Air injection pipes?

[mike561]

Would there be any reason why someone would cut all 8 of the air injection pipes on the engine??? i know its just an emmissions feature, and we dont have emmissions testing here in florida but im sure it would save on gas if they were put back on right?. how is all of that routed too and what would i be looking at in expenses to have the pipes put back on? on another note, i was told i could just get some type of "caps" to just cover the holes where the cut pipes are screwed into. any info would be great.... (i really need to get one of those haynes repair manuals too )

['97ventureowner]

I seen a lot of cars back in the '80s where someone cut the tubes, probably thinking that it would make the engine run better. There was a lot of misinformation back then and I knew a lot of people who automatically removed emission/smog equipment with the impression it was a " good thing to do" for your engine and to gain performance. Some people probably cut them rather than fix or replace them if one or more should have rusted or broke off. I remember a set of headers I had on my SBC that had the holes for the air tubes and I believe there was a bag of plugs included if you didn't need to hook up the air tubes. The plugs were threaded and had a square head. You might be able to find the right sized plugs at your local hardware store/home center if you elect to plug the holes.

[mike561]

yeah i was just thinking of getting those plugs, is there a certian name for them or should i just bring the size with me of the broken ones and look for what would work?

[silicon212]

3/8" NPT pipe plugs.

[mike561]

Alright thanks ill check those out. is not having these pipes going to effect gas mileage or will it not matter if i get the plugs also???

[Blue Bowtie]

If this is regarding your '83, there will not be much difference in fuel mileage at all. The A.I.R. system will help get the cat converter hotter faster, and also will help get the O² up to temperature a little faster. Getting the O² active sooner can help mileage a bit when the engine is cold by achieving closed loop as soon as possible. However, once the engine is warmed, there will be absolutely no difference in mileage.

IIRC, most of the manifolds I've seen are closer to a 1/8" pipe plug, and some may be closer to 1/4". The correct plugs are straight thread, not a tapered pipe plug, but if you are abandoning the system, all you really need is something that creates a positive seal. Any air leakage into the exhaust will artificially add oxygen to the exhaust gasses and cause the O² to indicate a leaner mixture. That WILL cost you mileage.

Most modern engines don't even have an AIR pump any more, but have more effective cats and heated O² sensors instead.

If you are concerned about getting maximum mileage, keep the tires inflated, the wheels aligned, the brakes adjusted, make sure the coolant runs close to 200-210ºF, keep your EVAP system in good working order (free gas!), use synthetic lubricants, keep the air filter clean and intake ducts intact to admit the coldest air possible, and maintain a good state of tune.

[PeteA216]

Without the air hoses, when in closed loop, it may VERY VERY slightly help gas mileage by not having the A.I.R. pump on the belt system... just one less accessory to take energy away from the engine. But like I said, it's incredibly slight and most likely won't be noticed.

P.S. You might get about 2 more inch pounds of torque as well.

['97ventureowner]

Originally Posted by Blue Bowtie

If you are concerned about getting maximum mileage, keep the tires inflated, the wheels aligned, the brakes adjusted, make sure the coolant runs close to 200-210ºF, keep your EVAP system in good working order (free gas!), use synthetic lubricants, keep the air filter clean and intake ducts intact to admit the coldest air possible, and maintain a good state of tune.

You forgot one thing:" Keep your right foot out of the carburetor." We used to say that years ago whenever a customer asked us how to get better mileage . Of course nowadays we could say something like "Get rid of the 'leadfoot' " Remember when they use to say to pretend there was a egg underneath the gas pedal and you were supposed to gently step on the accelerator so as not to break the egg when you take off?

[DANZIGS]

I've got a question regarding the clip A.I.R. pipes. Can you hear exhaust leaks coming from the clipped ends or smell fumes? The reason I'm asking is I was thinking about getting rid of mine just for cosmetics.

[PeteA216]

If you're gonna get rid of yours, get the plugs. If you don't get the plugs then when you clip the ends, take a pair of vise grips and crimp the clipped ends to seal them shut. They're pretty thick, you may need to hacksaw them off instead of clipping them.

[mike561]

So i think ill just go with the caps then. i see when they cut the pipes they bent the tips shut as well, but im not sure how good of a seal off that is. ill check out some hardware places though for the caps.

[bobss396]

I'm starting to think that I'm the only one around with a '84 Caprice with an intact emissions system. I did replace the AIR manifold on one side, the bitchy side to change of course.

I cut them as short as possible with bolt cutters, then one by one, heated them with a torch until they glowed red and un-bolted them with a 6-point socket, worked great in fact. The replacement went in with little problem, I used never seize on the threads.

Bob

[Blue Bowtie]

Originally Posted by bobss396

...I used never seize on the threads.

There is the sign of one intelligent, forward-thinking, and technically savvy guy.

I use Never-Seez on nearly everything I assemble unless it's a bolt or thread requiring sealant. . My wife accuses me of sneaking it into my maple syrup so it makes the pancakes glitter.

[PeteA216]

Never seize has gotta be the greatest, yet most simplistic concept around. The second you gotta take that bolt off again it makes that extra 3 seconds you took before to never seize the threads completely worth while. The thing I found the best to use it on is the surface of the rear drums were the rim rests. many a time have I had to deal with rims that have rusted right to the drum and the drum rusted to the hub.

[bobss396]

Thanks gents, I use it for almost anything. I like it in the tube, that way the rest of it doesn't get crudded up like the brush & bottle does.

Anything with the front end gets it, pressed in bushings, tierods, sway bar links. It even works on exhaust parts, it dries out and will come off as dust when I take down a y-pipe. Which I use stainless nuts with.

I do that around the rear axle flange too, had to fight with too many drums in my day. I always use a minute amount on wheel studs.

Bob