. (RPO K-19) system

1967 CA-delivered Corvettes, used the A.I.R. (RPO K-19) system.

1968 & 1969, ALL Corvettes used the A.I.R. system regardless of engine, transmission, or where delivered.

1970, Chevrolet went to the CCS (Controlled Combustion System) for emissions control on most Corvettes, except the LT-1s which used A.I.R.

1971, Corvettes continued to use CCS (except LT-1s and LS-6s which used A.I.R.).

1972, A.I.R. system returned for most Corvettes except engines except L48s with the "CKW" and "CKX" code.

1973 - 1975, all Corvettes used A.I.R, except for the 1974 L48 with automatic and Federal emissions which used CCS.

1976, all Corvettes returned to CCS, except California-certified cars which used A.I.R.

1977, all Corvettes used CCS, except California and "High Altitude" delivered cars which used A.I.R.

(Not sure on the '76 and '77 Vettes as I thought all L82's used A.I.R.)

1978 & 1979 all Corvettes used CCS, except California cars, "high altitude" and all L-82s which used A.I.R. L-82s were not available in California or "high altitude" areas during these years.

1980 - 1987, all Corvettes used A.I.R.

1988 - on, A.I.R. was used on most, if not all Corvettes, although many C4s use an electric air pump.

tom...




[Modified by Tom73, 7:33 AM 7/28/2003]

Jim Shea

One other fact. The lack of pipe plugs in the cast iron exhaust manifolds does not always mean that a particular engine did not have an AIR system. Some of the AIR pump systems fed air into one large fitting on the passenger side downpipe. I know for sure that my 1975 L82 engine had this system. These engines did not have the little tubular steel manifolds that fed air directly into the cast iron exhaust manifolds near the individual exhaust ports.

Chuck Gongloff

ALL 69's regardless of engine and trans combo's, even the L-88 had the smog pump. NO exceptions. Chuck

hunt4cleanair

Hey Jim:

What emission label code is shown on your L82?

Jim Shea

My emission label is AU.

blackbirdpilot

This is a late '69. First sold in november of 69 and built in Sept of 1969. Would this make it fall under the '70 emisssions standards?

The AIR on all '69's only applys only to Corvette? I've had two '69 Chevells and neither of them had AIR. One was 300hp 350 the other was a 325 hp 396 SS.

hunt4cleanair

Quote:

My emission label is AU.

Thanks...Paul B and I were talking in Hershey and don't believe 75s came with emission lable WK...as indicated in the NCRS Tech manual.

hunt4cleanair

Quote:

This is a late '69. First sold in november of 69 and built in Sept of 1969. Would this make it fall under the '70 emisssions standards?

The AIR on all '69's only applys only to Corvette? I've had two '69 Chevells and neither of them had AIR. One was 300hp 350 the other was a 325 hp 396 SS.

All vehicles sold in the US since 1968 are subject to the federal emission regulations for CO, HC and NOx...in recent years cars are subject to emission particulate regs.

Now, how the manufacturer accomplished that may differ but all must comply. The engines must be certified and pass emission tests to become certified for sale in US markets. I read somewhere that it cost on average $10,000 per powertrain combo to become certified. So, if a manufacturer has an L48 and L82 car with both automaticc and manual transmission...their cost was $40,000. This is why in the early 70's we saw the number of engine options decline rather dramatically...the cost and number to get them certified.

And yes Chevelles were subject to same regs and the probablily is that your 69 chevelles were required to have A.I.R. pumps to come into compliance for the emission standards of CO and HC in 1969. I haven't researched Chevelles but remember it is the engine/powertrain combo that gets certified so if the 350,350 Corvtte engine was required to have AIR to comply, the probability is high a 350/350 Chevelle engine was also required to have AIR to comply. The 396 I'm sure required AIR.

The alternative emission technology was CCS or controlled combustion system was the alternative but was not introduced until 70. These were the primary methods for getting vehicles (GM) certifed...so if the car didn't have A.I.R. as the technology to bring it into compliance...it was configured with CCS or carb, timing calibrations. Here's some stuff I wrote on the subject:

"In 1970, Congress passed the Clean Air Act that would layout emission requirements throughout the C3 generation. This was also the first year equipment was in place to test emissions and therefore tests began to check for hydrocarbon (HC), carbon monoxide (CO) and nitrous oxide (NO2) emissions.

To meet the tightening emission standards but reduce cost, GM began to tinker with a combination of carb and distributor calibrations to lean the fuel mixture while eliminating the need for the A.I.R. system. Typically those early cars equipped with CCS (Controlled Combustion System) were base motors with automatic transmissions and not destined for California. Special Hi-performance cars (LT1 and LS4) were delivered with an A.I.R. system that enhanced performance in contrast to popular convention. So, in the Corvette advertising campaign, readers would see “enhanced performance” which simply meant over the alternative or combined combustion system.

CCS was a performance robber and therefore in the early years of its introduction, limited to base engines, automatic transmissions. Special hi-performance Corvettes were equipped with A.I.R. to maximize performance.

What GM forgot, was that those most interested were the muscle car mindset whose standard of comparison were the pre 1970 high performance vehicles. Even today, hot rodders, muscle cars enthusiasts admit the first item to be yanked from a high performance engine compartment was the smog equipment."

So the probability is that the AIR equipment was removed from your Chevelle motors prior to your trusteeship! Hope this helps.

Paul Borowski

hunt4cleanair---And Jim's car is a 4 spd where mine is an automatic.

Paul Borowski

Jim, this is absolutely correct!!! This is one thing me and hunt4cleanair looked at at Hershey---this is why people are easily fooled on '75 and '76 Corvettes "that ORIGINALLY" had smog to make them look like they NEVER had it. Since they had the non-drilled & tapped exhaust manifolds, all you had to do was remove the pump and hose piping, AIR pump mounting brackets, the 'EXTRA" third pulley which is stacked on top of a double pulley, and it APPEARS the car never had smog------------EXCEPT one tiny detail--------if, IF the car has it's ORIGINAL emission sticker it will say for example, EGR, AIR, OC EXHAUST,EFE. This is the giveaway that the car HAD smog originally :p: :p: :p:

Burgundy 69

"My 1969 350/350hp 4spd no longer has the factory exhaust manifolds. I can't tell if the car orginaly came with Smog equipemt. How can I tell for sure? Dont see any brackets, lines, gulp vlave, pump ect."


Having just recently completed a restoration on my 69 L-46, I can tell you that your car was indeed built with an AIR pump. Unfortunately, your situation sounds exactly like mine. My original 350-350 was removed, along with exhaust manifolds, pump, brackets, etc a long time ago. A replacement 350 with incorrect exhaust manifolds (no provisions for air tubes) was later installed.

After purchasing my car, I decided to restore it to original configuration (or as close as I could get). This meant tracking down a pair of correct exhaust manifolds (with tubes), the AIR pump, pulley, two brackets, diverter valve, hoses, tube check valves and clamps. I was fortunate to find a "correct" functional 69 diverter valve. My understanding is that replacement units do not have the muffler found on originals.

Anyway, depending how you go (new replacement vs original used), all of the componants can be found and installed easily. Good luck!

Mark

Jim Shea

Paul,
Saginaw Steering Gear Division, GMC originally designed and developed the Air Injection Reaction pump for General Motors. Early in the program (middle 60s) it was thought that all engines would have to use the AIR pump in order to meet emission standards. So Saginaw tooled the pump for very high volume. They also developed different displacement, as well as three vane and two vane pumps.

The AIR system is very reliable but also quite expensive because of the pump, diverter valve, and plumbing. As you mentioned, in many cases the automobile manufacturers came up with alternate methods of meeting the standards. What Saginaw found was that the AIR pump business was feast or famine! In other words, some years volumes were extremely high; meanwhile, the car company powertrain engineers were frantically working to eliminate the AIR system as soon as possible (in many cases the very next model year).

So volumes varied considerably year to year. To have very expensive manufacturing equipment standing idle for a year, (waiting for volumes to go back up) resulted in unacceptable profit margins for the AIR pump business. For the above reason, Saginaw got out of the AIR pump business.

BTW, my AU emissions label has the following information:
AIR-EGR-EFE-OC; the sticker has a table for automatics as well as manual transmissions (so it is the same sticker for both); it also says 350 cu in, high performance 4 bbl, GM10K43A.

Jim

Paul Borowski

:yesnod: :yesnod: :yesnod:

RLaFarge

I have a 79 L-82. Should there be an AIR Pump on mine? I am about to put headers on it. I hate to seem stupid, but I won't know until I ask, but what does this smog pump do? If it is missing do I need to put a new one on. There is no emmission testing in Al. yet.

Burgundy 69

The basic idea, as I understand it, is that the pump injects fresh air directly into the exhast gases, causing the exhaust to burn cleaner.

For instance, on my 69, the air goes through the pump to the diverter valve where it is split and sent via hoses to one way check valves (prevents back flow from exhaust system) at the exhaust manifolds. Each manifold has a set of holes (69 has 4) with tubes passing through to the exhaust port on the heads. The fresh air seems to hit the exhaust while inside the heads before the exhaust reaches the manifolds. I'm not sure how this causes the exhaust to burn cleaner. Anyway, that's my take on the AIR system.

Mark

77Dream

My L-48 does.