Deleting cats... Can O2 sensors be fooled?

[magimerlin]

Cats take a lot of definition out of the exhaust. I've hit a cam, and I like to hear it.

I would also assume you've never seen the honeycomb inside of a cat. Exhaust getting through is like trying to pour water through a concrete filter.



A y pipe will have the same effect.

~Via Mobile \,,/

Never "Ass U ME"........lol I have seen plenty of them and installed and removed plenty of them in my lifetime.. getting ready to install a 3" high flow flowmaster one on my rig tomorrow actually along with a new muffler.. If you wanna hear your exhaust that's fine, I like to hear mine to, I think we all do, its a curse....lol.... But in the end do what you personally like. After all its your rig, your time, your money..... And Yes a cat can and does change the sound of most all systems.


From my experiences and research...
A Y-pipe does not have the same effect of a proper h-pipe/cross over pipe or x-pipe. With a y-pipe both banks will hit at the y. If one compression stroke is stronger then the other it will push its way through bottle necking the other adjacent firing cylinder. i.e. incomplete burn and or not running as efficient and strong as it could..

An h-pipe or cross over pipe or even better an x-pipe, in a duel exhaust set up will allow it to fully expel the gasses from both banks in a more efficient even manor. Letting all the gasses out of the cylinder on each stroke/compression faster and more evenly, with out pushing one back or putting one partly on hold if you will, will allow a faster cleaner burn to continue on each firing of the cylinder.

This is of course only comparable and valid comparison with each systems having the same pipe size as each other. Pipe size will play a major role in the way that each style will perform.

Not a challenge but...but this is how i think/work.. If I am wrong show me that I am wrong, and show me the correct way or proven info so that I may learn the correct or right way.. I am always willing to admit when I wrong with no issue. My info comes from working on many types of vehicles for the last 20 or so years. OK now I feel old...thanks.....lol Not professionally mind you...lol

Sorry Airman didn't mean to steel your thread....

 

[magimerlin]

SO, can I Y pipe my small duals into this 3" single with flowmaster? Would it run right?

Yes it would run fine.. running your duels into a single 3" is just basically making a larger y-pipe... You should be fine..

 

[VorTecxas]

What year were they? TBI trucks only came with a pre-cat sensor.

~Via Mobile \,,/

Yes, Im aware of that. Ive only owned Vortecs but have worked on plenty of TBIs

 

[VorTecxas]

I've toyed with the idea of removing my cats but now I'm hearing rumors of TX doing emissions testing and that cats would become something that they inspect.

We already have had emissions testing for a long time in some northern counties. Cats are part of the inspection, but are rarely checked as long as the MIL isnt on.

 

[VorTecxas]

When you next get the PCM tuned, have them turn off error reporting related to cat efficiency. It's simple simon easy to do. This effectively renders the rear O2 sensors useless. You still need the fronts for fuel trimming.

If you pop the O2's out after this, don't throw them away. They are still good and the same ones as the front sensors making them decent spares.

Be warned though: if you ever move to a state with emissions testing, you're hooped....

The plugs are different for front and rear...

 

[VorTecxas]

Never "Ass U ME"........lol I have seen plenty of them and installed and removed plenty of them in my lifetime.. getting ready to install a 3" high flow flowmaster one on my rig tomorrow actually along with a new muffler.. If you wanna hear your exhaust that's fine, I like to hear mine to, I think we all do, its a curse....lol.... But in the end do what you personally like. After all its your rig, your time, your money..... And Yes a cat can and does change the sound of most all systems.


From my experiences and research...
A Y-pipe does not have the same effect of a proper h-pipe/cross over pipe or x-pipe. With a y-pipe both banks will hit at the y. If one compression stroke is stronger then the other it will push its way through bottle necking the other adjacent firing cylinder. i.e. incomplete burn and or not running as efficient and strong as it could..

An h-pipe or cross over pipe or even better an x-pipe, in a duel exhaust set up will allow it to fully expel the gasses from both banks in a more efficient even manor. Letting all the gasses out of the cylinder on each stroke/compression faster and more evenly, with out pushing one back or putting one partly on hold if you will, will allow a faster cleaner burn to continue on each firing of the cylinder.

This is of course only comparable and valid comparison with each systems having the same pipe size as each other. Pipe size will play a major role in the way that each style will perform.

Not a challenge but...but this is how i think/work.. If I am wrong show me that I am wrong, and show me the correct way or proven info so that I may learn the correct or right way.. I am always willing to admit when I wrong with no issue. My info comes from working on many types of vehicles for the last 20 or so years. OK now I feel old...thanks.....lol Not professionally mind you...lol

Sorry Airman didn't mean to steel your thread....

Well said sir

 

[baddbradd]

My rear o2's are hanging zip tied by my transmission....................No mil

 

[AirmanSkee]

Will my truck run bad with the O2s not in, or will I just have the light? Because I have the light always anyways because I have a different PCM in mine anyways.

 

[magimerlin]

It may not run totally right with them just missing. Don't really have that much experience on 4 O2 in the exhaust. I'm use to just one or two upstream and no down streams. If you are going to be welding anyways... At most parts stores in their paper catalogs for the exhausts you can find just the O2 weld in bung. It's usually near the back of the catalog. Usually like 5-8 bucks each.


Sent from what use to be a great country.

 

[AirmanSkee]

Yeah I am just going to get the bungs and weld em in. Or use the bungs in my exhaust now and put them in the 3". Not going to be a big deal, I'll figure it out now. I got my questions answered! Thanks guys.