A way to save the cats? (1 Viewer)

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e9999

Gotta get outta here...
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I had to do an emission test the other day on my DD. The conversation with the tech turned to the cats on the 80. I mentioned that the OEM cats were very expensive on the 80 ($1000 or so from memory) whereas the aftermarket ones were much cheaper ($200). I was asking him if he thought I could use aftermarket cats if the OEMs conk out. I also asked if OEM stuff was required for testing or anything that passes the test would do. Didn't get a real answer but he said something to the effect that post OBD2 are much more expensive. Is that true? What's the difference?

Anyway this got me thinking (yea, I know). Since the OEMs are so expensive, do wear out, and may possibly be required for emission testing in Commie states (not sure about the OEM part), would it make sense to take them off, mount suitable aftermarket -if much cheaper and still doing a good job for the environment- and save the OEMs for testing every 2 years?

Yea, I know a bit extreme, but so is spending $2K on OEM cats...
 
Whoo boy...

Consider yourself lucky that you don't live in CA. There are threads about this elsewhere, much was discussed about this as I was re-doing my whole exhaust but here are the answers to your questions.

GENERALLY OBD-II cats are more expensive than pre OBD-II, as they have to be more consistent performing as the computer can accurately monitor emissions and then turn on the check engine light if stuff isn't right along with tighter emissions standards as the years go on.

In many states you can fit an OBD-II compliant aftermarket cats and be fine. In CA this isn't an option. Local laws will tell the story. You will have fewer problems if you install 2 smaller cats to raise fewer questions with the inspector visually.

The other option is rebuilt CATs, probably what I'm looking at next smog check. Check out Kansas City Converters at http://www.kansascityconverters.com/ for more info. I forget the price but it's pretty reasonable.

Personally, it's a pain to replace the headers/cats so I'm waiting till mine no longer pass and then going the KC Converters route. Even though I can't recall the exact price it was A LOT CHEAPER than OEM new!
 
are you positive that you can't have aftermarket cats in California even if the emissions meet the limits?
So the cats are not easy to remove and replace?
 
I know way too much about CA emissions...

You cannot replace CATs with non-OEM on OBD-II equipped vehicles. The problem is not that the law says you can't as it allows it as long as you use an approved aftermarket CAT. There are NO approved CATs for OBD-II equipped vehicles in CA and it has been that way for quite some time. There are a lot of politics involved and it doesn't look set to change what with the governator's repeal of the 30 year rolling exemption last year.

In CA, you're stuck with OEM on OBD-II equipped vehicles. In fact, I couldn't find a shop willing to put aftermarket CATs on my truck (I asked 4 seperate ones) as they could lose their BAR license and be fined up to $10,000. OUCH!

The CATs are NOT easy to R&R as they are a part of the header. You have to remove the header as the cats are attached and that brings up another point...

If you remove your CATs (and header) you'll have to find another header to weld your aftermarket CATs too if you want to keep the OEM for later use. Either that or just cut and weld every two years...

I cut mine CATs out and turned 'em 90 degrees for a TON more clearance and it cost all of $40 or something so you might want to consider it.
 
We already have some of the toughest regulations on AUTOMOBILE emissions in the world. CARB sets the standards the rest of the world follows.

The irony is that our largest polluters, manufacturing etc. have considerably LOWER emission regulations that other nations concerned with the environment...
 
can't you hold the cats in place with clamps?
 
tiorio said:
with the governator's repeal of the 30 year rolling exemption last year.

does this mean that if it's 30 or more years old, it now has to pass emissions?
this really is bad news. i have a fj40 that has been de-smoged and i was going to put it on the road as soon as some other work had been finished on it. looks like it might be an arizona weekend play truck instead.. i'm in cali but very close to the az state line.
 
miked said:
does this mean that if it's 30 or more years old, it now has to pass emissions?
this really is bad news. i have a fj40 that has been de-smoged and i was going to put it on the road as soon as some other work had been finished on it. looks like it might be an arizona weekend play truck instead.. i'm in cali but very close to the az state line.

Yep, that's what it means! 75 and newer will still be subject to smog inspection into the forseeable future. 74 and earlier are permanently safe...
 
e9999 said:
can't you hold the cats in place with clamps?

Well I suppose you could do that if you had your headers and cat-back flanged for that. Then your replacement aftermarket cats would have to be the same dimessions (or have an extension welded on to be the same dimessions) as the OEM...
 
tiorio said:
Yep, that's what it means! 75 and newer will still be subject to smog inspection into the forseeable future. 74 and earlier are permanently safe...
I just checked the CA DMV page -- which linked to www.smogcheck.ca.gov. It indicates there that 1976 and newer are subject to smog checks. 1975 and older are exempt.
The 30-year rolling is indeed gone (for now).

From the site:
"Beginning April 1, 2005, the 30-year rolling exemption will be repealed. Instead, vehicles 1975 model-year and older will be exempt. Therefore, 1976 model-year and newer vehicles will continue to be subject to biennial inspection indefinitely."
 
Doug, you're right of course...

There was a point where it was going to be effective Jan 1st but that was ages ago and I haven't let it go I guess. Lucky 1975 owners!
 
put down the hash pipe e, just run them till they take a crap then get some from discount converter
 
How would they know if you replaced them with aftermarket cat's? Surely the min. wage inspection clerk is not going to be able to spot the difference.

Run your OEM’s until you have a problem, if you want them to last longer keep the motor in good shape, burning oil and off mixtures will shorten their life,
 
RavenTai said:
How would they know if you replaced them with aftermarket cat's? Surely the min. wage inspection clerk is not going to be able to spot the difference.

Run your OEM’s until you have a problem, if you want them to last longer keep the motor in good shape, burning oil and off mixtures will shorten their life,

yes, you could probably count on the tech not noticing the difference, but does one know for sure that aftermarkets would pass the emission tests?
 
Several here have used aftermarket cat's, I think we would have heard if they do not pass emissions. But I guess you need someone with experience with them in the PRK to be sure, here in GA on 96+ if no codes then you pass emissions so it is pretty easy. if my cats ever fail I can use an O2 simulator to get by. I like using OEM parts but at $1K is just to much for a catalytic converter.
 
You CAN use aftermarket CATs in most states outside of CA!

As far as the tech picking out the non-OEM cat...well I've had a lot of personal experience with this. The information they are given by the computer is fairly detailed and they can loose their license if they screw it up. Some of them don't care and you will pass and some of them are uber-anal.

The 'O2 simulator' won't work here. It's a rolling dyno test for 2WD vehicles and a tailpipe sniffer no-load multiple RPM test for AWD vehicles like the Cruiser. The visual inspection is fairly rigorous as is the tailpipe inspection. Hell, they pull the gas cap off and test it too.

Anyway, state laws dictate what you can and can't get away with. CA sucks for emissions testing...
 
What if you use aftermarket cats but cover them up so they are barely vissible with some sliders and a skid plate. It would still pass emissions and it would be too difficult to tell that they are not OEM. Through a little mud in the mixture and I would guess that your average tech would not notice. But then again it would be breaking the law.
 
It's not the breaking the law that I worry about. It's the '**** factor' that comes into the equation if the tech DOES notice. In CA they go after you for breaking the law for tampering with the equipment (unless you can prove you bought it that way) and then they try to go after the shop you (obviously) hired to do the work to break the law.

I had a vehicle where this exact thing happened. In the end, I 'won' but at a horrible time expense and a not insignificant monetary expense. And this was for a 1968 Porsche which was emissions 'exempt'. It all depends on the tech on the machine at the test station and the clerk at the window at the DMV. The magical wrong combination can get you in a whole hell of a lot of hot water while the guy next to you with the 1999 car with the 1978 motor gets by with no problem...
 
Eric-Am I understanding this right? You have perfectly good cats, you passed smog, and you are worried about aftermarket catylitic converters? Run them and be happy. When they die, buy some new ones.

I think you need somemore stuff to worry about. How about paintless dent removal... before you get dents? How about the heartbreak of aluminium oxidation on the aluminium rims? Maybe you need fan belt polishing compound? I forsee a long and sleepless night-just like me. Just yanking your chain Eric, it will be many years before your cats are a real issue.
 

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