No Cats........Any Problems????
Pro
Joined: May 2000
Posts: 610
Likes: 1
From: Midland Texas
St. Jude Donor '09-'11
The Catco high flow convertors that come with the LG longtubes have been fine on our C6 for 5000 miles running as lean as 13.1:1 air fuel ratio at WOT for 12 seconds at a time. I would think they would survive fine on a power adder car, especially with long tubes where the exhaust gas cools some before entering the cats.
You might want to call LG and ask them if they have seen any chronic problems with cats on power adder cars, and, if so, was it an open track or an open road race car or a drag car and what they attribute the failure to. I only have experience on a few cars.
Joe
You might want to call LG and ask them if they have seen any chronic problems with cats on power adder cars, and, if so, was it an open track or an open road race car or a drag car and what they attribute the failure to. I only have experience on a few cars.
Joe
Le Mans Master
Joined: Feb 2006
Posts: 5,762
Likes: 4
From: Chandler Arizona
One more thing about running without Cats. Go over to LS1tech.com and quite a few people run Cats for the sound. I've always run Cats, so I can't say first hand, but people claim that the Cats remove "rasp." Some of the comments I've read over there when I had my Camaro was that without cats, the LS1 sounded like an old garbage truck.
Race Director
Joined: Mar 2005
Posts: 10,052
Likes: 17
Race Director
Joined: Mar 2005
Posts: 10,052
Likes: 17
FYI, for those of you wondering how some 'high performance' cats may hold up to your 'high performance' usage.
My cats after a few months of hard driving (no HPDE's, just spirited driving on stock engine/stock tune long tube headers, vararam, 12.5-12.8 a/f ratio at WOT:
My cats after a few months of hard driving (no HPDE's, just spirited driving on stock engine/stock tune long tube headers, vararam, 12.5-12.8 a/f ratio at WOT:
Race Director
Joined: Mar 2005
Posts: 10,052
Likes: 17
Le Mans Master
Joined: Dec 2004
Posts: 5,492
Likes: 807
From: West coast CA
3-way catalytic converters oxidize HC and CO and reduce oxides of nitrogen, which benefits the environment by reducing emissions of gases which are 1) toxic and 2) components of smog and acid rain.
Catalysts were not invented to address global warming and nobody claims that they do. If anything, they actually increase nitrous oxide and (total) CO2 emissions, which are so-called greenhouse gases. So I guess in that sense this does have something to do with global warming, just in the opposite way than you suggested.
Catalysts + closed-loop engine management systems have dramatically reduced the emission of manifestly poisonous gases from cars. The reduction of HC emissions alone is obvious to anybody standing nearby. This is principally a local, not global, pollution problem, and it's hardly subtle. Visit someplace with a fleet of older, dirty cars and take a whiff.
Instructor
Joined: Jul 2007
Posts: 114
Likes: 0
From: Cottonwood AZ
I went catless on my Vette and I am currently catless on my Viper. What did everyone do back in the 60's and 70's when there was no cats? They smelled unburnt exhaust. It's not bad. Do it. I loved the sound. On my Viper it makes a huge difference in the side sill temps. Those cats get DAMN hot. No more burnt legs when I get out...lol.
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Instructor
Joined: Jul 2007
Posts: 114
Likes: 0
From: Cottonwood AZ
Safety Car
Joined: Jun 2005
Posts: 3,989
Likes: 5
From: DFW This user does not support or recommend the product or service displayed in the ad to the right
**** you and your stinky cars. You guys do realize what you are admittedly doing and talking about on the internet is illegal in all 50 states, has hefty penalties including jail time and anyone that knows what you are doing can turn you in to the feds?
Last edited by C6400hp; Jul 10, 2007 at 01:42 AM.
Instructor
Joined: Jul 2007
Posts: 114
Likes: 0
From: Cottonwood AZ
Right, so since I think it is irresponsible to drive around in a vehicle without cats ( it is also illegal by the way) You think I need to ride a bike?
**** you and your stinky cars. You guys do realize what you are admittedly doing and talking about on the internet is illegal in all 50 states, has hefty penalties including jail time and anyone that knows what you are doing can turn you in to the feds?
**** you and your stinky cars. You guys do realize what you are admittedly doing and talking about on the internet is illegal in all 50 states, has hefty penalties including jail time and anyone that knows what you are doing can turn you in to the feds?
I do not live in any of your 50 states, so send your federales after me all you want! How about a group hug?
Please stop beating that dead horse. Wanna discuss the environment, please give Gore a call and jumb on his bandwagon!
Safety Car
Joined: Jun 2005
Posts: 3,989
Likes: 5
From: DFW This user does not support or recommend the product or service displayed in the ad to the right
It is nice to know that you dont agree with my opinion. Thats probably good for you since I think you are a doucherocket. How about contributing to the thread and the OP's question rather than going off on your Al Gore tirade.
Instructor
Joined: Jul 2007
Posts: 114
Likes: 0
From: Cottonwood AZ
Great, no more burt legs for you, Burnt lungs for the rest of us. 
Thanks
Just remember
Hollowing out a catalytic converter or replacing it with a test pipe or straight section of pipe is a violation of Federal Law punishable by fines in excess of $25,000 and/or jail time for both the vehicle owner and the person doing the work.
Removing a catalytic converter will result, at most, in 5 HP in power improvement.
ThanksJust remember
Hollowing out a catalytic converter or replacing it with a test pipe or straight section of pipe is a violation of Federal Law punishable by fines in excess of $25,000 and/or jail time for both the vehicle owner and the person doing the work.
Removing a catalytic converter will result, at most, in 5 HP in power improvement.
Like many have said and there are pictures to prove it, it is possible to blow the heck out of cats with or without headers. (I think mostly with).
Yes, of course, the environment is a very important thing that has seemingly come to the forefront of all media and therefore political arena. Like I said, I am from Canada. I have been recycling and saving my water for at least 15 years, so please give me a break. As for the Gore thing, I like the guy, I felt compelled to wear a Gore pin when he was campaigning against Bush as I felt he was a much better candidate. At least much more intelligent...
I hope I don't start another tangent on this ramble.
To answer the OP, I am sorry to have sort of hijacked your thread. I was interested originally because I am thinking of doing the same thing and was particularly wanting to know if there was any need to re-tune the engine after I install a C6 Z06 exhaust and center pipe as well as remove the cats. Thanks. I am all ears; really!
Thread Starter
Burning Brakes
Joined: Mar 2006
Posts: 946
Likes: 0
From: Midland, TX........ 550 RWHP/520 RWTQ (A6)
O.K..............let's not get the thread shut down. Stop with the name calling and start acting like adults. If you've stated that you're against not running cats......fine, we know your opinion.....we don't need to hear it again. And for a second time......my question has nothing to do with deleting cats for a small gain in hp........I'm running cats now. My question was asked because of the hi flo cats coming apart (especially on a FI car). I'm asking people without cats for feedback. If everyone can't act like adults, I'll ask the moderator to lock the thread. Everytime this subject comes up......this is what happens and the thread gets hijacked and then locked.
Thanks to everyone that's offered helpful feedback.
Thanks to everyone that's offered helpful feedback.
Burning Brakes
Joined: Jul 2005
Posts: 779
Likes: 2
From: Bloomingdale Illinois
My experience
.....I have dynatec 1 7/8 headers with the high flow cats that came with them on my C6 going through Corsa sports.
.....I was really concerned about the Cat internals due to the amount of boost I was going to run melting and blowing apart inside going through my exhaust getting pieces stuck in my mufflers.
I put them on anyway at 2000k miles, and decided to take a look after a while and see what they look like. The car now has 9500 miles.
I have over 20 WOT dyno runs at 14 psi of boost to 7600 rpm. Many many street blasts and my AFR is set on the rich side at 11.5. I had my exhaust down 2 weeks ago and inspected my converters. I was so so happy when I looked inside and I could see perfectly through the honeycomb and shown no signs of heat fatigue.
My cam is over 600 lift and 236* duration and with all the thumping it does at an idle, there is barely a smell which is really nice having a convertible.
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.....I was really concerned about the Cat internals due to the amount of boost I was going to run melting and blowing apart inside going through my exhaust getting pieces stuck in my mufflers.
I put them on anyway at 2000k miles, and decided to take a look after a while and see what they look like. The car now has 9500 miles.
I have over 20 WOT dyno runs at 14 psi of boost to 7600 rpm. Many many street blasts and my AFR is set on the rich side at 11.5. I had my exhaust down 2 weeks ago and inspected my converters. I was so so happy when I looked inside and I could see perfectly through the honeycomb and shown no signs of heat fatigue.
My cam is over 600 lift and 236* duration and with all the thumping it does at an idle, there is barely a smell which is really nice having a convertible.
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Burning Brakes
Joined: Dec 2004
Posts: 810
Likes: 1
From: Turbocharged in NC
Does anyone know if the Billy Boat X-Pipe with high flow cats can stand up to the APS twin turbo system with 8psi of boost? These are the only bolt on cats I've found for the APS system except for APS's own exhaust system.
I have the twins on my car and don't want to spend the big $2000 price tag of the APS 3 inch exhaust, that is, unless someone knows where I can get it cheaper, so I was thinking that spending $500 on the Billy Boat X-Pipe with High Flow Cats might be a better option. I can't find any good info anywhere on how exhaust flow is calculated through cats and what flows different cats are rated for, it doesn't seem to be easy to tell what cat flows how much for what power.
I called Billy Boat and they were no help at all. APS, of course, just wants to sell their exhaust. Lots of non-information.
Any info that anyone has on this system I would appreciate.
Thanks
I have the twins on my car and don't want to spend the big $2000 price tag of the APS 3 inch exhaust, that is, unless someone knows where I can get it cheaper, so I was thinking that spending $500 on the Billy Boat X-Pipe with High Flow Cats might be a better option. I can't find any good info anywhere on how exhaust flow is calculated through cats and what flows different cats are rated for, it doesn't seem to be easy to tell what cat flows how much for what power.
I called Billy Boat and they were no help at all. APS, of course, just wants to sell their exhaust. Lots of non-information.
Any info that anyone has on this system I would appreciate.
Thanks
Last edited by wewing; Jul 10, 2007 at 09:09 PM.
Instructor
Joined: Jul 2007
Posts: 114
Likes: 0
From: Cottonwood AZ
O.K..............let's not get the thread shut down. Stop with the name calling and start acting like adults. If you've stated that you're against not running cats......fine, we know your opinion.....we don't need to hear it again. And for a second time......my question has nothing to do with deleting cats for a small gain in hp........I'm running cats now. My question was asked because of the hi flo cats coming apart (especially on a FI car). I'm asking people without cats for feedback. If everyone can't act like adults, I'll ask the moderator to lock the thread. Everytime this subject comes up......this is what happens and the thread gets hijacked and then locked.
Thanks to everyone that's offered helpful feedback.
Thanks to everyone that's offered helpful feedback.
Better yet, pedal off into the sunset!
Le Mans Master
Joined: Oct 1999
Posts: 8,205
Likes: 40
From: Tucson AZ
It is considered a FELONY to remove the cats. You would (probably) never get caught, but is it worth it? I have tried what seems like every possible exhaust combo, and my answer would be no.
Instructor
Joined: May 2007
Posts: 211
Likes: 0
From: Mountain View CA
I've run 3 turbo cars with high flow cats...My TT 3000GT VR4, mild mods, no problems, and 2 mid 12s to high 11 second DSMs (AWD turbo) for thousands of miles at some damn high EGTs and never damaged one of my catalytic converters. I should mention that I beat on the two DSMs really hard, pretty much WOT nearly all the time as well, I was not a conservative driver a few years ago. Also, please don't say "12s is slow, who cares" because for a little bitty 2 liter engine with relatively minimal money spent on modifications, thats pretty damn impressive IMHO.
Typically when I tuned the DSMs I would see max EGTs of around 1600* F during a WOT pull (didnt want to push it any higher for fear of engine damage). Even at these extreme EGTs from a turbo motor there was no damage to the catalyst, and theres only ONE cat for all the exhaust to get past, unlike the vette where there are a pair of headers and heads to split the gas through....
For the minimal gains you'd see, please just find a quality high flow cat and keep your car from being a gross polluter. I should also mention that with turbo cars there is a lot more to gain from no cat vs high flow cats, we're talking NA here...No brainer.
Typically when I tuned the DSMs I would see max EGTs of around 1600* F during a WOT pull (didnt want to push it any higher for fear of engine damage). Even at these extreme EGTs from a turbo motor there was no damage to the catalyst, and theres only ONE cat for all the exhaust to get past, unlike the vette where there are a pair of headers and heads to split the gas through....
For the minimal gains you'd see, please just find a quality high flow cat and keep your car from being a gross polluter. I should also mention that with turbo cars there is a lot more to gain from no cat vs high flow cats, we're talking NA here...No brainer.
Melting Slicks
Joined: Oct 2006
Posts: 2,234
Likes: 61
From: Branford, Connecticut
We had emissions tests in the early and mid 90's, in Florida, at least in Dade and Broward counties anyway. Back then I used to have Mustangs. I would just hollow out my cats, just so when they out the mirror under the car they would see them. And the car used to pass all the tuime, with hollow cats. So exactly what do the cats do, if the car still passed without them? And I never noticed any smell. I think cats are a little overrated in the emissions they control.