> A lot of Americans take their cat off on purpose for louder noises.
Some people remove catalytic converters when they install a performance exhaust. Nobody is doing it for louder noises because the muffler portion is what dampens the sound.
Also I wouldn’t say it’s “a lot of Americans”. We have emissions inspections in most major cities and your car won’t pass if you remove the catalytic converter. They can now detect modified ECUs, too. Someone would have to be so determined to do this that they’d swap the exhaust in and out every time they had to do emissions inspections.
Yeah, it's definitely a small percent of people. But i do wonder how many there really has to be to have an outsized effect. One of those lifted kid killers blowing black smoke for the entire duration of the bicycle pack is definitely more than 3 of my tiny honda civics, i wonder how many it really is, and how much those modifications increase the "resting emissions rate"even when not blowing shit. Should be illegal, likely is.
I'd wager it's largely disruptive and dangerous in a highly localized way due to the small percentage of folks doing it. Doesn't make it an acceptable practice though. One person "rolling coal" can temporarily blind 3 or 4 cars back and several across depending on wind conditions, etc.
In terms of NOX it can be a factor of 100. If 1% drive without cats they produce half the NOX emissions. In reality it is probably less since there are other old cars as well that have higher emissions
I live in a progressive state and unfortunately encounter "coal rolling" regularly. I also assume that's the point. Someone has to "own all the libs" as it were
However, I do agree that there aren't enough folks "rolling coal" in aggregate to really move any needles on planet-scale environmental impacts though. Just VERY unpleasant to be caught behind.
They muffle slightly, but removing the cat alone isn’t going to make a big difference with modern high efficiency single cat exhausts.
I’ve seen (heard) the effects first hand. Trust me, people aren’t removing the cat just to make their car annoyingly loud. If they are, they’re going to be disappointed.
If I had to guess, the downvotes were from the “A lot of Americans” claim
> HNs lack of knowledge around cars is sort of frightening.
I actually have a lot of knowledge and experience in the automotive space, including with exhaust systems!
Catalytic converter removal alone doesn’t have a big change exhaust tone. I have seen it first hand, and also with 100-cell and 200-cell race cats as an intermediary step.
Your posts are full of condescending assumptions about Americans and HN’s comments about cars, but you’re ignoring the actual facts others are trying to share.
Some people remove catalytic converters when they install a performance exhaust. Nobody is doing it for louder noises because the muffler portion is what dampens the sound.
Also I wouldn’t say it’s “a lot of Americans”. We have emissions inspections in most major cities and your car won’t pass if you remove the catalytic converter. They can now detect modified ECUs, too. Someone would have to be so determined to do this that they’d swap the exhaust in and out every time they had to do emissions inspections.