How bad for the environment is a car without a catalytic converter?
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How bad for the environment is a car without a catalytic converter? I put an LS1 in a 24 year old car, which I hope to drive daily through the summers. Next year, the car will be 25 years old, and I beileve it will be exempt from emissions in my state.
I am ordering parts to build the exhaust system, and now realize that in 11 months I don't think I will be required to run catalytic converters, or any emissions equipment at all.
So my question is, how bad is it for the environment to run a car without catalytic converters? I have heard cats reduce smog, but on the flip side, throw off chemicals that supposedly rapidly speed up global warming.
Should I run cats or not?
-Dave
I am ordering parts to build the exhaust system, and now realize that in 11 months I don't think I will be required to run catalytic converters, or any emissions equipment at all.
So my question is, how bad is it for the environment to run a car without catalytic converters? I have heard cats reduce smog, but on the flip side, throw off chemicals that supposedly rapidly speed up global warming.
Should I run cats or not?
-Dave
Staging Lane
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Cats can reduce the emissions by about 99% when all warmed up. So, without them, you're polluting roughly the same as 100 cars, or more, since it's a big engine.
The pollutants aren't so much greenhouse gases as they are smog gases. If you live out in the country, and park outside, and never spend time in traffic, it's no biggie. But, daily driving, in cities, in traffic (it's not just you that gets to smell the power), I'd highly recommend keeping the cats and charcoal canister working - those two are the huge pollution reducing devices.
Also, if a cop pulls you over for hot footing it, he can still ticket you and probably can impound your car for removing an emissions device, and it's an easy check for him to see.
The pollutants aren't so much greenhouse gases as they are smog gases. If you live out in the country, and park outside, and never spend time in traffic, it's no biggie. But, daily driving, in cities, in traffic (it's not just you that gets to smell the power), I'd highly recommend keeping the cats and charcoal canister working - those two are the huge pollution reducing devices.
Also, if a cop pulls you over for hot footing it, he can still ticket you and probably can impound your car for removing an emissions device, and it's an easy check for him to see.
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Thanks for the replies, I think I am going to use cats and the charcoal canister, but ditch the AIR/smog pump system. I am not too worried about the small loss in HP, and prefer the smell of a car with cats. I will try to put the cats close to the manifolds to help them light off more quickly.
In VA, I will be exempt from emissions testing for registration purposes, however the enforcement officer from the Department of Environmental Quality told me that they set up tests with some sort of sniffer on exhaust ramps that gets readings as cars drive by. If you are a "gross poluter" and your car was built after 1968, they will bust you.
I have heard arguments on smog vs. greenhouse gasses with and without converters, and just wanted to see how everyone weighed in.
Thanks for the help!
In VA, I will be exempt from emissions testing for registration purposes, however the enforcement officer from the Department of Environmental Quality told me that they set up tests with some sort of sniffer on exhaust ramps that gets readings as cars drive by. If you are a "gross poluter" and your car was built after 1968, they will bust you.
I have heard arguments on smog vs. greenhouse gasses with and without converters, and just wanted to see how everyone weighed in.
Thanks for the help!
that's why you should gut the cats and stick a straight pipe threw them, so it will still look like you have them.
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Yeah, its pretty bad. My old car put out 10 times the legal limit worth of emissions without a cat.
On the up side, no one could tail gate me because they're eyes would start burning if they got within 4 car lengths of me.
On the down side, I smelt like raw fuel after driving anywhere in it.
You win some, you lose some.
On the up side, no one could tail gate me because they're eyes would start burning if they got within 4 car lengths of me.
On the down side, I smelt like raw fuel after driving anywhere in it.
You win some, you lose some.
Just run some race ruel in the car with the cats for a tank or 2, and they'll blow themselves right out for you 
Mine came apart after about 500 miles with 105 unleaded race fuel, leaded will do it even faster.
I wouldn't waste your time with any of that emmissions crap to be honest, if you're slugging an ls1 into an older car, as long as you have some mufflers on it that are quiet enough so you don't get a ton of attenion drawn to ya, you won't have any problems.
CT once a car is 25 years old they are exempt from emmissions testing, I don't know a sole with anything that's got any power that is running the cats on it that doesn't have to.
Tune that car in open loop, don't mess with the o2's at all, that whole canister thing, screw that too really. If you do a fuel system that's got a return on it, just vent the tank and call it a day.
The emmissions that are killing the enviornment aren't coming from the less then 1% of cars without legal emmissions equipment, it's coming from the smoke stacks on factories all over china and other places with no regulations.
Mine came apart after about 500 miles with 105 unleaded race fuel, leaded will do it even faster.
I wouldn't waste your time with any of that emmissions crap to be honest, if you're slugging an ls1 into an older car, as long as you have some mufflers on it that are quiet enough so you don't get a ton of attenion drawn to ya, you won't have any problems.
CT once a car is 25 years old they are exempt from emmissions testing, I don't know a sole with anything that's got any power that is running the cats on it that doesn't have to.
Tune that car in open loop, don't mess with the o2's at all, that whole canister thing, screw that too really. If you do a fuel system that's got a return on it, just vent the tank and call it a day.
The emmissions that are killing the enviornment aren't coming from the less then 1% of cars without legal emmissions equipment, it's coming from the smoke stacks on factories all over china and other places with no regulations.
no cats
if your so worried about the enviornment go vegetarian!
seriously new studies have proved that if we all went veg. the methan produced my pigs/cows is like something atrousously more harmful then all the cars/trucks/planes/buses ectt of the entire world combined!
me im no cats and a meatasaurus
if your so worried about the enviornment go vegetarian!
seriously new studies have proved that if we all went veg. the methan produced my pigs/cows is like something atrousously more harmful then all the cars/trucks/planes/buses ectt of the entire world combined!
me im no cats and a meatasaurus
Catless as well here. And my eyes dont water and there is no rotten egg smell. It smells like burnt fuel exiting a car. I have true duals with turndowns before the axle and daily drive 90 miles a day in traffic in the chicago area.
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I don't see myself going vegetarian anytime soon. I always thought "PETA" (see www.peta.org) should stand for People Eating Tasty Animals.
The car is only 25 years old and I want to drive it regularly in the summer. I'll pass on the cat-free smell and sound. I think having no cats would be a novelty and wear off after a few weeks of sitting in traffic to and from work on the DC beltway. Just my opinion.
If the performance loss with a decent set of cats is negligible, I'll stick with the cats. I'd rather give up 5hp than the creature comforts of a cat-free vehicle.
BTW, I have to figure out how the whole charcoal canister thing works. I honestly don't know what it's for or how it hooks up - only that my car has one.
The car is only 25 years old and I want to drive it regularly in the summer. I'll pass on the cat-free smell and sound. I think having no cats would be a novelty and wear off after a few weeks of sitting in traffic to and from work on the DC beltway. Just my opinion.
If the performance loss with a decent set of cats is negligible, I'll stick with the cats. I'd rather give up 5hp than the creature comforts of a cat-free vehicle.
BTW, I have to figure out how the whole charcoal canister thing works. I honestly don't know what it's for or how it hooks up - only that my car has one.
Are you planning on getting it registered as an antique? If you're in VA, once the car is 25 years old you have the option to register it as an antique. If that's what you want to do you only have to get it inspected once for antique tags. After that you can do anything you want emissions wise, but since you're car came with emissions crap it'll need it for that antique inspection.
I ran catless for a few months, didn't once smell gas
but it was loud as a **** (longtubes and loudmouth).
As far as how bad for the environment is a car without a catalytic converter? Imagine tossing a bottle cap into a landfill, it's got about the same impact, none.
With the gas a 747 jet burns in one hour, you can drive your car to drive around the widest part of the Earth about 3.5 times. And that's leaded fuel getting released 30,000+ feet up in the atmosphere. So don't sweat the environment by going catless.
I ran catless for a few months, didn't once smell gas
but it was loud as a **** (longtubes and loudmouth).As far as how bad for the environment is a car without a catalytic converter? Imagine tossing a bottle cap into a landfill, it's got about the same impact, none.
With the gas a 747 jet burns in one hour, you can drive your car to drive around the widest part of the Earth about 3.5 times. And that's leaded fuel getting released 30,000+ feet up in the atmosphere. So don't sweat the environment by going catless.
if you have FI and you have a cat, your gains would be in the 30hp range if you cut that **** off. and then you can sell your cat and get 100buck for it my old grand prix gtp felt so much stronger without a cat.
my old grand prix gtp felt so much stronger without a cat. 
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Just to poke fun - Yeah, a 747 running on leaded avgas, good one. Or maybe they're packing radials in the jet enclosures, and have been fooling us all along. They run on Jet A and B, basically kerosene.
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I don't think I will get antique tags... too many restrictions on the plates in VA. I might as well pay the full registration and drive it whenever, wherever I want. Regardless, there will be no emissions inspection. Only a saftey inspection (brakes, bearings, tires, lights, etc) which does not cover any of the emissions system whatsoever. The only thing that can hang you up is if your car smokes. That will fail your safety inspection.
If you're running stock cats, I bet there is a lot of restriction. I expect less restriction from some steel substrate magnaflow cats.
Another thing to consider - maybe I won't mind the smell of exhaust with no cats, but if it bothers my wife, I'm screwed... or not screwed...
you know what I mean.
Those 747s must be running some of that leaded kerosene!
If you're running stock cats, I bet there is a lot of restriction. I expect less restriction from some steel substrate magnaflow cats.
Another thing to consider - maybe I won't mind the smell of exhaust with no cats, but if it bothers my wife, I'm screwed... or not screwed...
you know what I mean.Those 747s must be running some of that leaded kerosene!