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post #1 of (permalink) Old 11-17-2002, 12:42 AM
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5.0 swap emissions questions

Hi all, I am smack dab in the middle of my 5.0 EFI swap and have an endless number of questions!

My EFI 5.0 came out of a 1990 Crown Vic, and has a smog pump. I am planning on leaving this off the engine before it enters my CJ, but I am looking for some feedback from those more wise on 5.0 swaps. I have done a ton of research on what exactly the air injection is doing, and how it affects emisions, etc. but I think that by 1986 CARBed standards, this puppy should pass with flying colors regardless! [img]images/graemlins/tongue.gif[/img]

The main reason I am planning on leaving it off is because the sucker is frozen up. It looks like I should be able to leave the exhaust plumbing intact, and simply plug the hose that would have gone into the pump right? I have read that I will get a CEL by leaving this off, and I have heard that I won't, and I've also heard that the CAT will burn up if I leave it off, and quite possibly green peace will place me on their top 10 most wanted list. Now if I get a "universal" CAT, then I shouldn't have to worry about the thing burning up right? Again, looking for advice from those that have been here already [img]images/graemlins/laugh.gif[/img]

Thanks guys!

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post #2 of (permalink) Old 11-17-2002, 04:28 AM
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Re: 5.0 swap emissions questions

As far as I know, all the smog pump does is inject oxygen into your exhaust. I believe it's supposed to help the catalytic convertor do it's job. I'm doing a 5.2L swap right now in California. I read that my Jeep has to pass the visual inspection first before they even hook it up to the sniffer. So basically, if I leave one piece of smog equipment off the swap, it fails, no matter how clean it runs.
post #3 of (permalink) Old 11-17-2002, 04:51 PM
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Re: 5.0 swap emissions questions

It all depends on the emissions requirements in your state. You can leave the pump off and plug the holes in the rear of the heads if you want to. As long as you leave the sensors attached that controlled the pump the computer will not throw any codes.
My '79 is completly exempt here in MA. They don't even look under the hood. Don't know about CO though. You may want to stop by the inspection station and see what the rules are for an 86.
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post #4 of (permalink) Old 11-17-2002, 09:02 PM
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Re: 5.0 swap emissions questions

Well, here in Colorado, the inspections are pretty standard. It's mainly a sniffer test. If anything is glaringly wrong under the hood they might fail you, but it doesn't really seem like they look for anything inparticular. I've smogged a Honda with a JDM Acura engine installed (quite obvious that it didn't come from the factory!) and it was a piece of cake.

Based on the fact that my 86 CJ came with a carb, the limits are probably pretty forgivable, so I HAVE to imagine that a fuel injected EEC controlled engine will pass with flying colors. From what I've found, the smog pump simply injects a small amount of air into the exhaust manifold after combustion to burn any fuel residue left behind, and is mainly used during warm-up or when the engine is not at it's warm up temp. If the EEC is doing it's job and providing close to 14.7 A/F ratio then the smog pump is passive. That makes me feel a lot better!

Now I also found that the three way CAT uses exhaust to propagate the NOX elimination, and if you take the smog pump out of the loop you can burn up the CAT pretty quick. What would be a good "all purpose" CAT to buy? What are you guys with V8 swaps running? Summit has a huge selection of "all purpose" CAT's ranging from 14 inches long to 17 inches, and various inlet outlet sizes. What is a good size to stick with for a V8 application? Thanks!

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