Is anyone here very knowledgeable....

[audioholic 5,000+ posts]

If I know wtf Im talking about, any cat behind the O2 sensor is removable (tho not legally).

 

[Upgrayedd 10+ year member]

it isnt 4 cats those are resonators. all new model vehicles have at least 1 sensor precat and 1 sensor post cat for every cat in the system. some vehicles have 2 sensors, some 3 some 4 and some even have 5 sensors !


you have 2 cats dude look it up lol the rest are resonators only to help reduce noise level thats it. if it doesnt have a sensor it isnt a cat.

Stop spreading misinformation. There are plenty of vehicles that have 3-4 cats. Yes some have a cat and a resonator but many vehicles, especially in the last 5-10 years have a cat right off of the manifold and one further back. I have scrapped enough if these to know this.

BTW, you still haven't shown an aluminum flowmaster since you claim all of their race mufflers are.

 

[Buck 5,000+ posts]

Stop spreading misinformation. There are plenty of vehicles that have 3-4 cats. Yes some have a cat and a resonator but many vehicles, especially in the last 5-10 years have a cat right off of the manifold and one further back. I have scrapped enough if these to know this.
BTW, you still haven't shown an aluminum flowmaster since you claim all of their race mufflers are.

Since you seem to know a bunch, I gots a qwerstion for ya. I have 4 o2 sensors. My front cats convert the NOx right? And the HC/CO gases aren't measured by my rear o2 sensor?

 

[Upgrayedd 10+ year member]

I honestly can not tell you what cats do what percentage of what. We have removed both front and rear and as long as the sensor was after a cat, we never had an issue. That is not to say it isnt possible. HC and CO are not measured by either sensor. Oxygen percentage is what is measured. Anything other gas is just a lack of.

 

[Buck 5,000+ posts]

I honestly can not tell you what cats do what percentage of what. We have removed both front and rear and as long as the sensor was after a cat, we never had an issue. That is not to say it isnt possible. HC and CO are not measured by either sensor. Oxygen percentage is what is measured. Anything other gas is just a lack of.

Ok. So I believe my front ones are the only measured ones, even though the sensor is in the back. So that would mean I could relocate the sensor and mess with my 2nd set of them.

 

[Upgrayedd 10+ year member]

You need 1 sensor for air fuel monitoring that affects the ratio. This goes precat. Before any cat. The 2nd is for emissions, has no real effect on ratio but is a monitor for obd2. This has to be after a cat.

Edit. This is x2 for you since you have a v motor with 4 sensors.

 

[Buck 5,000+ posts]

You need 1 sensor for air fuel monitoring that affects the ratio. This goes precat. Before any cat. The 2nd is for emissions, has no real effect on ratio but is a monitor for obd2. This has to be after a cat.
Edit. This is x2 for you since you have a v motor with 4 sensors.

Ok. But the 2nd pair only monitor the first cats, not the second ones I believe. So the second set will not throw a light if the spontaneously combust and are no longer with us //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[Upgrayedd 10+ year member]

correct.

 

[Buck 5,000+ posts]

How sure are you of this? Just double checking, I'm sure you understand //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[Upgrayedd 10+ year member]

I'll never say %100 until I know it works. All I can say is on mustangs and lightnings we have put the post cat sensor after a single cat. Most were catless and had the 2nd sensor turned off in the tune but there were a few that were not.

 

[Buck 5,000+ posts]

I'll never say %100 until I know it works. All I can say is on mustangs and lightnings we have put the post cat sensor after a single cat. Most were catless and had the 2nd sensor turned off in the tune but there were a few that were not.

What do the first cats look like? If you look at the like I posted, do they look like the first ones or the second ones on the pipe in the link?

 

[twistedchild420 5,000+ posts]

Had a cat get clogged on my old cutlas....we cut that bish off and welded some pipe!

 

[Upgrayedd 10+ year member]

first ones are right off of the manifolds, short, somewhat triangular. The 2nd are flatish and look more like a traditional cat.

 

[Buck 5,000+ posts]

first ones are right off of the manifolds, short, somewhat triangular. The 2nd are flatish and look more like a traditional cat.

Yep, sweet.