Catalytic converter?

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While changing the wheel bearings this past weekend on my 76 NYB, I took a look underneath to see if there were any issues that need addressing.
It appears, there is what seems to be a catalytic converter in my exhaust system.
I was under the impression that they were not CAT vehicles in 76.
Could I be mistaking a resonator for a CAT?
The exhaust system was replaced prior to my ownership and appears near new except for the very front where it clamps to the manifolds.
If it is a CAT would it affect the performance of car negatively?
 
Edit: no misinformation.

The original resonator would be installed just after the rear axle.

I can't tell about the possible difference in performance.
 
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If it is a CAT would it affect the performance of car negatively?

I would think an old/original cat would be pretty restrictive. A more modern one, not so much, very similar to a muffler. But remember, you're dealing with a cruiser, not a race car, so you probably wouldn't notice much by removing it. Maybe a little increase in MPG.
 
I would think an old/original cat would be pretty restrictive. A more modern one, not so much, very similar to a muffler. But remember, you're dealing with a cruiser, not a race car, so you probably wouldn't notice much by removing it. Maybe a little increase in MPG.

I agree as long as the cat is is not plugged there probably will not be much difference in performance. You would need to check with your local regulations to see if you can remove it without possibly getting a big fine if the vehicle is subject to emission inspection. The catalytic convertors are usually dead after about ten years or 100k, so depending on the age of the unit it might not be doing anything anyway. These cars would usually run better if the EGR valve was blocked off as the valves were famous for getting clogged with carbon and sticking resulting in poor performance.

Dave
 
Catalytic converters were not mandated in 1975, but most manufacturers used them to meet emission standards that ramped down sharply in 1975. Emission standards were always set in terms of technology forcing standards, but never did they prescribe how you had to meet them.

Chrysler thought they were going to be able to avoid catalysts by using the Lean Burn System on their cars, but instead they ended up having to employ both to pass the standards and also had driveability problems galore due to their junk lean burn system. Chrysler couldn't figure out how to utilize a catalytic converter until around 1978 to cut emissions and then started to drop lean burn as a result. But they still couldn't avoid bankruptcy in the 1980 timeframe due to the terrible driveability of their lean burn systems and fed up customers plus their efforts to cheapen their cars overall to save costs.

I was unfortunate enough to be working for them to watch all this take place. The inertia of management in those days was pathetic. And the sole factor almost in deterining a promotion was how much a manager decreased costs from year to year. Unfortunately, when a new manager took over and the crap hit the fan, by then the guy that got promoted was calling the bigger shots.

Lee Iacocca was badly needed after the bankruptcy to turn things around.
 
I will concur that standards tended to drive the technology back then. No specification of how to meet them, just "meet them".

Everybody tended to go to catalysts (i.e., after0-treatment) to get the affected vehicles into compliance.

The tech at the local dealership showed me a graphic of where "heat" was/would be under the hood of a cat-equipped vehicle. Quite a bit, according to that graphic!

What I also understood was that catalytic converter-equipped vehicles were banned from many federal lands due to the heat of the exhaust system possibly causing fires from grass contact with the hot exhaust system. Whether this was from "fear" or "fact", I'm not sure as cat-equipped vehicles were purchased several years later, by the affected federal agencies, it seemed. The Chrysler exhaust systems had an environmental heat shield that hung below the converter itself, as my '80 Newport had. The bottom of the GM-pellet converters had a layer of heat-reducing material in the bottom of their case, which probably served the same function, by observation.

Chrysler did have THREE engines in '75 and '76 that had no converters, from the factory. The 318 2bbl, 360HO, and 400HO. What might be termed "fleet engines" which would be installed into A/B/C-type platforms for law enforcement vehicles, typically. I don't believe they were certified for CA or High Altitude registrations, though, just normal "Federal" emissions areas? These cars, along with the ELB cars, would have a "Non Catalyst" decal on the lh front door, rather than "Catalyst". They were different colors with both having black printing. One was gold and the other one silver?

So, check the VIN for the engine code and also the FSM for the emissions regulations for the particular vehicle. PLUS the emissions compliance decal under the hood. There should be some letter abbreviations on that decal to represent the emission control items on the vehicle.

As for "older vehicles", be sure to check to see what your region checks and considers at the time of vehicle inspection/registrations.

Pictures?

CBODY67
 
If a cat converter is still functioning, there will be the distinctive smell out of the tail pipe. If it's a fresh converter, the smell will be more intense. They were supposed to last past 50K miles, or whenever the factory emissions warranty ended, but most would last longer than that, by observation. Especially after all leaded fuel was banished from the supply chain. At later points in time, CA had a 100K mile emissions warranty mandated for vehicles sold there, as I recall. Interestingly, aftermarket "direct-fit" and other "universal" replacement converters have to only meet a 30K warranty from their manufacturer. Might be due to the amount of catalytic material on the ceramic part?

Restrictive? If you look through one and see the ceramic honeycomb monolith in them, you'll wonder how anything gets through it at all . . . but it does. If there's any greater restriction, it'll probably be near the power peak and not at normal cruising speeds. In general, no big deal. Possibly a bit more "throaty" sound to the existing exhaust.

The size of the coated ceramic is variable, in the aftermarket, sized by engine CID, with a few different exhaust pipe sizes on them. The "sizing for engine size" determines how quickly the converter fires-off upon cold start-up, but having a larger one than needed can possibly have less restriction and still work well once it's at full operating temp.

Using an IR heat gun can quickly determine if what's there is a cat converter or a resonator. Cat Converters will be in the pipe just past the y-pipe (with some "mini-cats" in each side of the y-pipe on some later models, to fire-off quickly for cold-start emissions control). There are marked visual differences between a cat converter and resonator, too.

Enjoy!
CBODY67
 
Aftermarket catalytic converters sold for older cars in California need to be beefed up ones by law, but in my experience in replacing the catalyst in my 1989 Dodge Dakota and going through smog checks every two years, these converters are lucky to last more than two years in use. They are much more lightly loaded with precious metals than the originals, so this replacement industry seems to be doing some scamming at best. Original ones lasted at least 10 years of normal driving as long as no misfires were present that would take them out or other problems with the fuel system and/or air pumps on cars so equipped.

I am going to ask my contacts at the California Air Resources Board if they have looked into this poor performance of so-called "OBDII compliant" catalytic converters. Maybe an investigation is needed to clean things up.
 
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