Has Anyone Attempted the Removal of the Cats...
- Thread starter LOSTR4
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LOSTR4
Member
Well, the state I live in (where car is to be registered) doesn't have emissions, so I'm hoping to squeak by if there were a feasible route to take. Most vehicles gain a lot from losing much of the emissions...not just including performance but even more with fuel economy. I modded the EGR on my Audi and I'm getting roughly 4-5 more MPG than others with it properly functioning. I'm basically tricking my motor to only see cool, fresh air instead of it breathing its own farts...
Doesn't matter if your vehicle has emission testing or not.. .Modifying anything on the emissions is a FEDERAL crime...with punishment of a $10k fine and up to one year in prison.
As for performance...Doubtful you have much gain in hp or performance. Not going to reprogram the ECU. What can be done is put a O2 sensor feed that sends a false signal to the ECU. But that sends a steady signal..and doesn't account for different engine loads.
As for performance...Doubtful you have much gain in hp or performance. Not going to reprogram the ECU. What can be done is put a O2 sensor feed that sends a false signal to the ECU. But that sends a steady signal..and doesn't account for different engine loads.
oljedi11950
New member
Cats removal
Don't we have 4 total ? Thought I read over n performance zone some of the guys moving the y-pipe & taking those rear cats off , leaving fwd o2 sensors & cats , maybe search over there ? Or maybe is over on 120 forum ? Getting old
!!
Don't we have 4 total ? Thought I read over n performance zone some of the guys moving the y-pipe & taking those rear cats off , leaving fwd o2 sensors & cats , maybe search over there ? Or maybe is over on 120 forum ? Getting old
!!
stevec5000
New member
To get rid of the cats you would have to remove the entire exhaust system then get new headers and a new exhaust system and muffler. That would allow you to install a high performance system in place of the stock system. However if you remove the O2 sensors the Check Engine light will always be on and it may not run properly without the sensors. You could have a bung welded onto the new headers at the front to take the front sensors but loss of the rear ones would always be a problem unless you built a circuit to fool the ECM. It can't be reprogrammed but if you make a voltage divider that produces the same voltage output as the rear O2 sensors you may be able to fool it. Normally they put out approx. 0.5 volt when the engine is warmed up and running with the correct mixture but the rear ones produce a lower output since they are after the cat where there is less emissions. Making it adjustable and setting the output to around 0.1 volt may work. I would leave it alone and just install a cat back system if you want it to be louder.
LOSTR4
Member
I'm not after a louder exhaust, but that would be a fine bi-product if it was done right. I doubt I'll do anything with this but I was curious if anyone has...I'll check out the performance side of the forums and see what others have done...I'm sure it can be done with tricking the ECM but it seems to be a lot of work for a possible small gain...thanks for the advice and responses!
Brazenhead
New member
I have a 2000 V8 Tundra that has the cats removed. The truck is lifted (3") and I'm running 33's and averaging around .
I have noticed little to no increase in fuel economy or extra power, although I was told the same as you were. What I did notice is the noxious smell of the exhaust. The fumes seem ten times as bad. I'm also throwing codes P0420 and P0430 which are both related to the cats. Thankfully I have a scan gauge so I just clear them periodically.
Im in an area where there are no laws enforcing emissions controls, so when your cats go bad you cut them out. Oh and you do not have to replace your entire exhaust in order to do it.
My suggestion would be to simply leave it be. Throw a nice muffler on it remove the resonator and have you exhaust exit out the side behind the rear tire.
I have noticed little to no increase in fuel economy or extra power, although I was told the same as you were. What I did notice is the noxious smell of the exhaust. The fumes seem ten times as bad. I'm also throwing codes P0420 and P0430 which are both related to the cats. Thankfully I have a scan gauge so I just clear them periodically.
Im in an area where there are no laws enforcing emissions controls, so when your cats go bad you cut them out. Oh and you do not have to replace your entire exhaust in order to do it.
My suggestion would be to simply leave it be. Throw a nice muffler on it remove the resonator and have you exhaust exit out the side behind the rear tire.
LOSTR4
Member
That is most likely the route I will take. I appreciate your advice and I may have to do some welding this weekend to route the exhaust and throw on a tip...no reason to fix it (remove them) until they clog up.
Whitebeauty
New member
Probably but it's against federal emissions laws to remove, modify or disable. I think I remember reading somewhere that it can carry fines up to $10k.
This is funny........
OP..check out URDUSA.com THEY HAVE WHAT U NEED THERE TO REMOVE YOUR REAR CATS...and more....GL.! Your gonna love it.
LOSTR4
Member
Woot woot! Thank you Whitebeauty!
stevec5000
New member
If he's not in the US then it doesn't matter what federal regulations there are. However, removing the cats won't make any difference in performance except at wide open throttle where you want max air flow so unless there is going to be a lot of drag racing it doesn't make sense. In that case you'd probably have to make other mods to take advantage of the extra exhaust flow by opening up the intake, etc. The vehicle is rather big and heavy for drag racing though so I wouldn't bother with any mods.
Whitebeauty
New member
Its not for drag racing its for the joy of the ride. Thats why I supercharged my truck. Sure I like speed but if theres a car driving on the street like a turtle better yet stopped and I need to move guess what im movin....
LOSTR4
Member
I'm not a drag racer by any means...nor did I buy the correct vehicle for such endeavors. However, like Whitebeauty suggested, it's merely for the joy of the ride...and if it had any progressive effects to the efficiencies of the vehicle than by all means. Nonetheless, thank you for the advice and suggestions; they're all appreciated.
There are alot of lawyers on here. I will not get into a pizzing match with anyone. However I will point you to URD (under dog racing)
I have seen them re map a 4th gen v8 to run nearly 40mpg. It leans the vehicle out ALOT and has to be used on open highway to prevent overheating. but they make a USB programmer.
Talk to Gadget he knows more about the 4th gen than Toyota
zonianbrat
New member
10K in fines huh? I'd like to see someone get fined 10k for removing their cats and fooling some 02 sensors. Even in Denver they give you 3 chances to get your truck to pass emmissions and if it doesnt after 3 chances and like 2,000 bucks spent they give you a pass for a year. So they allow you to run it as bad as you want. It's your truck do whatever you want with it.
What!!!...????
Ok, Einstein bridge me on this silliness... Lets start.....
"Even in Denver...."
Dude, Denver has no emmisions laws. Pull yourself up out of the hole and look at the sticker, it says Colorado.
"They give you 3 chances...."
So, am I missing something? I get 3 chances to be in compliance of the law???
Sweet!
Oh, wait, maybe not so sweet.
"and like 2,000 bucks spent they give you a pass for a year."
So, class, pay attention, in Denver:
When you cut out your cats you are totally ok because....
1. When you have to renew your sticker you get 3 chances
2. Then you get to spend $2000 (for what is completely beyond me)
3. You get a 1 year grace....
But, the good news is "it's your truck and you get to do whatever you want."
Ugh
.
I got no coin in this. If someone can not have to wade around in federal government/EPA shit, more power to you.
I have just done an hour of searching the interwebs looking for anything that resembles a discussion regarding underdog racing and 4runners and cats and 40 mpg. There is no emmisions in Mexico. I'd love to see something that suggests this is possible.
.
zonianbrat
New member
You are hilarious.....really. Did you live in Denver? I did (granted it was a few years ago). I had a pathfinder with no cats. Failed emmissions. And yes they have emmissions tests. They also sit on the on-ramps with a box van set up to monitor your emmissions as you drive by. They take a pic of your tag if it fails. When I failed I was told to come back after trying to fix whatever made me fail (they will give you a printout with your specs).You can spend like 2000 before they give you a pass for a year. Yeah.....ugh is right. That was Denver....Ft. Collins has recently stopped requiring emmissions. I live by Steamboat Springs and there is no emmissions here. Oh and he said he didnt have emmissions where he lived anyway...
Feelin "Bridged"??? Guess what.....It was my truck and I did what I wanted with it!:wow2:
Einstein out.....
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