EPA exhaust noise notice - good muffler?

4GTuner

Help Support 4GTuner:

ocyrion

ocyrion

Well-Known Member
Joined
Mar 12, 2008
Messages
256
Location
Melbourne
Hey,

I've got a CC GSR w/ Evo 1 motor, which came with a 3" exhaust from the turbo. It has a large cat, hotdog and large muffler on the back (not a cannon). It's a bit noisy, particularly on overrun so I am looking for suggestions as to how I can quieten it down to the keep the greenies happy.

The exhaust place I went to suggested I fit a 2.5" semi-baffled muffler at the back to replace the current one, but it seems a little stupid to go from 3" to 2.5".

What are some QUIET but decent flowing 3" inlet 3" outlet or 3" inlet twin 2" outlet mufflers I can get that will keep me under that magical 90db while retaining power?

I want to do the job properly, not looking for a temporary fix to get me in trouble again later :p
 
I think you'll really be struggling to get under 90dB from a 3'' exhaust, especially keeping in mind that from factory the early evos were rated at ~86dB (thats with a 2'' exhaust, restrictive cat and pea shooter muffler).

The most 'proper' way to do this is to fit a varex muffler like some of the guys here have done. But keep in mind that any form of exhaust valve regulation is 'illegal' under EPA guidelines... that said no one will even notice unless they conduct a comprehensive inspection.
 
From memory Clause 18 from the Protection of the Environment Control (Noise Regulation) 2008 discusses 'noise control devices' and that you cannot fit anything that adjusts the noise level output coming from the exhaust system - there's 2 NEW points listed that came in 2008. This means silencers in the end of mufflers, steel wool packed into the cat or whatever wierd and wonderful coccoctions there are out there became illegal (unless otherwise fitted by the vehicle manufacturer so thats why the Holden W400 and Ferrari etc can pass this clause). The 2008 part of the Legislation didnt come fully into effect til September 2008. Whereas the previous 2000 Legislation didnt have anything about the noise control devices written in it. If you do fit a Varex, its still considered as one of these such devices so if you have to clear an exhaust noise level test they wont allow it. Its good to get one as a proactive measure to keep things quiet when you have to NOW before its too late (close it up when you see a police car or get pulled over etc). Other than that you could try buying a 15" long resonator or something to help quieten things down. You'll need a big one, not some small hot dog type either. Something to note is that the Police can only make the allegation that you have exceeded the noise db limit, and without a properly conducted noise level test SHOULD NOT issue you with an infringement. They may however get you for 'non standard exhaust' which is a load of shit in my opinion, but they cant word it as 'muffler too loud etc'. You can be directed to a facility to have the test conducted which will determine the allegation, in which the meantime gives you time to change the muffler etc :) Like mentioned, be proactive rather than reactive.

Oh forgot to mention. Guys with WRX's and turbo Nissans seem to be having some success with helping quieten down their cars with a MP01/MP02 X-Force muffler and a resonator.
 
The exhaust test bloke at the exhaust shop said he can't pass the car with one of those Varex remote mufflers, so that's a no go unfortunately.

How does the 3" into 2.5" semi baffled muffler sound? He said $180 for it, all flanged as per the original. A Redback F727GP muffler. Will that massively gimp the power? He said I might pick up some low end torque though. The previous owner spent $700 on this exhaust so it's a bit of a shame to have to defile it because some cop who got a crap donut that day felt like being unkind. I hope the ricer in the OBSCENELY loud Gemini in the lane next to me got done hard!

I scored 90 db at 4500 rpm but it still gets the jacks' attention.
 
Just added this above:
Oh forgot to mention. Guys with WRX's and turbo Nissans seem to be having some success with helping quieten down their cars with a MP01/MP02 X-Force muffler and a resonator.
 
Hot topic at the moment in this scene unfortunately....I have subscribed to this thread to see what you end up doing, as i have the same exhaust setup as you currently and am getting a little worried with all this talk lately, of EPA.
 
I have a 3" and got a 2.5 inch baffled muffler, it sounded awful, the pressure is bouncing back and fourth before it exits, it pops like a bloody rally car. I took it off after a few weeks.

I am very interested in this topic too and have been considering getting an entire new 2.5 inch system made as I am so over loud cars.

Realistically, if your car is making say <200kw, surely a 2.5 inch system from firewall back should not restrict too much?
 
I called Xforce in Melb, they said $280 fitted for the MP01 or MP02, that's to cut and weld the muffler on, or $350 if they flange it up to my existing setup to replace the last muffler. They wouldn't give me any guarantee it would pass though so I'm not so confident ... The videos on Youtube of the Hondas with these mufflers seem all right though.

I'm over the farting too, one of my old Cordias used to fart its arse off, I was embarrassed to go down hills on overrun :wub:

Definitely won't be getting a whole new exhaust, but I am a bit over the noise as well, esp on the freeways. But at least everyone knows I'm there, nobody ever tries to merge into me.

Does anyone know of a Lancer (or other car I guess) passing the 90 db requirement with one of those MP01/02s?
 
lol.. quiet car = slow car. i suppose it'd be alright if it were for low boost applications only, but i would suggest a standard muffler flanged behind the rear diff.. then maybe a varex AFTER it clears epa testing. my 3" tbe with a 1.5" muffler read 82db :p
 
One of the Varex twin tip oval mufflers is a good stealth muffler as its got 2 x 2.5" outlets out the back. no one expects a twin tip to be adjustable. If the tip has a BIG 3-4" outlet however, expect the Police to get a hard on for it :)
I dont think there is any exhaust shop that will guarantee to be under the db limit unless you sign them a blank cheque.
 
ocyrion said:
Hey,

I've got a CC GSR w/ Evo 1 motor, which came with a 3" exhaust from the turbo. It has a large cat, hotdog and large muffler on the back (not a cannon). It's a bit noisy, particularly on overrun so I am looking for suggestions as to how I can quieten it down to the keep the greenies happy.

The exhaust place I went to suggested I fit a 2.5" semi-baffled muffler at the back to replace the current one, but it seems a little stupid to go from 3" to 2.5".

What are some QUIET but decent flowing 3" inlet 3" outlet or 3" inlet twin 2" outlet mufflers I can get that will keep me under that magical 90db while retaining power?

I want to do the job properly, not looking for a temporary fix to get me in trouble again later :p
Click to expand...

4G63T engine conversion into CC coupe.
I had fitted large cat, resonator( hot dog ) and straight through muffler at rear with 2.5 inch piping and passed yesterday with 88db.
Hope that helps.
Cheers
Paul
 
EVO-00X said:
One of the Varex twin tip oval mufflers is a good stealth muffler as its got 2 x 2.5" outlets out the back. no one expects a twin tip to be adjustable. If the tip has a BIG 3-4" outlet however, expect the Police to get a hard on for it :)
I dont think there is any exhaust shop that will guarantee to be under the db limit unless you sign them a blank cheque.
Click to expand...

I can't get a Varex since the test bloke said it won't pass, so as good as it looks, it's pointless for me.

The whole point of all this bullshit is to pass the f@#*(@* EPA requirements. But I want something permanent that is legal as well, even if it has to come down to a 2.5". Some WRX owners seem to be scoring better low-mid range performance by doing that as well...

I like those MP01 mufflers but I'm not confident they will be under 90db.
 
EVODAD said:
4G63T engine conversion into CC coupe.
I had fitted large cat, resonator( hot dog ) and straight through muffler at rear with 2.5 inch piping and passed yesterday with 88db.
Hope that helps.
Cheers
Paul
Click to expand...

What make/model of muffler and resonator have you got on that EVODAD?
 
Also look at the material from which your exhaust is made from. Different gauges of mild and stainless steel will resonate at different frenquencies and cause their own unique exhaust noise.
 
I have a JUNBL muffler, and 3" straight through from ther dump - nice tone and legal still too (under S.A. laws)

Mind you, I'm still running the stock 4G93T on my CC GSR.

Unfortunately you don't have Exhaust Technology in Melbourne, otherwise I'd thoroughly recommend them.

Walker Turbo with a resonator also had some success on my VR4'd Cordia back in the day....
 
I was just checking the Xforce Evo 7-9 exhaust video on their site. They have a brief DB test at the end, on a hand held thing, it appears to average at 86 db on revs and briefly jumps up to 92 db on overrun. The setup is 3" turbo back, a small cat, moderate sized resonator and one of their 6 x 10" oval mufflers (I believe it's the MP02 model).

My exhaust has a large cat, quite a large resonator and is 3" ... I'm thinking of getting one of those MP01 or MP02 mufflers on the end of mine and reducing to a 2.5" inlet into the final muffler. I wonder if that will make enough difference to get it under the 90 db. Any thoughts?

EVODAD - don't worry about checking out your exhaust if it's a hassle for you.

boostboy - what's legal in Adelaide? Isn't it 90 db or under for the whole country?
 

Similar threads

EVO-00X
AMEP stance on Vehicle Exhaust Noise and Emissions Amendments
Replies
4
Views
2K
penngwyne
penngwyne
VIN18M
Exhaust - 2.5" or 3"
Replies
15
Views
940
BYBY5L
BYBY5L
W
rvr hsg rear muffler
Replies
4
Views
904
PROGSR
PROGSR
E
FS: 4G63 / Intercooler kit / exhaust muffler
Replies
2
Views
903
evopwr
E
oggy
CC GSR for sale VIC
Replies
8
Views
2K
oggy
oggy

Latest posts

Back
Top