What causes exhaust drone ?

Exhaust modifications

What causes exhaust drone ?

Postby scottb721 » Wed Oct 23, 2013 12:54 pm

I'm about to have my rear mufflers replaced for some extra sound out of the car.
Couple of quotes I've received are-
1. a pair of Hitech stainless steel dual tip mufflers $980
2. Cat back X-Force SS $850 or mild steel $475 (single tips I presume but I'd prefer duals. I'm not keen either on what some have said are 4" tips on their x-force)

I've read several times of x-force owners mention drone on the highway.
Would this be the result of the centre muffler being changed as part of the cat-back package ?

On my last Lib, an 03 2.5, I had just the rear muffler changed to a 'sports' one and it was great.

Would leaving the centre muffler stock reduce the likelihood of droning noise on the highway ?
I'd like to do this right the first time.

Thank you.
08 3.0 spec B
User avatar
scottb721
 
Posts: 170
Joined: Wed Feb 06, 2008 8:39 pm
Location: Nelson Bay / Newcastle NSW
Car: 2008 3.0R spec B auto sedan
Real name: Scott

Re: What causes exhaust drone ?

Postby SIMBAT » Wed Oct 23, 2013 3:05 pm

The stock centre muffler cuts out most of the droning if you just replace mufflers to sports mufflers you wont have drone issues, but as soon as you take out or change the centre muffler it will drone so much on acceleration and deceleration, you be praying for flat roads and flowing traffic all the time.

my opinion for you is for you to get some nice universal twin tip sports mufflers, (x force ones are great) get them made up to connect to the existing muffler flanges and you will have a great note and noticeable volume from out side the car and in the car i think you'll find there will be a perfect increase in exhaust note which will compliment the engine noises.

If you want it a little bit more aggressive than that i suggest getting your exhaust shop to put a flange join immediately after the centre muffler (i cant remember if there is one already) and he might as well put one on your stock set up so you can bolt it back on whenever you want. then from that flange go 3.5" to the Y pipes, then into 2" up to the flange for your sports mufflers. this will increase flow and give the exhaust a more aggressive/throatier tone without making it noticeably dronier. You can go mild steel or stainless depending on your budget and it would be probably cheaper than a cat back system.

For me i wanted it loud and unrestricted because i do occasional track days so I have just deleted my mufflers and had straight pipes made up with a flange so i can bolt on or off my mufflers whenever i want, it drones a fair bit but not intolerable.
my12 VW Tiguan TDI-tuned
my16 Hyper Blue WRX STI
my16 Honda Jazz VTI
User avatar
SIMBAT
 
Posts: 422
Joined: Tue Sep 18, 2012 8:14 pm
Location: north east Melbourne suburbs
Real name: the dream tiger

Re: What causes exhaust drone ?

Postby Smithy » Wed Oct 23, 2013 3:40 pm

Would highly suggest and recommend xforce Y pipe into TCP Auto Quad tip mufflers.

I get a little drone under load at lowish RPM, besides that she's all gravy! 8) Unfortunately 'drone' is all up to the owner though. I've got some friends cars who I think drone horribly but they don't seem to care/notice.

http://www.youtube.com/watch?v=t49GO9f6jB8
http://www.youtube.com/watch?v=VEvMdThhx70

Those video's are when the pipes were freshly installed and new (0-2 days old), it's slightly louder now.

Sorry for not answering your question properly however, I just came to preach the good word of the TCP :P
Smithy
 
Posts: 174
Joined: Mon Jan 02, 2012 8:00 pm
Location: SE Melbourne
Car: 2005 3.0R-B
Real name: Chris

Re: What causes exhaust drone ?

Postby Kekotic » Wed Oct 23, 2013 5:48 pm

Smithy wrote:Would highly suggest and recommend xforce Y pipe into TCP Auto Quad tip mufflers.

A few people (albeit with TCP TBE systems) ended up selling them because the drone was unbearable. They all had one thing in common, they had auto transmissions. I wouldn't recommend TCP/xforce to someone if their main concern is drone.

Scott the Hitechs sound great on their own on a 3.0, although for $1000 it's pretty steep. Second hand would be ideal if you can wait around for a while.
User avatar
Kekotic
-stickered-
 
Posts: 6436
Joined: Tue Jun 08, 2010 6:46 pm
Car: MY07 Liberty GT Spec.B
Real name: Kieran
Profile URL: viewtopic.php?f=10&t=13066

What causes exhaust drone ?

Postby ndlibgt » Wed Oct 23, 2013 7:37 pm

My setup consisted of Tcp muffs, had a mid pipe 3" into 2.5" custom made by Barney from Hallam performance and phat dump on my auto with zero drone. Key is the muffler in the mid pipe IMO.
User avatar
ndlibgt
 
Posts: 342
Joined: Sat Mar 26, 2011 6:57 am
Location: Melbourne
Car: 04 GT
Real name: Nelson

Re: What causes exhaust drone ?

Postby scottb721 » Wed Oct 23, 2013 9:35 pm

I might go and talk to a couple of the x-force installers tomorrow as I'll be near enough to make the trip worthwhile. They might even suggest other brands.

I'm really not interested in having it done all the way up to the cat and and after reading the input here I will definitely leave the centre one stock.
I'd love the Hi-techs and money isn't really an issue however if I can save some I may as well plus it's a 3hr drive to Hi-tech.

Thanks
08 3.0 spec B
User avatar
scottb721
 
Posts: 170
Joined: Wed Feb 06, 2008 8:39 pm
Location: Nelson Bay / Newcastle NSW
Car: 2008 3.0R spec B auto sedan
Real name: Scott

Re: What causes exhaust drone ?

Postby chanham » Wed Oct 23, 2013 11:23 pm

Smithy wrote: Unfortunately 'drone' is all up to the owner though. I've got some friends cars who I think drone horribly but they don't seem to care/notice.


this.

I think it's dependant on the owner. What sounds shit to some may sound fine to others.

I'm running ultrex quads and a xforce y + center pipe all in stainless on my 3.0. When at speed, its a very SLIGHT 'hummm' drone, but its absolutely bearable. You only realy notice when you pay attention to it. When putting more load on the pedal to get up to speed, its a tad more droney, but it doesn't bother me too much!
User avatar
chanham
formerly ciand06
 
Posts: 593
Joined: Mon May 28, 2012 12:18 am
Location: Perth, Western Australia
Car: Subaru Liberty 3.0R 2004
Profile URL: viewtopic.php?f=10&t=18831

Re: What causes exhaust drone ?

Postby chanham » Wed Oct 23, 2013 11:27 pm

But in my opinion its totally worth doing to really hear the h6 sing!
User avatar
chanham
formerly ciand06
 
Posts: 593
Joined: Mon May 28, 2012 12:18 am
Location: Perth, Western Australia
Car: Subaru Liberty 3.0R 2004
Profile URL: viewtopic.php?f=10&t=18831

Re: What causes exhaust drone ?

Postby alexeiwoody » Thu Oct 24, 2013 7:27 am

Drone is when at certain rpm, usually 2000-3000, the exhaust is louder inside the car than it is outside. If it's not annoying the hell out of you, then it's not drone. You won't get it by just changing mufflers.

If you decide to do the whole catback - drone is caused by not having a middle muffler. Aftermarket systems usually only have a 'resonator' in the centre pipe, which doesn't do squat. Put a straight through muffler in there and no drone even with a full 3" TCP tbe. Tcp quads sound good, look the same but cost a lot less than hi techs. No need to waste money or driving :) Goodluck
Running no. of weeks without breaking something in the lib: 0
No. of things still to fix in in the lib: 43
User avatar
alexeiwoody
 
Posts: 1894
Joined: Thu Jul 12, 2012 11:47 pm
Location: Melbourne
Car: MY07 LibGT 5EAT
Real name: Alexei

Re: What causes exhaust drone ?

Postby scottb721 » Thu Oct 24, 2013 12:34 pm

Went to a couple of joints in Newy. $500 for a pair of X-force rears in stainless plus $150 for different tips. They're 1-2 Y tips look too long though, and wide probably.
Another tip option I'd be happy with are the double tapered ovals. These follow the bumper curved both horizontally and vertically.

If the TCPs are a simple bolt-on job I'll see how much they are shipped. I've had mine off before.
Are the TCP genuine duals or just Y tips ?

Cheers all
08 3.0 spec B
User avatar
scottb721
 
Posts: 170
Joined: Wed Feb 06, 2008 8:39 pm
Location: Nelson Bay / Newcastle NSW
Car: 2008 3.0R spec B auto sedan
Real name: Scott

Re: What causes exhaust drone ?

Postby alexeiwoody » Thu Oct 24, 2013 12:59 pm

scottb721 wrote:Went to a couple of joints in Newy. $500 for a pair of X-force rears in stainless plus $150 for different tips. They're 1-2 Y tips look too long though, and wide probably.
Another tip option I'd be happy with are the double tapered ovals. These follow the bumper curved both horizontally and vertically.

If the TCPs are a simple bolt-on job I'll see how much they are shipped. I've had mine off before.
Are the TCP genuine duals or just Y tips ?

Cheers all


The tcp are proper quad tips and look nice like a factory exhaust should, performance but stylish. Same as hi techs. The x force are probably the more obnoxious ones out there, although you can't fault their performance exhaust systems.

The tcp and the hi techs and the phat quads are all made for the lib so they'll bolt on nicely onto stock pipes. The trick with any brand quads is to try and get the quad tips to align properly, so it looks like sex and not like an aftermarket botch job.
Running no. of weeks without breaking something in the lib: 0
No. of things still to fix in in the lib: 43
User avatar
alexeiwoody
 
Posts: 1894
Joined: Thu Jul 12, 2012 11:47 pm
Location: Melbourne
Car: MY07 LibGT 5EAT
Real name: Alexei

Re: What causes exhaust drone ?

Postby scottb721 » Thu Oct 24, 2013 1:31 pm

alexeiwoody wrote:
scottb721 wrote: The trick with any brand quads is to try and get the quad tips to align properly.


Is this problem negated by going to something like the TCPs that bolt straight in ?
08 3.0 spec B
User avatar
scottb721
 
Posts: 170
Joined: Wed Feb 06, 2008 8:39 pm
Location: Nelson Bay / Newcastle NSW
Car: 2008 3.0R spec B auto sedan
Real name: Scott

Re: What causes exhaust drone ?

Postby shav » Thu Oct 24, 2013 3:23 pm

Is the centre pipe in a stock exhaust system restrictive? If you were to replace just the mid and Y piece with a 3" mild steel system and 'better' flowing centre pipe, and kept the stock mufflers, would there be drone as well as a performance increase once tuned?
Cheers
Shav

MY07 Subaru Liberty GT Premium Sedan | HKS Panel filter | Pierburg 3 port | Whiteline adj sways F&R | Cusco HD mounts | Whiteline HD front sway links | Anycarlink AL-1080B | Ultrex s/s 3" CBE | Ultrex PU lip spoiler | Invidia s/s dump pipe and 100cel cat | KiDo tuned | DBA T2 rotors | Intima SS brake pads | Mishimoto TMIC | Koya ISR7 wheels | 265L Kobe fuel pump | Diamond Works SI Drive dial | Bilsteins

COSMETIC MODS ON THE WAY

My other toys:
2012 Focus Cayo 2.0 road bike
2015 Cervelo S5 VWD road bike
User avatar
shav
 
Posts: 3602
Joined: Tue Jun 26, 2012 12:01 pm
Location: Adelaide, Southern Suburbs
Car: MY07 Subaru Liberty GT Premium
Real name: Shav
Profile URL: viewtopic.php?f=10&t=18915&start=480

Re: What causes exhaust drone ?

Postby alexeiwoody » Thu Oct 24, 2013 9:59 pm

The stock mufflers are massive compared to most aftermarket brands, shouldn't have any drone.

Regarding alignment, might be good with any of the top brands, just something to be aware of if you're DIY. The reason I brought it up is quad tips make even slight crookedness apparent.

You better post some pics up so we can all scrutinise and if it's bad - laugh? :D Nah, just kidding the mufflers will bolt on fine, I bought crooked muffs once and it was nearly impossible to tell.
Running no. of weeks without breaking something in the lib: 0
No. of things still to fix in in the lib: 43
User avatar
alexeiwoody
 
Posts: 1894
Joined: Thu Jul 12, 2012 11:47 pm
Location: Melbourne
Car: MY07 LibGT 5EAT
Real name: Alexei

Re: What causes exhaust drone ?

Postby scottb721 » Thu Oct 24, 2013 10:04 pm

Just waiting on a shipping quote from TCP then will choose. Probably be about a $280 difference between them and the hi-techs.
08 3.0 spec B
User avatar
scottb721
 
Posts: 170
Joined: Wed Feb 06, 2008 8:39 pm
Location: Nelson Bay / Newcastle NSW
Car: 2008 3.0R spec B auto sedan
Real name: Scott

Next

Return to Exhausts

Who is online

Users browsing this forum: No registered users and 1 guest