DIY: Gutting out your Catalytic Converter
#77
No respecter of malarkey
iTrader: (25)
I do my part as best I can. Excuses are only that. If I'm fortunate I won't have to suffer from the consequences as a result of selfish excuse makers on their low horses ... even though it likely won't matter in my lifetime I care about the future of the human life support system the same. If you were old enough to have lived in one of the major metropolises like Los Angeles before the use of emission controls then you would know the air is better today than it was then despite the substantial population/industrial/automotive vehicle differences between now and then. It does matter. Shortsighted denial doesn't change this.
#78
Holy **** Snacks.. Cat's were invented for LEADED GAS..and now that they've added so much, (15% Corn) in it, There's NO need to even install them at the Factory.. Its a Known Trouble spot for this Car and a Known Killer of these engines.. Poking a Whole threw it is just extending the Enjoyment of this car.. Im in my 40's now,and OUR Government has consistently Feed us BS and Lies.. I also Have my EPA license for Freon..which they Said was Destroying the Ozone etc etc..But they left the Trillions of Gallons of Chlorinated Pool Water out of the Equation.. And Do ya think when the Shuttle was in Operation it was Solor Powered? Mature Nature will Survive.. She Always has.. (Soap Box put back in closet now)
#79
My point is that the RX8 is one of the least economical cars on the road. Preaching to RX8 owners that they should not gut their cat will 99% of the time fall on deaf ears. Most people did not buy the 8 because it was economical/ to save mother earth...
Trying to save you some grief as I can see that you are very passionate about this topic...You will not convince people on this forum to agree with you...but if you want to continue to try go on with your bad self
PS- My 8 still has its cat on
#80
Registered
iTrader: (4)
I'm going to side with Mark on this.
You can sell a perfectly good cat to help pay for an alternative replacement pipe. That may be a midpipe or a high flow cat. My preference would be a high flow cat. It eliminates some of the problems that have to be worked out with a midpipe. I am driving a street car that only intermittently sees track duty. If I was racing where time matters, my priorities would be different.
Where we may not see it the same is when you have a clogged cat. I could see a person, getting in there and opening it up.
You can sell a perfectly good cat to help pay for an alternative replacement pipe. That may be a midpipe or a high flow cat. My preference would be a high flow cat. It eliminates some of the problems that have to be worked out with a midpipe. I am driving a street car that only intermittently sees track duty. If I was racing where time matters, my priorities would be different.
Where we may not see it the same is when you have a clogged cat. I could see a person, getting in there and opening it up.
#81
Registered
iTrader: (15)
Although Mark makes a good point ... we fail to consider the side effects of the production of catalytic converters.
Remember that CC's contain platinum and palladium to help convert noxious gasses into CO2. One could say "hey that's beneficial to the health of our environment" which is what many of the greenies like to bitch and moan about when they give those who do not use CCs the arrogant snub ... yet the educated would make the further point that "did you know that platinum must be mined and refined before it is used in a CC? A process that takes over a year? Did you know mining is just as harmful to our environment? Did you know mining causes deforestation, death, pollution?"
There will always be arguments for and against a process when talking about our environment.
Remember that CC's contain platinum and palladium to help convert noxious gasses into CO2. One could say "hey that's beneficial to the health of our environment" which is what many of the greenies like to bitch and moan about when they give those who do not use CCs the arrogant snub ... yet the educated would make the further point that "did you know that platinum must be mined and refined before it is used in a CC? A process that takes over a year? Did you know mining is just as harmful to our environment? Did you know mining causes deforestation, death, pollution?"
There will always be arguments for and against a process when talking about our environment.
#82
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Location: Waukesha, WI
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I think it depends on the purpose for doing a gutted cat. If this is your daily diver, why do it?
To get such a small amount of power where you wont even notice it. The RX8 is slow, deal with it. Unless you have the money to make it fast just leave it alone. If it is for sound, straight pipe the resonator or get a better muffler, why the cat?
If you actually have a project and actually have some good mods, gutting at cat will benefit you. The stock exhaust is so restrictive, you will lose power from it. Its all about supporting mods. Especially with forced induction. Once you start pushing that much air in, it needs to come out that fast too.
Some comments about back pressure and how you need it. Even with a complete stock car there would be plenty of back pressure with a gutted cat. On a turbo @ 14 with every bolt on you could possibly do, even a 3'' straight pipe all the way back would have back pressure. No matter what, the headers will restrict flow and create back pressure. Drag cars would run right off the heads if they could. They can't, the car would burn down.
You don't want back pressure. It is restricting the flow stopping you from adding more air/fuel (of course other factors to). You tune the car to match all your supporting mods.
Now we are getting better at engineering and designing exhausts systems that will help push the air out. Like a vortex giving a better performance and a better tone then a straight piped exhaust of the same size.
The point of the exhaust is for emissions and sound. If you take those factors out the best performance would be with no headers at all. You would differently need to tune for it and some how stop the car from burning down.
Now for the emission test. They don't put a hose over your exhaust anymore. They plug into your ecu to see if there is any codes or stored codes and that is it. If you don't have any you pass, have them you fail.
I will tell you how to over come cel with a gutted cat or straight pipe. It's called a spark plug fouler. You find the closest size to the original O2 bung. You will then re tap the threads to fit in the bung and then re tap the threads for the O2 to screw into. Here is a pic to get a better idea what it looks like. Spark Plug Fouler Installed
The reason for this is you get to adjust the amount of fumes the O2 reads. Letting you adjust to the point where the ecu thinks the cat is there and working.
To get such a small amount of power where you wont even notice it. The RX8 is slow, deal with it. Unless you have the money to make it fast just leave it alone. If it is for sound, straight pipe the resonator or get a better muffler, why the cat?
If you actually have a project and actually have some good mods, gutting at cat will benefit you. The stock exhaust is so restrictive, you will lose power from it. Its all about supporting mods. Especially with forced induction. Once you start pushing that much air in, it needs to come out that fast too.
Some comments about back pressure and how you need it. Even with a complete stock car there would be plenty of back pressure with a gutted cat. On a turbo @ 14 with every bolt on you could possibly do, even a 3'' straight pipe all the way back would have back pressure. No matter what, the headers will restrict flow and create back pressure. Drag cars would run right off the heads if they could. They can't, the car would burn down.
You don't want back pressure. It is restricting the flow stopping you from adding more air/fuel (of course other factors to). You tune the car to match all your supporting mods.
Now we are getting better at engineering and designing exhausts systems that will help push the air out. Like a vortex giving a better performance and a better tone then a straight piped exhaust of the same size.
The point of the exhaust is for emissions and sound. If you take those factors out the best performance would be with no headers at all. You would differently need to tune for it and some how stop the car from burning down.
Now for the emission test. They don't put a hose over your exhaust anymore. They plug into your ecu to see if there is any codes or stored codes and that is it. If you don't have any you pass, have them you fail.
I will tell you how to over come cel with a gutted cat or straight pipe. It's called a spark plug fouler. You find the closest size to the original O2 bung. You will then re tap the threads to fit in the bung and then re tap the threads for the O2 to screw into. Here is a pic to get a better idea what it looks like. Spark Plug Fouler Installed
The reason for this is you get to adjust the amount of fumes the O2 reads. Letting you adjust to the point where the ecu thinks the cat is there and working.
#86
#87
i know this is an old thread but if anyone is stll out there coud u help i have 2004 rx8 74000 miles 192bhp i bought it in feb of this year the man i bought it from had just had coils,plugs and leads done. the car ran fine for about a month and then started developing hot start problems so i evantually bought a new uprated starter thinking it would be that, it came on friday. but before i installed it i had put some of the more expensive premium petrol in for a change 10 mins later on a dual carriageway the car cut out at the lights and would not start for 30 mins and sound really rough when it did for a few seconds then i nursed it home keeping revs on all time. this morning went to install the new starter only to find it allready has the uprated one on. i know the cat is f....ed as it sounds like a bag of bolts rattling round, just would lile to know if gutting my cat for the time being would make it run better do not have the cash for a new cat or compression test, any other ideas or checks/cleans i could do thanks
#88
bag of bolts sounds weird....the cat is ussually a silent killer
easy test is to just unbolt the cat from the exhaust manifold and start her up no need to fully remove it.
if the car starts and drives fine then recycle the cat for some quick dollars and get a mid pip (gutted cats are worth $0)
dont drive the car around with the cat unbolted for more than 5 miles or youll end up replacing the whole exhaust
easy test is to just unbolt the cat from the exhaust manifold and start her up no need to fully remove it.
if the car starts and drives fine then recycle the cat for some quick dollars and get a mid pip (gutted cats are worth $0)
dont drive the car around with the cat unbolted for more than 5 miles or youll end up replacing the whole exhaust
#91
finally got the cat off today but the actual rattle noise is coming from the back section of pipe ( the small straight piece before it gets to the backbox) could this be the damged cat bits blown through or is my exhaust knackered as well
#93
could i start my car with no cat on at all or would that be a big no no please note if i were to start it i would have to leave it running 10 mins to let it warm up otherwise i would have a flood to deal with
#95
You gonna eat that?
iTrader: (1)
Seems unlikely, just wondering if anybody has heard of it happening.
#97
anyone got any more info on wheter the cat looks like its had it or should i just go ahead and gut it anyway also could some one tell me what is actually meant to come out of the cat if i were to gut it
#98
that cats in tact and clogged like a **** but i dont think its causing the sound
when gutting you will break the honeycomb material it looks like charcoal also some insulation its easier to break dry but the insulation is easier to remove wet
so get all the material out and then hose it down
when gutting you will break the honeycomb material it looks like charcoal also some insulation its easier to break dry but the insulation is easier to remove wet
so get all the material out and then hose it down
Last edited by -_- just.gimme.my.ticket; 06-12-2013 at 08:10 PM.