Going Cat-less ?s
Safety Car
Joined: Jul 2005
Posts: 3,572
Likes: 9
From: Jackson Tn
St. Jude Donor '06-'07-'08-'09
I hear the responses about the strong smell that these C5's produce when running without cats. I am getting more and more curious about this. I can't imagine how the C5 is much different than any of my older hot rods and muscle cars and they never produced a strong smell.
The only odor my older cars would produce would be that of natural exhaust coming from the tail pipes and only noticable when trainling behind the car or if the car were stationary it was mildly noticable when standing near the rear (or side) of the car.
I've always been able to tune a carb so that it wasn't overly rich and I would only hope that a sequential fuel injected motor would be better then even a tuned Q-Jet.
At the very least, I would hope that my Vette is not leaving so much fuel unburned that it would cause 'me' to stink. I think that if that were the case I'd want to fix that condition before installing cats.
I dunno, I think cats were only created to satisfy the EPA nuts and a well tuned engine should run quite clean without them, sure it wont be pure C02 and H2O coming outta the tail pipes, but certainly not raw fuel.
Lastly, it is good to be concious about the environment, but if I were that worried about it I'd be driving a Prius not a Vette. And it should be shunned to run catless on a C5 when its perfectly acceptable to run catless on an LT-1 '70 Vette.
p.s. bored at work
The only odor my older cars would produce would be that of natural exhaust coming from the tail pipes and only noticable when trainling behind the car or if the car were stationary it was mildly noticable when standing near the rear (or side) of the car.
I've always been able to tune a carb so that it wasn't overly rich and I would only hope that a sequential fuel injected motor would be better then even a tuned Q-Jet.
At the very least, I would hope that my Vette is not leaving so much fuel unburned that it would cause 'me' to stink. I think that if that were the case I'd want to fix that condition before installing cats.
I dunno, I think cats were only created to satisfy the EPA nuts and a well tuned engine should run quite clean without them, sure it wont be pure C02 and H2O coming outta the tail pipes, but certainly not raw fuel.
Lastly, it is good to be concious about the environment, but if I were that worried about it I'd be driving a Prius not a Vette. And it should be shunned to run catless on a C5 when its perfectly acceptable to run catless on an LT-1 '70 Vette.
p.s. bored at work
Moderator
Joined: Jun 2004
Posts: 22,538
Likes: 934
I hear the responses about the strong smell that these C5's produce when running without cats. I am getting more and more curious about this. I can't imagine how the C5 is much different than any of my older hot rods and muscle cars and they never produced a strong smell.
The only odor my older cars would produce would be that of natural exhaust coming from the tail pipes and only noticable when trainling behind the car or if the car were stationary it was mildly noticable when standing near the rear (or side) of the car.
I've always been able to tune a carb so that it wasn't overly rich and I would only hope that a sequential fuel injected motor would be better then even a tuned Q-Jet.
At the very least, I would hope that my Vette is not leaving so much fuel unburned that it would cause 'me' to stink. I think that if that were the case I'd want to fix that condition before installing cats.
I dunno, I think cats were only created to satisfy the EPA nuts and a well tuned engine should run quite clean without them, sure it wont be pure C02 and H2O coming outta the tail pipes, but certainly not raw fuel.
Lastly, it is good to be concious about the environment, but if I were that worried about it I'd be driving a Prius not a Vette. And it should be shunned to run catless on a C5 when its perfectly acceptable to run catless on an LT-1 '70 Vette.
p.s. bored at work
The only odor my older cars would produce would be that of natural exhaust coming from the tail pipes and only noticable when trainling behind the car or if the car were stationary it was mildly noticable when standing near the rear (or side) of the car.
I've always been able to tune a carb so that it wasn't overly rich and I would only hope that a sequential fuel injected motor would be better then even a tuned Q-Jet.
At the very least, I would hope that my Vette is not leaving so much fuel unburned that it would cause 'me' to stink. I think that if that were the case I'd want to fix that condition before installing cats.
I dunno, I think cats were only created to satisfy the EPA nuts and a well tuned engine should run quite clean without them, sure it wont be pure C02 and H2O coming outta the tail pipes, but certainly not raw fuel.
Lastly, it is good to be concious about the environment, but if I were that worried about it I'd be driving a Prius not a Vette. And it should be shunned to run catless on a C5 when its perfectly acceptable to run catless on an LT-1 '70 Vette.
p.s. bored at work
Race Director
Joined: Apr 2007
Posts: 11,148
Likes: 889
From: South Western Ontario
It's a free country so you can do what you want Manley. Like I posted, for me personally vehicles with no cats stink. I can smell when an old car or uncatted car is way up the road ahead of me and if I'm close behind I always pass to get away from it. Actually, I'm somewhat sensitive to the exhaust and it also gives me a bit of a sore throat.
Honestly, it's not a really strong smell but it's not a nice smell and I find it sticks with you (and the interior of the car too for that matter).
Peter
Honestly, it's not a really strong smell but it's not a nice smell and I find it sticks with you (and the interior of the car too for that matter).
Peter
Melting Slicks
Joined: Dec 2004
Posts: 2,847
Likes: 1,144
From: Sleepy Hollow- NJ
Going on 7 years without the cats in mine and I dont mind the smell at all anymore. However when I have anoyone else in the car besides my wife they mention the raw fuel smell...but I don't care. At first I coulldn't decide if I hated it or not. It took a bit of getting used to. The car sounds awesome with the heads, cam, LT's, off road x-pipe and Borla Stingers. At WOT she really screams. Went on a car cruise with about 20 other cars this past summer and 4 drivers came up to me when we parked and said "that thing sounds great when you get in it". I can't help but think the catless setup contributes to that "great" sound.
I had the cats/02 sensors tuned out and she passed emissions. FYI
I had the cats/02 sensors tuned out and she passed emissions. FYI
Safety Car
Joined: Sep 2000
Posts: 3,568
Likes: 417
From: Taildragers rule! USA1
Going on 7 years without the cats in mine and I dont mind the smell at all anymore. However when I have anoyone else in the car besides my wife they mention the raw fuel smell...but I don't care. At first I coulldn't decide if I hated it or not. It took a bit of getting used to. The car sounds awesome with the heads, cam, LT's, off road x-pipe and Borla Stingers. At WOT she really screams. Went on a car cruise with about 20 other cars this past summer and 4 drivers came up to me when we parked and said "that thing sounds great when you get in it". I can't help but think the catless setup contributes to that "great" sound.
I had the cats/02 sensors tuned out and she passed emissions. FYI
I had the cats/02 sensors tuned out and she passed emissions. FYI
Whether you "don't mind the smell" is irrelevant. Hydrocarbon emissions, carbon monoxide and nitrous oxides are pouring out your exhaust.
Do you walk around in your soiled diapers as well?
Safety Car
Joined: Sep 2000
Posts: 3,568
Likes: 417
From: Taildragers rule! USA1
Not exactly. Federal law requires catalytic converters. I guess you can do anything you want until you get caught.
Scoffing at the law and running around smelling like a toilet is brainless self centered selfishness.
Scoffing at the law and running around smelling like a toilet is brainless self centered selfishness.
Burning Brakes
Joined: Mar 2010
Posts: 1,189
Likes: 4
From: Freeport, FL
Eh, we all break rules and defy "the man" here and there; it’s just interesting how we only become self-righteous and overly opinionated when on a chat forum. Yes, cats are a federal law. But, law also prohibits from modifying the stock exhaust system form its original state. I am quite sure that all of you who are preaching to us have in some form modified you exhaust. As far as laws go, I’m sure the sound level exceeds legal limits for many of us, even us with cats. I’m sure many of us break laws, speeding, having a few drinks and then driving (note: I don’t drink), changing lanes without signaling, tearing the label off mattress’, etc etc……
As far as this statement, “Hydrocarbon emissions, carbon monoxide and nitrous oxides are pouring out your exhaust.”
Well, my 375hp 86 Camaro Z28 passed its emissions test and I had removed ALL computer and emissions (it did have the PCV system, but that was it). I am, and it IS possible to tune a carb to run quite efficiently. I don’t go for highest horsepower, I just match components and tune them to run as well as that combo can run. Could a few extra hp be realized, yes, but I prefer power and efficiency.
“Don't do it, you will most likely regret it.”
Perhaps we will regret it and maybe not. That’s the fun of hot-rodding, trial and error. How many have installed a cam and then went bigger or smaller, installed a stereo and then ripped it out to change to something else, etc etc???
Well, I could keep going, but you guys get the point. This forum rocks and you all are great
Hey, who’s going to the LSX Shoot out Sunday at Gateway in St. Louis?????
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Safety Car
Joined: Sep 2000
Posts: 3,568
Likes: 417
From: Taildragers rule! USA1
:
As far as this statement, “Hydrocarbon emissions, carbon monoxide and nitrous oxides are pouring out your exhaust.”
Well, my 375hp 86 Camaro Z28 passed its emissions test and I had removed ALL computer and emissions (it did have the PCV system, but that was it). I am, and it IS possible to tune a carb to run quite efficiently. I don’t go for highest horsepower, I just match components and tune them to run as well as that combo can run. Could a few extra hp be realized, yes, but I prefer power and efficiency.
?
As far as this statement, “Hydrocarbon emissions, carbon monoxide and nitrous oxides are pouring out your exhaust.”
Well, my 375hp 86 Camaro Z28 passed its emissions test and I had removed ALL computer and emissions (it did have the PCV system, but that was it). I am, and it IS possible to tune a carb to run quite efficiently. I don’t go for highest horsepower, I just match components and tune them to run as well as that combo can run. Could a few extra hp be realized, yes, but I prefer power and efficiency.
?
So you are THAT much smarter than the engineers at GM and the EPA. You need to write up a white paper on your tuning abilities and go for a Nobel prize.
Right now, you'd only get one for serving too much baloney.
Drifting
Joined: Sep 2007
Posts: 1,638
Likes: 50
From: Goldsboro NC
Safety Car
Joined: Jul 2005
Posts: 3,572
Likes: 9
From: Jackson Tn
St. Jude Donor '06-'07-'08-'09
I'm quite impressed with Manleys modding and tuning abilities. Yank off the cats and put on Borla straight pipes then tune it with a DiabloSport. Yep, he's an expert
Melting Slicks
Joined: Feb 2007
Posts: 3,266
Likes: 8
From: Indian Rocks Beach FL
St. Jude Donor '08-'09-'10
Drifting
Joined: Jan 2008
Posts: 1,722
Likes: 138
From: Florida
St. Jude Donor '09
http://www.catalyticconverter.org/law/index.htm
Last edited by ipuig; Oct 11, 2010 at 01:03 AM.
Melting Slicks
Joined: Feb 2007
Posts: 3,266
Likes: 8
From: Indian Rocks Beach FL
St. Jude Donor '08-'09-'10
Fuctioning coverters cannot be removed, the OEM configuration cannot be modified to stay within the law. All of you running high-flow cats are technically in violation of federal law regardless of your emmisions test results.
http://www.catalyticconverter.org/law/index.htm
http://www.catalyticconverter.org/law/index.htm
Long tube headers are not in themselves illegal but require the cats to be relocated, which is illegal. Some shorty headers are legal and carry CARB numbers.
Burning Brakes
Joined: Mar 2010
Posts: 1,189
Likes: 4
From: Freeport, FL
My skills are quite impressive. And as we all know chicks dig guys with skills
Some people are just "know it all d@uches".
Racer
Joined: Nov 2006
Posts: 380
Likes: 1
From: Janesville Wisconsin
Drove mine for 3 years stock with hollowed out cats. never smelled a thing, had check engine light on, but never had anything done, ran fine. Why wouldnt it make a difference? Its louder, flows more... duh. I always wonder why people change the cat back and not change the cats. Kind of half-assed if you ask me.
It was not much louder. If your modifying your car and are concerned about the 1 decibal increase you should probably get another hobby.
Now its rebuilt, 224R cam, and Ti cat back.... still isnt that loud. If you want power w/ and a quiet car build a turbo car.
It was not much louder. If your modifying your car and are concerned about the 1 decibal increase you should probably get another hobby.
Now its rebuilt, 224R cam, and Ti cat back.... still isnt that loud. If you want power w/ and a quiet car build a turbo car.
Drifting
Joined: Sep 2007
Posts: 1,638
Likes: 50
From: Goldsboro NC
Drove mine for 3 years stock with hollowed out cats. never smelled a thing, had check engine light on, but never had anything done, ran fine. Why wouldnt it make a difference? Its louder, flows more... duh. I always wonder why people change the cat back and not change the cats. Kind of half-assed if you ask me.
It was not much louder. If your modifying your car and are concerned about the 1 decibal increase you should probably get another hobby.
Now its rebuilt, 224R cam, and Ti cat back.... still isnt that loud. If you want power w/ and a quiet car build a turbo car.
It was not much louder. If your modifying your car and are concerned about the 1 decibal increase you should probably get another hobby.
Now its rebuilt, 224R cam, and Ti cat back.... still isnt that loud. If you want power w/ and a quiet car build a turbo car.
Burning Brakes
Joined: Sep 2010
Posts: 901
Likes: 1
From: LaPorte Indiana
