exhaust question..

[MarkSheriff]

i believe the more aggressive the sound is, the more drone you will get.

i have the two cats, then the two stock resonators, then a flowmaster super 44 muffler replaced the stock muffler and the tailpipe resonator has been taken off. 4" muffler tip to finish the job

zero rasp, and a mean sounding truck (link to video posted earlier in this thread))
there is a good amount of drone, which will be taken care of because i will be sound deadening the trunk due to my sound system, so that should take care of some drone because most of the noise comes from the trunk lid area.

[smj999smj]

i believe the more aggressive the sound is, the more drone you will get.

i have the two cats, then the two stock resonators, then a flowmaster super 44 muffler replaced the stock muffler and the tailpipe resonator has been taken off. 4" muffler tip to finish the job

zero rasp, and a mean sounding truck (link to video posted earlier in this thread))
there is a good amount of drone, which will be taken care of because i will be sound deadening the trunk due to my sound system, so that should take care of some drone because most of the noise comes from the trunk lid area.

Those aren't resonators, albeit they look like it and Walker refers to them as such. They are actually catalytic converters, as well.

[MarkSheriff]

I really belive those are resonators after our cats.
Cats have oxygen sensors before and after them to measure oxygen before and after the cats.
You will see that before and after the resonators (after the cats) do not have oxygen sensors

If you belive the resonators are cats, then how will the computer know if the fuel mixture is burning rich or lean if there are no o2 sensors measuring before and after the so called cats

[NmexMAX]

I really belive those are resonators after our cats.
Cats have oxygen sensors before and after them to measure oxygen before and after the cats.
You will see that before and after the resonators (after the cats) do not have oxygen sensors

If you belive the resonators are cats, then how will the computer know if the fuel mixture is burning rich or lean if there are no o2 sensors measuring before and after the so called cats

They are cats, I've seen them. But they have no monitoring on them. I replaced my cats/b-pipes for Cajun cat-less B-pipes. You can get those Cajun pipes w/cats, but I opted out since they do not have any monitoring on them, I have no SES.


http://www.titantalk.com/forums/titan-p ... -flow.html

[MarkSheriff]

Hmm thats weird and confusing. No 02 sensors and no monitoring, yet its present in the exhaust system. Why did nissan do this? Maybe as an extra clean emissions thing? Or maybe extra sound reduction? Kinda want to email nissan and really find out.

I have some questions for you guys who know much or have done it:
I hear that the y pipe on our pathys are not so good and it would be better to have a dual in muffler with single or dual out? Is this true?

Also how important is back pressure on our pathys? Do we need some restriction in our exhaust for good backpressure? Does it affect torque?

Right now my exhaust setup is as folows:
Cats-secondary cats (or resonators)-y pipe-flowmaster super 44muffler-tailpipe-exhaust tip

Is it best to remove the y pipe and have a dual in muffler with dual out or single out?

I have already reomved the little resonator/extra muffler at the tailpipe and only have an exhaust tip on the tailpipe. Any gains on removing the secondary cats also?

[NmexMAX]

Hmm thats weird and confusing. No 02 sensors and no monitoring, yet its present in the exhaust system. Why did nissan do this? Maybe as an extra clean emissions thing? Or maybe extra sound reduction? Kinda want to email nissan and really find out.

Same thing in my 2003 Maxima. The 2 precats hav monitoring, but the main cat under the car does not. But 95-99 Maximas have monitoring even after the main cat under the car. And also, the Pathy does have monitoring on it’s pre-cats on/in the manifolds, but not on the secondary cats.

I have some questions for you guys who know much or have done it:
I hear that the y pipe on our pathys are not so good and it would be better to have a dual in muffler with single or dual out? Is this true?

It was just V8 Pathy’s that use dual inlet vs single like the V6.


V8



V6


Second to the last post for real pics:
http://www.thenissanpath.com/viewtopic. ... 28d28628d3

And here’s an idea:
http://www.thenissanpath.com/viewtopic. ... 5bbc1a1580

Right now my exhaust setup is as folows:
Cats-secondary cats (or resonators)-y pipe-flowmaster super 44muffler-tailpipe-exhaust tip

Is it best to remove the y pipe and have a dual in muffler with dual out or single out?

I have already reomved the little resonator/extra muffler at the tailpipe and only have an exhaust tip on the tailpipe. Any gains on removing the secondary cats also?

V8 titans and Armada’s gain quite a bit with just an MF (18 or 22” muffler) in addition to the b-pipes. Not sure the rear mini-muffler would do anything, mine Is still there since it’s a bit on the loud side as it is. Since they’re not monitored, I’d go ahead and remove them unless you were going with longutbes of some sort, then I would leave them for sound control .

[MarkSheriff]

thanks for the visuals and the help, so would you say it would be good to get rid of my y pipe and just use a dual in muffler? i currently have a single in single out flowmaster but what i could do is get a dual in dual out and have dual tailpipes at the back since i removed my spare tire as well, no?

[XVTer]

Yes, you definitely want to have a tailpipe resonator or it will sound "raspy."

I have doug Thornley long tubes, b pipes and Gibson cat back, the "rasp" was awful so I pulled the b pipes and put the stock rear cats back in which helped the "rasp" it's still there but not nearly as bad. But I still don't care for the drone of the Gibson muffler. My question is how much better is the magnaflow in terms of overall drone and quietness? At this point I'm looking for something that is nice and quiet under normal conditions with some growl under full throttle. Also who would you recommend for aftermarket resonator?

Funny as I had the same experience with the gibson - almost sounded ricey. I switched back to stock and craigslisted the cat-back. The combination I liked best on my Xterra was the stock manifolds/primary cats, deleted secondary cats and borla muffler. I had a super 44 for a year or two but it rotted off; went all stainless after that with the Borla

[smj999smj]

The upstream cats are three-way catalyst and the downstream cats are two-way catalyst. The fronts are monitored and the rears are not. There really is not reason to monitor the rear converters because the front converters do most of the job of converting exhaust emissions.

[MarkSheriff]

Have most of you gotten rid of the y pipe and use dual in mufflers instead?

[smj999smj]

If one is replacing the muffler, then it makes sense to go with a two inlet style muffler. Some have kept the stock muffler, but have just eliminated the restrictive "pipe sandwich" at the front of the muffler that came out of the factory and installed what would seem to be a more efficient "Y" fitting. Magnaflow is one company I know that makes the "Y" fitting. How much benefit over the stock design one achieves by doing this, I don't know. I haven't seen any definitive proof as to increase in performance, such as dyno results or track times. It definitely "looks" like it would be better.

[unreal2k1]

So I read all the comments on here and after 230k miles on the 05 Pathy it needed everything from the main cats back. From Nissan it was going to cost over 2.2k. Since my wife drives this around town and most of the time I did not want to make it to loud for her. So i went ahead and got the original muffler, cross pipe, and tail pipe from Nissan and the secondary cat or resonator. which by the way has a core charge from Nissan if you buy it. Which is a cat cuz they want the materials back from it. I got the straight pipes from the link in the previous posts and at $169 delivered in 2 days to NY that was great. Everything installed it is actually louder than expected. virtually silent when cruising but you notice it on the throttle instantly. and when first started. Amazon has Eastern cat versions for $142 a piece so if the sound is not quieter as the new pipes wear in after a couple of weeks, I will have to get those and install them. Just thought I would share my results on this. I always buy from courtesy parts in texas but I did not want to pay the shipping and how long it takes from them to NY via ground. I tried these guys on ebay who is a nissan dealer in Mass.
http://www.ebay.com/itm/NISSAN-20030EA2 ... 98?vxp=mtr

The pipes came from here which is listed for the frontier
http://www.lmperformance.com/572437
but fits perfect. Just want to say thank you to all the info from all the members on here its a great help

[selliott]

I ended up pulling the gibson off and trying walkers "stock replacement" so far its nice and quiet and only cost me $280 for the cat back we will see how well it holds up