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Adding a cat to a car that never had one.


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My '78 Wagon came from the factory, with no Catlytic Converter. Im in the process of restoring it, and one of the largest hurdles is the California emissions standards. Im affraid it might not pass.

 

If I replace the exhaust and have them put in a generic catalytic converter... will that help to reduce emissions? Or would it be best to just have a new exhuast made without one?

 

-Brian

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My understanding is that if it meets the emissions standards at the time of manufacture, you're good to go.

 

Make sure you have this data when they do their E-check, so you can challenge them if they try to pull some sh*t on you. If you are lucky, the sticker will still be on the underside of your hood. If not, you can get a replacement sticker thru Subaru of America.

 

Any kind of mods will get you in trouble. Just stick to the original configuration and you'll be fine. Do a thorough "maintenance tune up" before you go in to make sure you are running clean. I'm talking about things like PCV, charcoal, breather filters etc.

 

good luck, John

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I know up here in WA... cars after a certain age aren't required to take emmisions tests anymore. 2 years ago, when I bought my '76 chevy truck, I thought I had to get it to pass emissions. Went, did the test... it did pass, but that really didn't matter, because I didn't have to to get it tabbed.

 

Not sure if California has a similar system... but it would be worth it to check out.

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The cut-off year for california smog is a little bit older. Being you dont have to smog it if its '75 or older. Part of it depends on who you take it to, to get it smogged. Last time I had mine smogged it had the glasspack on it, and they didnt seem to care, nor they didnt seem to care that I had removed the air conditioning belt. However the first time I got it smogged elsewhere they made me install a coolant overflow tank, even though the car never came with one out of the factory.

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Brian I have a CA smog license. If you need some advice specific to our CA emissions testing let me know.

 

And to answer your actual question. YES. adding a cat will help. There are a lot of other thing involved but if the car was a boarderline fail a cat would help.

 

Nvzeno is correct about getting a pretest. its a good idea.

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Yeah, i already plan on giving it a tuneup and having it pre-tested. believe me, the engine needs ALOT of work to get it cleaned up, and i know for sure right now it will not pass. But i got new PCV stuff for it, and will end up replacing the cap, rotor, coil, plugs and wires before its tested. Im also going to need to get the exhaust replaced, or patched.

 

The door does have the sticker, so proof isnt going to be hard.

 

I just figured, since it needs exhaust work anyhow, maybe it wouldn't be a bad idea to have a Cat put in, just to be on the safe side.

 

We'll get it tested 1st, then see what happens.

 

-Brian

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I havent even started to work on the car. Its run twice since i brought it home, once to move it out of the garage, and once to move it back in. At the moment, im working on getting my '84 to pass smog. That needs an entire exhaust, if not more work. After thats said and done, i'll start working on the '78.

 

Right now, there is so much oil everywhere, i cant tell which is new, and which is old. I will take the car to the carwash and degrease the engine then start to work on it.

 

-Brian

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Brian -- Catalyzed engines are tuned to run a little bit "dirty" so that the cat has something there to work with, putting one on your car would be $50 or so that you could spend on tuneup parts to make it pass without the cat. If you know someone who has an exhaust analyzer, have them analyze it, that will tell you what it might need..

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Catalyzed engines are tuned to run a little bit "dirty" so that the cat has something there to work with

 

you might want to clarify this a bit. they don't run "dirty"

 

what I think you were tring to explain was the cycling of the O2 and its relation to the cat. they bounce back and forth between lean and rich verry quickly to make the cat work most efficietly yes. this is why if you look at data or a signal of a good hot O2 it will cycle up and down.

 

if you just fed the cat a rich mixture all the time you eventually will get a dead cat.

 

sorry to get all crazy but I take diagnossis to heart and want others to understand whats up.

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  • 2 years later...
...

sorry to get all crazy but I take diagnossis to heart and want others to understand whats up.

 

Bravo!

 

Hey, pm me if you have thoughts about adding a cat to a dinosaur (grin). My 1969 Dodge A-100 camper van, V-8, of course never had a cat. But on that engine, oil leaks past the loose rings whenever it sits more than a week). The blast of black carbon as it burns up that oil is ... well, this was made the year Armstrong and Aldrin landed on the Moon. It's no smokier than a Saturn V launch.

 

I'd be happy to add a cat to it, even though I don't drive it 400 miles a year, just to be a good neighbor (and not have to wait til the neighbors leave to start it up).

 

If not, I guess it's a garage-type exhaust hose leading into a big box made o' furnace filters to catch the worst of it.

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it'll have to pass emission standards for the year of manufacture, and since cats require fairly precise control of the amount of oxygen in the exhaust to function properly, chances are putting one in won't do any good. Tune it up as best you can, might have to tinker with mixture, etc.. but just make sure you take in in there with new filters, and a fresh tune up and you should be fine.

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