Jmissle it sounds good. I would like to hear it in person to see how loud it really is. It sounds like it is louder than a stock mustang or camaro. I would almost say it sounds louder than or the same as a stock charger srt.

Good morning ponies
[youtube]http://www.youtube.com/watch?v=f-92RURtltE[/youtube]

http://www.youtube.com/watch?v=f-92RURtltE

jmissile that sounds great while driving but your neighbors must hate it the first few seconds after starting. That's a proper V8 tone in your driving videos though, the downshifts must initiate a lot of stoplight battles.

Altered wrote:jmissile that sounds great while driving but your neighbors must hate it the first few seconds after starting.

Yep I'm that guy lol. I don't care about my neighbors they all suck, I'm like

Jmissile that is bad sounding car. OMG I can't believe how good it sounds with just the resonators deleted and muffler delete. I can only imagine what it will sound like with x pipe and 2.5in piping

https://youtu.be/766bwEwnGwU


@DRM56, This is xpipe, 2.25 piping,resonator deletes,magnaflow competition mufflers.


And very nice jmissle. Sounds hella lovely.

Nice video @infinitedrift. Quick question. Are the mufflers welded in place of the resonators with just the tips put the back or did they put them in the normal spot with the quad tips welded to them? Just wondering.....

Normal spot with tips on the mufflers. Crv33 has them welded were the resonators used to be though.

I'm going to look into the custom x-pipe option instead of Stillen. Sounds like this will add more power along with better sounding exhaust. And it sounds much cheaper :-)

I'm still leaning towards the tried and tested (and properly R&D'ed) Stillen even if it's a little more money. It doesn't sound crazy...just the perfect mix.

I like the sound of the stillen, I just hate that they do nothing to get rid of the choke point in the exhaust system. That small collector kills our cars. Ot letting it breathe properly.

DRM56 wrote:I like the sound of the stillen, I just hate that they do nothing to get rid of the choke point in the exhaust system. That small collector kills our cars. Ot letting it breathe properly.

Yes it does! The 305 HP early model Titans had a bigger Y-pipe and it was still restrictive on those trucks. Nissan did away with the Y and went dual pipes to the muffler on the 317 HP trucks.

I mean they have to know that it's no good for our cars but yet they have done it for years. Maybe it's to keep sound down or something. Idk but I'm getting rid of my choke point very soon

Found this while trying to figure out which way to go on an exhaust upgrade....
https://www.youtube.com/watch?v=q3DH525v10o

Marosari00 that my M in that video. My buddy and I had a good time installing the stillen cat back and more fun making the video :-)

I have a question for those who know exhaust... I want to keep my stillen mufflers and resonators. But
However I am thinking of having the stillens cut right in front of the resonators and installing an x pipe between the resonators and the main cats which are attached to the factory headers. Is this a good plan i have and if it is where to I install the electric cutouts on this system ?
Also by doing this type of setup am I removing a secondary cat?
Any help is appreciated.

MpamP wrote:I have a question for those who know exhaust... I want to keep my stillen mufflers and resonators. But
However I am thinking of having the stillens cut right in front of the resonators and installing an x pipe between the resonators and the main cats which are attached to the factory headers. Is this a good plan i have and if it is where to I install the electric cutouts on this system ?
Also by doing this type of setup am I removing a secondary cat?
Any help is appreciated.

Nothing wrong with your plan. The "secondary cats" are actually part of the front Y-pipe assembly and removing them will not be an issue. There is no check engine light and you will pass an emissions test no problem. It will make your exhaust louder though. I run a 2-1/2" X-pipe coming off of the exhaust manifold/cat assembly with the OEM sport mufflers:


As far as cut outs, what are you looking to accomplish...performance gains or just more sound? Unless you run a custom tune, you won't get any performance gains over the Stillen exhaust. If anything, you'll lose performance. The stock ECU won't be able to adjust enough to take advantage of the increased exhaust flow. If you're looking for more sound, you can install them after the X-pipe, to take advantage of the balanced flow that the X-pipe provides and have a more refined sound. You can also install them before the X-pipe to achieve a more raw unrefined sound.

Power gains from intake and exhaust are easily noticeable even on stock tune on these engines. American racing headers claims 40 hp at the tires from their long tubes, high flow cats and exhaust on a QX56/Patrol/2017 Armada UNTUNED!

DFW2011M56S wrote:Power gains from intake and exhaust are easily noticeable even on stock tune on these engines. American racing headers claims 40 hp at the tires from their long tubes, high flow cats and exhaust on a QX56/Patrol/2017 Armada UNTUNED!

Depends on the extent of your intake and exhaust mods and what vehicles you are referring to. If I understood him right, MpamP stated that he was looking at replacing the post cats part of his front Y-pipe with an X-pipe and was looking at installing cutouts somewhere in between. Nothing was said about headers or intake mods; just the stock intake/exhaust manifolds and the Stillen catback exhaust with the resonators intact. I based my response on his post, nothing else.

I wasn't talking about the SUV/truck platform anyway; there are a lot more options for intake and exhaust mods for these vehicles, vs the VK56VD motors which as of right now don't lend themselves to many mods. I am not aware of any current production header/high flow cat options for the M56, and our intake mods are pretty much limited right now as well. I'm sure someone can build a set of headers for the VK56VD for a few grand, and maybe eventually R2C or someone else will come up with a viable CAI or RAI (after all, these motors just came out in 2011 so they are pretty new and it will take a while before some additional bolt on mods will be available)

In the meantime, with what is currently available for the M56 motor, I stand by my statement (again) that you will not see any significant performance gains by just adding a custom bolt on exhaust and/or custom intake unless you run a custom tune.

armybrat wrote:

DFW2011M56S wrote:Power gains from intake and exhaust are easily noticeable even on stock tune on these engines. American racing headers claims 40 hp at the tires from their long tubes, high flow cats and exhaust on a QX56/Patrol/2017 Armada UNTUNED!

Depends on the extent of your intake and exhaust mods and what vehicles you are referring to. If I understood him right, MpamP stated that he was looking at replacing the post cats part of his front Y-pipe with an X-pipe and was looking at installing cutouts somewhere in between. Nothing was said about headers or intake mods; just the stock intake/exhaust manifolds and the Stillen catback exhaust with the resonators intact. I based my response on his post, nothing else.

I wasn't talking about the SUV/truck platform anyway; there are a lot more options for intake and exhaust mods for these vehicles, vs the VK56VD motors which as of right now don't lend themselves to many mods. I am not aware of any current production header/high flow cat options for the M56, and our intake mods are pretty much limited right now as well. I'm sure someone can build a set of headers for the VK56VD for a few grand, and maybe eventually R2C or someone else will come up with a viable CAI or RAI (after all, these motors just came out in 2011 so they are pretty new and it will take a while before some additional bolt on mods will be available)

In the meantime, with what is currently available for the M56 motor, I stand by my statement (again) that you will not see any significant performance gains by just adding a custom bolt on exhaust and/or custom intake unless you run a custom tune.

You realize the platform I am talking about also runs the VK56VD???

That being said I picked up 20-25 hp and nearly 2 mph in the 1/8 deleting the post cats and adding a 2.5" X-pipe into the stock rear mufflers. I gain another 2.5 mph in the 1/8 with the cut-outs open. That is about a 40 hp gain with the stock exhaust manifolds and primary cats in place.

The HPS intake tubes and K&Ns work very well for me too.

I can also tell you that a $0.25 680 ohm 1/4 watt resistor was worth nearly 2 tenths in the 1/8 on a 95°F day. IAT based spark retard KILLS the performance of these cars.

DFW2011M56S wrote: ↑

Mon Sep 19, 2016 11:30 am

That being said I picked up 20-25 hp and nearly 2 mph in the 1/8 deleting the post cats and adding a 2.5" X-pipe into the stock rear mufflers. I gain another 2.5 mph in the 1/8 with the cut-outs open. That is about a 40 hp gain with the stock exhaust manifolds and primary cats in place.

The HPS intake tubes and K&Ns work very well for me too.

I can also tell you that a $0.25 680 ohm 1/4 watt resistor was worth nearly 2 tenths in the 1/8 on a 95°F day. IAT based spark retard KILLS the performance of these cars.

Don't take this the wrong way but I'm just gonna say what's on a lot of people's minds... "We don't believe you, you need more people"!!!

Data to back it up???

DFW2011M56S wrote: You realize the platform I am talking about also runs the VK56VD???

That being said I picked up 20-25 hp and nearly 2 mph in the 1/8 deleting the post cats and adding a 2.5" X-pipe into the stock rear mufflers. I gain another 2.5 mph in the 1/8 with the cut-outs open. That is about a 40 hp gain with the stock exhaust manifolds and primary cats in place.

The HPS intake tubes and K&Ns work very well for me too.

I can also tell you that a $0.25 680 ohm 1/4 watt resistor was worth nearly 2 tenths in the 1/8 on a 95°F day. IAT based spark retard KILLS the performance of these cars.

You are running the Bullydog GT Gas tuner so that is not a stock tune, which is what I was referring to. Yes I could see the gains then.

As far a running a resistor to keep more timing in (once again, not a stock tune), yeah you gain performance, but at what cost in the long run? You can accomplish the same thing with a custom tune without taking a chance on ruining your engine with detonation. Yes the timing is conservative but it's for a reason.

armybrat wrote:

DFW2011M56S wrote: You realize the platform I am talking about also runs the VK56VD???

That being said I picked up 20-25 hp and nearly 2 mph in the 1/8 deleting the post cats and adding a 2.5" X-pipe into the stock rear mufflers. I gain another 2.5 mph in the 1/8 with the cut-outs open. That is about a 40 hp gain with the stock exhaust manifolds and primary cats in place.

The HPS intake tubes and K&Ns work very well for me too.

I can also tell you that a $0.25 680 ohm 1/4 watt resistor was worth nearly 2 tenths in the 1/8 on a 95°F day. IAT based spark retard KILLS the performance of these cars.

You are running the Bullydog GT Gas tuner so that is not a stock tune, which is what I was referring to. Yes I could see the gains then.

As far a running a resistor to keep more timing in (once again, not a stock tune), yeah you gain performance, but at what cost in the long run? You can accomplish the same thing with a custom tune without taking a chance on ruining your engine with detonation. Yes the timing is conservative but it's for a reason.

I have run stock tune as well with the same mods and it still runs its a** off.

You will not see the gains I am talking about from Uprev because Uprev has not defined the IAT timing modification table. It is a fairly proven mod in the Titan world.

These are out of a GM LS1 ECM but our tables are fairly similar in nature. They are really over cautious with the retard vs temperature and the IAT heat soaks. You can make a full 1/4 mile pass and the IAT sensor will still be reading well above the actual incoming air temp.



There is also a Spark modifier table vs Coolant temp which is why a cooler thermostat helps these engines as well.

Ok thank everyone for the advice. I am thinking I will do the following:
2.5 x pipe header to stillen resonators. (Second cat delete)
Electric cutouts down stream of the "X" but before the stillen resonators. Assuming no fitment problems. I'll put them ahead of the "X" if need be.
Adding HPS intake tubes. (Need to buy these)
Adding Snow Performance H2O Methanol stage 2 kit. (Just need to install this)
Adding min 75 Shot nitrous no more than 150 (prob just 75)(need to buy this)

Now to find a competent muffler shop in the Houston Texas area... (Any recommendations)

Also if cut outs cause power/torque loss isn't the loss fairly small and in the lower RPM's only? Maybe the high rev gains would be enough to offset the low rev losses. Maybe I just get this thing on a dyno for some before and after data.

DFW2011M56S wrote: You will not see the gains I am talking about from Uprev because Uprev has not defined the IAT timing modification table. It is a fairly proven mod in the Titan world.

The forum member who I bought my X-pipe set up from posted a 1/4 mile time of 12.88 sec time @ 111.09 mph with Uprev. This is with a luxury sedan weighing 4200 lbs or so. That run is posted on Youtube with accompanying documentation. That was with no advanced timing change, 20" heavier wheels, and he was a big dude, 300 lbs IIRC. It is possible that Uprev may offer timing mods now, but I am not sure.

I am also looking at buying the HPS intake tubes, but I will stay with my modified panel filter set up for now. Then I will be ready for custom tuning, be it Uprev or other means.

With that said, you do make valid points and have my attention, so I am interested in how you documented your HP gains, and any documented 1/4 mile results, if you're willing to post them.

DFW2011M56S wrote:These are out of a GM LS1 ECM but our tables are fairly similar in nature. They are really over cautious with the retard vs temperature and the IAT heat soaks. You can make a full 1/4 mile pass and the IAT sensor will still be reading well above the actual incoming air temp.



There is also a Spark modifier table vs Coolant temp which is why a cooler thermostat helps these engines as well.

So I went back and read through some of your posts on the thread about taking the M to the dragstrip. A lot of good info and feedback. Sounds like two different ways of accomplishing the same thing...just need to decide which way to go. Thanks for your input!

TheMajesticKing wrote:Yes. You're not interfering with the emissions system by doing a muffler delete. However, the stock ypipe has cats built into it so technically a custom ypipe would not be smog compliant. BUT I just recently went through emissions here in MD and passed with no problems. There are 2 sets of cats (4 total) on the M56. The precats are located in the exhaust manifolds and they are VERY restrictive. So I couldn't see failing a smog check as long as those are still installed.
I have the custom ypipe now and there is no smoke or smell from my exhaust at all, and most importantly, no check engine light.

s***! My driver's side pre-cat decided to retire and Infiniti wants $2400 to rectify. Gosh darn it, I'm at 82k miles and long out of warranty! (

I'm sorry to hear that, maybe you should throw caution to the wind and get a set of custom headers made. Or maybe I'm confused on what the precat is. Anyhow sorry about the breakdown.

MpamP wrote:I'm sorry to hear that, maybe you should throw caution to the wind and get a set of custom headers made. Or maybe I'm confused on what the precat is. Anyhow sorry about the breakdown.

On the M56, the precats, or main cats, are actually made into the exhaust manifolds. They are flanged so that they bolt up to the secondary cats, which are made into the front Y-pipe assembly. If the main cat goes bad, you have to replace the whole exhaust manifold. E-store price is $844.83 plus $140 core charge for the part, plus installation. The driver's side (bank1) requires the engine to be pulled, which is why the repair is so expensive. Bank 2 manifold (passenger side) will be cheaper because it can be replaced without pulling the engine (RWD only)

russianbear54 wrote:

TheMajesticKing wrote:Yes. You're not interfering with the emissions system by doing a muffler delete. However, the stock ypipe has cats built into it so technically a custom ypipe would not be smog compliant. BUT I just recently went through emissions here in MD and passed with no problems. There are 2 sets of cats (4 total) on the M56. The precats are located in the exhaust manifolds and they are VERY restrictive. So I couldn't see failing a smog check as long as those are still installed.
I have the custom ypipe now and there is no smoke or smell from my exhaust at all, and most importantly, no check engine light.

s***! My driver's side pre-cat decided to retire and Infiniti wants $2400 to rectify. Gosh darn it, I'm at 82k miles and long out of warranty! (

That BLOWS dude! Is your car completely stock?