Catalytic converters

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1975. I’ve parted out a few A body cars. The ‘75 models first got the converters and a different floorpan with a bulge to allow clearance around it.

I was hoping for experience with the cars; from what I've seen, SOME car engines got cats in 75, but not all. I'm just not sure which ones.

Here's some information from the dealership data book '75. According to the data book a "catalytic converter...is standard on most models".

Screen Shot 2022-05-12 at 10.23.10 AM.png
https://www.hamtramck-historical.com/images/dealerships/DealershipDataBook/1975/75-Dart_0002.jpg

So looks like '75 is the right answer, for "most" of the '75 models anyway.

In California it used to be a rolling 25 year deal, anything more than 25 years old was exempt. Then they stopped it so that '75 was the last year exempt. I had always thought it stopped there because '76 was when the convertors came out, so you couldn't take a catalytic convertor off a car that came equipped with one. But it looks like I was mistaken! Thanks for the correction @Kern Dog

We dealt with an EPA audit for a 2 year period while they dissected all of our exhaust products. We paid the nations top emissions lawyers a lot of money to help us during this time. Not to sound like a complete JA but what experience do you have with the EPA with respect to emissions?

As a California resident and owner of a '74 model year car with an engine swap that is completely smog exempt, I can assure you that no catalytic converter has to be added to a '73 or later car here. '75 and older are smog exempt in California and do not need to be tested, let alone have anything added.