Air Injection Reactor
Le Mans Master
Joined: Mar 2004
Posts: 7,455
Likes: 1,482
From: Little Rock AR
A.I.R. is a good thing when it works right. it draws little HP and makes the air we breathe better. You can take the belt off and do a road test to see what the HP difference is - not that you will notice if at all. The other plus is somewhat more room to work on the engine but that might not matter much to some people.
The only potential downside to having one in place is when it does not work right. You can get afterfiring in the exhaust when you let go of the throttle if the valve fails. More noticeable on a manual tranny car but it can have an effect on AT cars as well. If you do not have that problem, you might consider keeping it. New diverters are hard to find and I am not fully convinced that anyone is actualy rebuilding them. I see many high dollar so called "restored" systems with non-original looking diverter valves so I am still skeptical about anyone actualy rebuilding them, but I may be wrong there.
Hope this helps,
-Mark.
The only potential downside to having one in place is when it does not work right. You can get afterfiring in the exhaust when you let go of the throttle if the valve fails. More noticeable on a manual tranny car but it can have an effect on AT cars as well. If you do not have that problem, you might consider keeping it. New diverters are hard to find and I am not fully convinced that anyone is actualy rebuilding them. I see many high dollar so called "restored" systems with non-original looking diverter valves so I am still skeptical about anyone actualy rebuilding them, but I may be wrong there.
Hope this helps,
-Mark.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
There are only two reasons to keep it: 1) if you need it to pass your state emissions inspection requirements..for having the correct emissions equipment on the car and meeting emissions limit requirements; or 2) because you want to keep the car in 'original' equipment. Reasons for removing it: it's ugly, it robs horsepower, if the engine is tuned properly there is little emissions benefit, and it adds weight that you don't need. Make your best judgement.
Melting Slicks
Joined: Mar 2006
Posts: 2,465
Likes: 0
From: Orange Park Fl
There are only two reasons to keep it: 1) if you need it to pass your state emissions inspection requirements..for having the correct emissions equipment on the car and meeting emissions limit requirements; or 2) because you want to keep the car in 'original' equipment. Reasons for removing it: it's ugly, it robs horsepower, if the engine is tuned properly there is little emissions benefit, and it adds weight that you don't need. Make your best judgement.
From what I understand, AIR does not actually cut emissions whatsoever, it was a way for automakers to comply with the letter (vs the spirit) of federal mandates. If it actually helped, they would still be using it, like cats. God bless, Sensei
Burning Brakes
Joined: Dec 2007
Posts: 952
Likes: 0
Thread Starter
Drifting
Joined: Jul 2008
Posts: 1,873
Likes: 27
From: Sonora CA
Interesting answers / opinions...........
I may just remove the belt and see. The car is pretty much stock original and I plan to keep it that way, however I'm not totally against cleaning up the house either. If it does get removed though, will I get blamed if I forget to put it back on? lol
I may just remove the belt and see. The car is pretty much stock original and I plan to keep it that way, however I'm not totally against cleaning up the house either. If it does get removed though, will I get blamed if I forget to put it back on? lol
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Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
The A.I.R. pump merely blows excess air into the exhaust passage in the hope that it will help burn off any excess hydrocarbons. Obviously, if the car is not "running rich", it does not good at all. But, it was a "Band-aid" idea that addressed one potential issue with lowering emissions levels. Catalytic converters were a better attempt [albeit expensive] toward the "burn-off" effort. So, this pump does nothing for the proper operation/performance of your engine...it just helps to lower emissions IF your air/fuel mixture is too 'rich'. Dump it, if you don't need it; or, if you like originality, leave it there. {P.S. I would not just throw the unit away; there are lots of floks who will pay dearly for a complete and correctly dated air pump and hardware.}
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
The Air pump is an ajunct to the cat, it pumps fresh air into the exhaust stream right at the head to keep the exhaust temp as high as possible going into the cat to make the CAT work better (burn hotter).
As stated above the newer cats don't need the extra air, so you could (theoretically) eliminate the pump, run a new cat and still pass emissions testing.
As stated above the newer cats don't need the extra air, so you could (theoretically) eliminate the pump, run a new cat and still pass emissions testing.
Le Mans Master
Joined: Oct 2007
Posts: 7,441
Likes: 964
From: Tennessee/Rhode Island
One more reason to dump the AIR pump besides all the reasons above, when I replaced my exhaust manifolds on my 78 L-82 with McJack's shorty headers, I was shocked at how big and how far the air tubes extended into the head. I have to believe that these ports create some turbulence and disturb the exhaust flow. They are pretty big tubes! I as mentioned above have everything that I took off the car. If I ever have a problem with emissions, I will just add two modern cats to the true duals to pass the emissions test (and have uncut head pipes for later). I wish the aftermarket industry would lobby for any car 20 years old and older be except from the emissions testing since so few cars that old are on the road and fewer still drive any significant miles. These older cars with or without emissions have virtually no impact on the air we breathe. Too few, no miles driven. It's all very silly.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
Emissions testing requirements are on a state-by-state basis, with final approval being made by the Feds. Several states have recinded emissions requirements on "collector/classic" cars. Hagerty (insurance company) has been very instrumental in helping groups lobby and obtain such legislation. Maybe you need to start that 'movement' in your state...
Le Mans Master
Joined: Oct 2007
Posts: 7,441
Likes: 964
From: Tennessee/Rhode Island
Emissions testing requirements are on a state-by-state basis, with final approval being made by the Feds. Several states have recinded emissions requirements on "collector/classic" cars. Hagerty (insurance company) has been very instrumental in helping groups lobby and obtain such legislation. Maybe you need to start that 'movement' in your state...
Last edited by jb78L-82; Sep 14, 2008 at 09:46 PM.
Thread Starter
Drifting
Joined: Jul 2008
Posts: 1,873
Likes: 27
From: Sonora CA
Sixfooter, that was a very interesting tid-bit of information about the high exhaust temperatures. Maybe that explains the excessive (and what I thought was unsual) amount of heat that was raditating from the manifolds at idle.
So, to recap, I guess that the A.I.R. looked good on paper and probably a good idea at the time. Thanks for all the help.
So, to recap, I guess that the A.I.R. looked good on paper and probably a good idea at the time. Thanks for all the help.
Melting Slicks
Joined: Mar 2006
Posts: 2,465
Likes: 0
From: Orange Park Fl
I don't know, but this is the explanation I heard: The gov required emissions to be reduced to X parts per million (PPM) at thye tail pipe by Y date. Blowing clean air into the exhaust, while not reducing the volume of pollutants, does reduce the PPM. Problem solved.
Melting Slicks
Joined: Nov 2003
Posts: 2,668
Likes: 118
From: St. Charles Mo
CI 5 & 8 Veteran
Danny, As I am sure you already know, They put A.I.R pumps on some of the older cars, before CATS ever existed. My 70 LT-1 and the 69 427 390 hp had one, with no CAT. Then it was just to burn excess hydrocarbons.
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
Thread Starter
Drifting
Joined: Jul 2008
Posts: 1,873
Likes: 27
From: Sonora CA
If I disconnect either hose ( from the pump) that runs to the manifolds and put my thumb over the end of that hose, I can definately feel puffs (exhaust) of air comming out of the hose with the engine idling. does this mean that the check valve is failing? or is this just characteristic of the check valve.
Sorry, this is my first Corvette and I feel like I should be sitting in a cornner with a pointed hat on. ( and I have not received my service manual yet )
Sorry, this is my first Corvette and I feel like I should be sitting in a cornner with a pointed hat on. ( and I have not received my service manual yet )