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  #1  
Old 12-20-2005, 04:07 PM
GWJoe GWJoe is offline
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i have read a few posts here where people have removed air tubes and "plugged the holes". I have a two part question.

1. exactly how is this done? I assume one removes all the way back to the exhaust manifold, then plug with what?

2. where I am now and where I plan to be in the future do not have emission laws but I don't want to dump a bunch of crap into the atmosphere that I don't need to. So, if I remove the air tubes, can I then use a cat. convertor that doesn't use air tubes? is this even effective?

3. Okay, so it is three part: so if I can remove and plug the air tube holes and can use a cat without air tubes if and when I add EFI, will it work without the smog stuff (I would still have the EGR valve and I think that is needed for the EFI, but not sure)

thanks in advance

Joe
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  #2  
Old 12-20-2005, 04:33 PM
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amc75matador amc75matador is offline
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Everything should work without the tubes. As far as plugging them, if they aren't rotted by the manifold you ca cut them about 3/8 inch above the fitting and fold them over once or twice and bash them with a hammer. If you have a welder, mig is best, just plug the holes on the fittings shut, you can also find small bolts or metal rods to fit in the holes tightly and hammer them in, or you can remove the fittings and the hollow bolts and use pipe plugs in the manifold holes, but I've never been successful at this last method without heating the manifold cherry red with oxy/acetylene and using an impact gun on the bolt. They tend to break right off at the crosshole.
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  #3  
Old 12-20-2005, 04:36 PM
GWJoe GWJoe is offline
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thanks AMC, what about the cat question? would running a non air tube cat on the exhaust help to reduce emissions?, not that I'm tested but i don't want to dump more junk into the air than I have to.
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  #4  
Old 12-20-2005, 05:18 PM
illegalFSJ illegalFSJ is offline
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On my manifolds, I removed the AIR tubes and bolts, went down to ACE hardware and bought 7 bolts that had the same diameter and thread pitch as the bolts that held the tubes on. Then, spin them in with an impact gun, and cut them off flush with a cut-off wheel on a die-grinder. Gives it a nice, clean look. Much easier with the manifold removed from the vehicle.
YES: the cat is still effective at cleaning up your emissions.

[ December 20, 2005, 11:19 PM: Message edited by: illegalFSJ ]
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  #5  
Old 12-21-2005, 12:41 AM
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Ted_Z Ted_Z is offline
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As for EFI, if you are running closed loop (with an O2 sensor) you need to REMOVE the air tubes. The extra air that gets pumped into the exhaust screws with the reading.
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  #6  
Old 12-21-2005, 01:25 PM
GWJoe GWJoe is offline
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so if I remove the air tubes and remove the smog pump and the air control valve, do I need to do anything with the EGR valve? Does it stay? If not, how do I block off the hole in the manifold that the EGR occupies?

Thanks for answering my dumb questions on this topic.

Joe
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  #7  
Old 12-21-2005, 01:32 PM
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Chevelleguy Chevelleguy is offline
 
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EGR stays. I welded the manifold holes shut with a MIG and ground it flat. Nice and clean. Everyone has given you good info and Ted Z beat me to the 'no air pump with O2' answer.

[ December 21, 2005, 07:33 PM: Message edited by: Chevelleguy ]
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  #8  
Old 12-21-2005, 01:56 PM
GWJoe GWJoe is offline
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I might be able to answer this myself once I look at it more closely, but I am thinking there is a hose going from the air diverter valve into the EGR. Am I wrong on this? Even if it doesn't go to the EGR, I know one goes somewhere, what do I do at the point of where that hose used to attach? Is it another plug of some type?

Thanks again,

Joe
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  #9  
Old 12-22-2005, 05:30 AM
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710 Burner 710 Burner is offline
 
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There is a vacuum diagram on here somewhere that is pretty acurate for your waggy. I'm thinkin' the air diverter and the EGR are tied to the same ported vacuum switch.
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  #10  
Old 12-26-2005, 09:11 AM
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Kwikrat Kwikrat is offline
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Does anyone happen to know what size the bolts are that we can use to block off the a.i.r. holes in the exhaust manifolds?
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  #11  
Old 12-26-2005, 10:14 AM
mark32725 mark32725 is offline
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I did mine like illegalfsj, with bolts can't remember the size though...take one of the air tube bolts to the store with you and match it up....
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  #12  
Old 12-26-2005, 11:50 AM
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Serious Johnson Serious Johnson is offline
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Quote:
Originally posted by Kwikrat:
Does anyone happen to know what size the bolts are that we can use to block off the a.i.r. holes in the exhaust manifolds?
My '83 used 9/16"-18, but I understand that it varied by year.

S.J.
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  #13  
Old 12-27-2005, 12:10 AM
trequad trequad is offline
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I used these http://www.fastenal.com/web/products...l.ex?sku=18939
picture on site is not correct, but trust me they fit. I just snugged em down and haven't had a leak yet.
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  #14  
Old 12-27-2005, 12:15 AM
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drlocke drlocke is offline
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I pulled the AIR system out of my '68. The AIR pump was seized anyway, and was taken off belt by the PO. The holes for the tubing fittings are plugged with pipe plugs of appropriate size.

If you go with closed loop EFI, and employ TFI or HEI ignition, and keep a good maintenance schedule, you will be dumping as little in the way of nasties into the air as is possible with such a large engine.

[ December 27, 2005, 06:16 AM: Message edited by: drlocke ]
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