[1tirefire]

I have an 07, from sifting through a sea of threads it seems the general agreement seems to be that my 07 2wd should have flow through resonators after my primary cats. Well while removing my exhaust up to the supposed "resonators" I find theyre not free flow, they have a honeycomb barrier inside of them. So....what are they?!?, cats or resonators? Either way, they're getting tampered with!! If they're cats can I gut them without failing Texas emission testing? If they are cats, I wanna gut em, if they're resonators, I'm gonna delete em, there's an o2 sensor in front of em, but not behind em. What's the deal???

 

[cayers1122]

They are pointless. I removed the secondaries all together on my truck and it passed emissions just fine.

 

[O-FiveCC]

They are cats...04-06 2wd Titans are the only Titans with resonators...04-06 4wd and all 2007+ Titans have 4 cats.

 

[O-FiveCC]

You can gut them. Or you can buy some straight through "Walker Direct Fit B-pipes". No you will not fail inspection. I mean 04-06 2wd Titans did not have cats in that location, so there is no need for them. You will pass inspection and will not get any check engine light, as you mentioned the sensor is in front of them, so nothing reads after those second set of cats

 

[1tirefire]

Cool, that's what I was hopin to hear. The way I've got it now, I've taken all the cat back exhaust off. It stops at the rear cats, while giving throttle I can hear like a tick/hiss sound comin from the pass side. I thought it was just vibration at first. Then I got the few things that could've been vibrating out of the cab, it's still there. I'm used to old cast iron engines that you can run straight headers and not worry bout nothin but gettin a noise pollution ticket. Not sure if runnin the exhaust in this way until I can get it setup the way I want will be detrimental to my engine...any input on this guys? I really hope it won't hurt cause Im likin the way it sounds, lol.

 

[Stock '06]

First off i have 4 cats and the resonators on my 06. The local shop here that i use said the 2 rear cats can be removed and you will still pass inspection but... and there is always a but, you might have high levels on your truck. Find a shop that you can trust and talk with them.

 

[O-FiveCC]

You do not have 4 cats and 2 resonators. If so, you have one of a kind Titan

 

[Stock '06]

You do not have 4 cats and 2 resonators. If so, you have one of a kind Titan

Thanks for letting me know what i have on my truck. I guess all the years that I spent in college didnt pay off. Nor the years of taking A.S.E certs.
I do have 4 cats, I have one coming down at at manifold and one on each pipe in front of my resonators.

 

[O-FiveCC]

I'll tell you again, you do not have 4 cats and 2 resonators like I said. You may have 4 cats, and you may have 2 cats and 2 resonators.

First off i have 4 cats and the resonators on my 06

I'm not worried about your ASE certification, as I know more about these trucks then you do until you've studied this truck and its exhaust, intake and performance for a good 3+ years. I will say it again, since apparently, you went to school for your ASE thingy, and not comprehension. You either have 4 cats or you have 2 cats and 2 resonators...Unless you modified your truck. If you have the big round cans in your b-pipes, then you have cats, if you have the smaller casing in your b-pipes, then you have resonators. If you are a 4x4, then you have 4 cats, if you are 4x2, then you have 2 cats and 2 resonators. Although, there was a handful of people with 2wd (04-06) who actually had cats in place of the resonator, and some 4x4's who had resonators in place of cats. You have a cat on the manifold, and either a resonator OR cat in the following b-pipe

Show me pics of your 4 cats and 2 resonators.

 

[04GreenT]

I know for a fact that my 04 2wd has(had) the cats on the manifolds and resos on the b pipes. After the long tubes it obviously doesn't have the front cats.

With the long tubes and stock exhaust besides an 18" maggy dumped right after the muffler my truck is loud and raspy when I get on it but its very reasonable under light throttle and idling. I will probably replace the stock resos with bullets when I do a new ypipe and all that good stuff.

 

[O-FiveCC]

Yeah its funny, there was a handful of guys like you who had cats where most had resonators and vice versa. I remember a few other members with 4x4 saying they had resonators. Not sure why Nissan did that lol.

 

[1tirefire]

So, I've got my cat back completely removed in prep for new exhaust, runnin cat forward only. Haven't gutted my rear cats yet, gonna wait for install day. Gettin a tick or hiss from the passenger side, can running this way damage anything?

 

[O-FiveCC]

So you are running with no exhaust? Only thing I can think of, would be to check what is near where the exhaust gas will be exiting. Are there any wires or anything that is prone to heat damage anywhere around where the exhaust is exiting?

 

[1tirefire]

Yea, and it sounds F'n awesome, lol. It's only on an extremely short term basis, I'm tryin to keep from runnin it as much as possible. I've checked all the wires/lines that are n e where close, there's really nothing. On the drivers side the gas tank is bout 2 1/2 - 3 ft away, covered in heat shields. I'm just wondering about the lack of backpressure, possibly messing something up. I do know that that sucker wants to RUN!! From bout 60 mph there's alot more acceleration!

 

[smiller51283]

I'll tell you again, you do not have 4 cats and 2 resonators like I said. You may have 4 cats, and you may have 2 cats and 2 resonators.

I'm not worried about your ASE certification, as I know more about these trucks then you do until you've studied this truck and its exhaust, intake and performance for a good 3+ years. I will say it again, since apparently, you went to school for your ASE thingy, and not comprehension. You either have 4 cats or you have 2 cats and 2 resonators...Unless you modified your truck. If you have the big round cans in your b-pipes, then you have cats, if you have the smaller casing in your b-pipes, then you have resonators. If you are a 4x4, then you have 4 cats, if you are 4x2, then you have 2 cats and 2 resonators. Although, there was a handful of people with 2wd (04-06) who actually had cats in place of the resonator, and some 4x4's who had resonators in place of cats. You have a cat on the manifold, and either a resonator OR cat in the following b-pipe

Show me pics of your 4 cats and 2 resonators.

So does he have a cert for Nissan Titan exhaust?

I love how people that went to school and have certs think they are experts at all things automotive. I think the most skilled people I have ever met at anything automotive were never formally trained.

 

[bj2007]

sounds like a tool lol

 

[1tirefire]

Well, gutted my rear cats today, was amazed at how much crap came out of em!! Runnin without mufflers, that thing is LOUD!! Sounds good at low throttle, not so much once you give it some pedal. I'm wantin to know what kind of muffler/pipe setup I can run to get rid of that god awful poppin I get when it gets some throttle. Any ideas???

 

[LandShark]

Well, gutted my rear cats today, was amazed at how much crap came out of em!! Runnin without mufflers, that thing is LOUD!! Sounds good at low throttle, not so much once you give it some pedal. I'm wantin to know what kind of muffler/pipe setup I can run to get rid of that god awful poppin I get when it gets some throttle. Any ideas???

Flow master Y-pipe, 3" pipe to a hooker aerochamber center in/center out or a 22" magna flow then dump it.

 

[Shipwrech]

OK, I am poking and prying for some more info. I just replaced everything from my Y collector to my tailpipes and I installed a Volant CAI. I am getting my UpRev tomorrow and i am looking for all the HP I can get after this without paying too much more money.

Exactly HOW MUCH louder will my T be after I gut the cats and are we talking about 1-5 HP?

Oh I have a 04 4x4 CC and I am no certified ASE tech and i am sure I have 4 cats.

 

[O-FiveCC]

Gutting the cats give you about 1/2 the gain of headers. I'm thinking more around 10-15whp. I went form stock manfiolds/cats, to LT headers, and no cats, to OEM manifolds and no cats. The OEM manifolds w/o cats performed a good deal better then OEM with cats. I could feel some soft spots where the LT headers performed better obviously, but I was surprised at how well it did. It will be a bit louder with no cats, I don't know how to explain it. Its almost as loud as LT headers and no cats, but just not as deep sounding