Quietest Boosted Exhaust?
 

So I've got Motordyne e370 shockwave exhaust and just put some Fast Intentions resonated test pipes in front of it. It sounds like it wants to kill someone at anything over 3500rpm.

In short, it's too damn loud for me. Plus as soon as TG's kit gets here I'll finish up my tune and will be moving even more air through so it's not going to get any quieter.

ART pipes won't really be any quieter but will be a lower tone so won't sound as crazy.

Or if I got Fast Intentions exhaust to out behind their pipes will that be quieter? I've only heard the FI exhaust once and that's on Cooltoys's ride which is NA so while it is a lot quieter than Motordyne but not exactly a fair comparison when Boost is added into the mix.

I could see about getting a third pair of resonators cut in I guess. Basically I have two sets if you count the Motordyne snot chambers, and then there is the central x-pipe muffler.

What are you guys running? I'd love to figure this out sooner than later and suggestions are more than welcome.

Thanks!

My Invidia seems pretty quiet.. I am noise averse as well unless I'm on it... Its only 60mm though so slightly undersized compared to the FI. It's also an OEM-style design so the pipes make sharp bends just before exit.

The FI test pipes are 2.5" and the Motordyne exhaust is 3". I guess being Canadian I should know how many mm that is but, well, lol

Holy crap the motordyne is 3"?!?!? That's crazy. I'll bet that is loud.

60mm ~ 2.36"

I have a full 3" AAM from the turbos back. Resonated Downpipes and true dual set up. It's quite enough to have a conversation while driving down the road at 80 and opens up when you get on it. Love the tone and volume. Zero complaints. I have one short video of how it sounds from inside the cabin with the windows down. Hope this helps !

https://youtu.be/0vK0HrwLx_4


Sent from my iPhone using Tapatalk

In the same boat right now mate.

I have Motordyne CBE, blew up Cats, installed TPs which ended up stuuupid loud, installed generic 200cpsi Cats near the back after the centre X-muffler, which helped but not enough.

This is a bigger issue for us with non-Turbo setups as Turbos naturally quieten down that noise.

Now it's killing me but I'm considering letting the Motordyne go for something else... I bought a 370 for this exhaust!

I had motordyne with art pipes, test pipes and HFC. I also had invidia with test pipe ad FI with test pipes. The invidia is the quietest than FI and motordyne is just stupid loud

And motordyne is way over priced

I got mine for an absolute steal years ago, brand new, so price isn't the issue.

Interesting you mention the Invidia, I was looking at it a few days ago and just yesterday I've started looking at the Injen one which seems even quieter, and I'd love to do the 'Quad' tips style like in this clip:

https://www.youtube.com/watch?v=7I5LvlwwVsE

Whatever I end up with, absolutely refuse to have any hiss or rasp... one of the big reasons I went Motordyne initially.

Let me put it this way.. motordyne with art pipes when na you still have hiss and a tad rasp and loud as Fock..
FI with test pipes has hiss. Invidia with test pipes no hiss or rasp and is in my opinion built way better than Motordyne. I have owned over 6 exhaust and my favorite are FI and Invidia.

With the Motordyne E370 & Test Pipes I currently have on, yes it's stupidly loud, but even louder due to the SC pushing way more volume of air through the system.

I don't have hiss, but I do have rasp now since ditching OEM Cats and going with Test Pipes.

I'm not a fan of the two Invidia mufflers on top of each other near the end, 'horizontal' if looking from the rear, how the exhaust has to make a 90deg turn to enter and like a 60deg to exit. May not be an issue in an NA application, but for an SC where you're looking for everyway to increase flow efficiency it just doesn't rub me the right way. At least Injen is more traditional with two standard 'inline' mufflers at the end.

Not sure yet about the Invidia, but the Injen exhaust is 60mm, which is like 2.36" or might as well be just 2.25", which should be a great help coming from the 3" Motordyne.

I'm not boosted but I can tell you my FI exhaust is quite a bit louder since the ECUTEK tune, so switching to FI might not help much. And I have stock cats and 12" resonators.

The AAM mentioned above sounds nice...

Stock cats will be by far the best sound dampener you will find. Unfortunately they will blow out on you with a sc.

I did some intense studies on this and can tell you first hand that, also unfortunately, the cnt exhaust with art pipes will be the quietest possible setup. The quality of the cnt is below average but the cost might off set that. I went to that after I got sick of the drone from my fi w/18" resonators. Yes, I'm getting old. Yes, it made it sound good to my old ***. It will rob you of a few hp but when your making over 500 that didn't matter as I enjoyed my car more than if I had my 5hp back.

That's the setup I will put on if I ever buy a Z or G again.

Research will tell you the same thing. The guy I sold my cnt to swapped it in for his fi also since he wanted a tamer sound. He hit me back saying it was perfect.

Also, you could go with a nismo can.

I had a CNT on my 2011 and I loved it =)
It is also a 60mm exhaust I believe, but is the higher flowing layout like HKS/FI/etc.

Dirt cheap too. Dayum...

CNT RACING 09-13 Nissan 370z Bolt on catback Exhaust system (non Nismo model) , 370 exhaust, 370z catback exhaust, 370 performance exhaust

I'd have one on my '13 too if it didn't already have an Invidia Gemini on it when I bought it.

I have the FI 3" exhaust and it is quite a bit quieter than motordyne or the FI 2.5". I it has a nice tone to it and when you get on the throttle it will open up nicely. You may also pick up a few whp with a 3" exhaust!

Sent from my SM-N910P using Tapatalk

You could simply quiet down the exhaust you have. Take a look at using side branch resonators, it really works and doesn't lower performance.
http://www.the370z.com/intake-exhaus...s-great-8.html

Do you have turbo or supercharger? If you have turbo, is it open dump wastegates? If so that is your issue as to why it's so loud.

Sent from my SM-G935T using Tapatalk

He is supercharged!

Sent from my SM-N910P using Tapatalk

Yes supercharged with an Si trim Vortech, so I'm moving some extra air. Also I'm waiting for TG's A/A kit to show up and air going in can affect the exhaust note a lot so I won't make any decisions until after that's on and see how it is.

But in any case the FI resonated test pipes and Motordyne combo is going to be WAY too loud for me. There is zero drone, rasp or anything like that, it's just the volume that is the issue.

I could also look st replacing the central Motordyne muffler 2@2.5in and 2@3.0out with something else, but then I really wouldn't know what kind of sound I'd end up with beforehand and then I'd be sort of stuck with it.

Love the motordyne exhaust and would hate to see it go but if that ends up being the answer then so be it. Quiet is more important to me right now.

Perhaps there is an armytrix type solution I can cut in as well for a bit more restriction for normal driving and can open the valve for the track. I'll have to look into that a bit further. Kind of the opposite of cutouts I guess lol

I have FI resonated test pipes and FI 18" resonated catback and the drone was getting to me so I added in side branch resonators which made it more bearable and made the exhaust quieter outside.

An option would be to restrict the airflow with small diameter pipes and resonated mufflers but that would probably raise temps and pressure.

I was actually thinking about switching over to Motordyne to eliminate the drone inside the cabin.

If you want to switch exhaust setups let me know.hahaha

I had the Motordyne resonated test pipes with the side branch resonators and the FI exhaust with 18" resonators and it still rattled my head.

The only way to do it is to add in additional mass in mufflers or downstream cats.

My old Comptech exhaust for my RSX had muffler tip inserts to quiet it down.

Looks like I'm going with Invidia. Can't seem to get a Injen into Australia for less than $2K AUD. Can get a local Invidia Q300 for $1.5K.

Absolutely gutted, but the Motordyne has to go. :(

That's a hard realization to come to. The Motordyne is so sweet. Think I'll try some downstream HFC before I make that call.

Those prices are crazy but I guess everything has to be shipped a long way to Oz so it gets expensive. At least you should get a solid return on the Motordyne, not that it's much consolation really.

Hope I can find a way to work with and keep mine. Not giving up just yet!

Already tried downstream HFCs, wasn't enough.

And yea, shipping alone was $550 USD... I'm asking for $1500 AUD, which will be exactly enough to effectively exchange it for the Invidia with no out of pocket loss, but still pissed I have to let the Motordyne go, because sure as **** I don't want to.

That $1.5 to $2K price tag is a hard pill to swallow. Id 100% be going with the CNT before that. It will be tame, cheap and decent quality. I didnt have any fitment issues.

I have the stillen sc with the stillen CBE and stillen's non res test pipes and its no where near as loud as some of the other set ups ive heard

I've got the FI 3" exhaust and they added a set of hfcs in the lead pipes. It's the perfect daily driver volume. It's almost a little too quiet now that the Z is a weekend toy, but the cats will come out with the next round of mods. Granted, I've got turbos to muffle the sound somewhat, so your setup with a SC might be perfect.

For quiet and cheap put back the stock or nismo axle back muffler.

Arguing opinions of sound levels online is always going to seem a little silly... but I am firmly in belief you just cannot have 3" system and an SC without a radical redesign if you want tolerable noise levels. Turbos affect that noise level a lot, not just somewhat.

Had a guy come by last night with Berk HFCs and Powerhouse Amuse1 CBE and he flipped out when I turned mine on and heard.... he thought his was pretty loud.

Are you kidding? Why not just give up and go back to NA then...

That is NOT a solution. -_-

Sorry for reading the OP's question.

Yeah, because basically choking the f*ck out of his boosted car is a legtimate solution...? :facepalm:

My experience.....

When my car was NA I installed the Fast Intentions CBE and the sound was great. Then I installed a Stillen SC kit and the sound got much louder. Next was a tune by Seb and again the sound changed, this time to a much lower and throaty sound.

Every change you do will affect the sound and level. I absolutely love the sound of my Z now!

Stock cats or test pipes?

And your solution of no solution is better. And just to educate you the muffler itself provides only a minor amount of restriction. I don't even think any list any gains from the axle back for the Z. It's the cats and small 2.25" dia piping from the exhaust headers down that significantly restrict flow. I doubt the loss would be greater than 1% which is not noticeable and you get a "quiet" car which is what was being asked.

I would think it sounds awesome too. I'm NA and recently was tuned. I was surprised at the difference in the exhaust sound. And I have stock cats.

How is the stock GTR exhaust so quiet? Seems you should be able to simulate that setup on a 370Z as well.

After reading through the comments again there are not a lot of options that will look pleasing to the eye trying to cut down the noise coming out the exhaust do to the restrictions that start out of the manifold. When you add a supercharger or a twin turbo you are pushing a lot more air through the system and the restrictions will cause an increase in sound and can cause performance issues due scavenging. A 3" down pipe is needed to benefit a 3" exhaust system. This will significantly cut down on the sound. The Motordyne exhaust only becomes 3" where it meets up with the connection to the y pipe so the sound is actually magnified. I have had the pleasure of riding in a Z that had a twin SC and a Motordyne exhaust system on it. Yeah she was loud and sexy as hell. I doubt there going to any other exhaust will change anything significant because of the amount of air moving through the system. Yes, I think maybe a system like Armytrix might help to a degree but that is an expensive option that may be a fail. I would suggest having a baffle or butterfly value put in that can be manually turned on or off.

Sent from my SM-N910P using Tapatalk