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Need A Quiet Exhaust - Copped A Epa!

FULOCK

By FULOCK,
in Engines & Forced Induction

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FULOCK Collaborator

FULOCK

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Posted

Hi all,

I just recently received a lovely EPA notice in the mail to get my exhaust tested for noise.

I personally didnt think my car was that loud - but it does fail.

The new EPA laws state that the noise needs to be under 90db, including when you back of (the drone/rev down also cannot go over 90db)

I have a R34 4-Door with a Blitz NUR Spec cat back exhaust - what exhausts/options do I have to get her quiet but still let her breath with a good exhaust???

I want to make it a permanent change - not a quick fix just so i can get the EPA off.......

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FULOCK Collaborator

FULOCK

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  • Author
Posted
maybe a resonator would help ..ask your local exhaust shop

yeah that was the first thing I asked....... they said forget about it, it wont help.

I was suprised at that... do resonators make that much of a big difference??

maybe i should get a second opinion ay??? :(

dangerous_daveo Grand Master

dangerous_daveo

Posted
Posted

Mine used to be 86db at idle and 106db at 4000rpm or so, and is now 84db at 4000rpm. I got two big arse mufflers put on, still all a 3 inch system tho, and I didnt have too much of a loss of power. So maybe you could get away with a resinator and a big arse muffler. If thats any help.

Cost me about $300 including the db tests.

rgr34 Proficient

rgr34

Posted
Posted

i also got epa recently...... i put the stock muffler back on.........but seeing u want a permanant fix you would probly need a large oval style rear muffler which u can get in 3 inch strate through.......all those canons are going to be loud.... and geting bigger centre resonator does help abit.......

damuscat Community Regular

damuscat

Posted
Posted

A resonator after you cat will help a lot. I've got a decent sized resonator (not the hot dog style) and an oval muffler on the end with 3" stainless piping all the way. Although it's never been checked I was told by the exhaust shop that the setup is under the 90dB limit (they said it should be about 88dB). Apparently a cannon muffler would put it just over.

I personally would like it to be a little louder than it is but the whole point of getting it done that way was to avoid attracting any attention to it. I still got a noticeable performance gain and I guess that's the main point of doing the exhaust in the first place :)

Birnie Veteran

Birnie

Posted
Posted

Just found this on the Jap Yahoo auctions.

Translated it seems to be a quitening Cat Converter that drops noise by 10db

Wouldn't mind one myself.

Commuting noise an hour each way is getting a little annoying

Slidewize should be able to get you one.

http://page15.auctions.yahoo.co.jp/jp/auction/t29306014

G_Force Community Regular

G_Force

Posted
Posted
Hi all,

I just recently received a lovely EPA notice in the mail to get my exhaust tested for noise.

I personally didnt think my car was that loud - but it does fail.

The new EPA laws state that the noise needs to be under 90db, including when you back of (the drone/rev down also cannot go over 90db)

I have a R34 4-Door with a Blitz NUR Spec cat back exhaust - what exhausts/options do I have to get her quiet but still let her breath with a good exhaust???

I want to make it a permanent change - not a quick fix just so i can get the EPA off.......

How did the EPA know ur over the limit? Did u get a licky and a noise test done at the pits? Which state is this happening in?

As for ur fix, i'd say replace the Blitz muffler with an oval type one, shame tho coz it'll just restrict flow once again.

FULOCK Collaborator

FULOCK

Posted
  • Author
Posted (edited)
How did the EPA know ur over the limit? Did u get a licky and a noise test done at the pits? Which state is this happening in?

As for ur fix, i'd say replace the Blitz muffler with an oval type one, shame tho coz it'll just restrict flow once again.

I got done in my own drive way dude!!!!!

driving home from the gym, i didnt even see them, i get outa my car at home and i see a cop in my driveway...

get this..... im dripping sweat, i have a towel and a bottle of water in my hand, and they still gave me a breath test. As if you'd knock down 6 beers after the gym????

they reckon it was a random check, didnt mention anything else...... a week later.... EPA notice in the mail......

ohh and im in vic by the way.....

Edited by FULOCK
evlgtr Proficient

evlgtr

Posted
Posted

Hey guys, i drive a R32 GTR and i got epa about a month ago..

As my exahust i have a 3 1/2 inch cat back system and the car was way too loud for standard 90 DB, so what i did, i wealded a plate in between the front pipe and the cat....

This has brough me down to 88 DB making me just pass....

But make sure guys when you do this that the plate is propperly wealded to the cat with three 10 mm holse in the plate that you are going to weald also try not to drive the car not over 3 thousand rev's others wise you will blow your exhaust seals...

Guys if you get this and you have to go there, dont go there with just a plate in between, otherwise you will get a $500 FINE!!! at Maclouds

hope to be a help

Woody1 Enthusiast

Woody1

Posted
Posted (edited)

you can have mine i hate it, i have no idea why anyone would have put it on the car, i can't even hear my engine with the windows up all i can here is the exhaust and the turbo :D its a 5 1/2 HKS superdrager stupid size bottoms out on bloody everything and yes it is all the way through why? i have no clue doesnt seem right to me at all :D dont think it would pass but :worship:

Edited by Woody1
Midnight R33 Contributor

Midnight R33

Posted
Posted

I got done not long ago too! I had a straight through 3" with an oval muffler at the rear. It wasn't really all that loud except for occasional crack and pop! It was 98db and got a mid

muffler box put in and is now 87db but feels like someone stuck a but plug up it!

I have been looking at some of the nifty gadgets A'PEXi have to offer like the 'Active tail silencer'

or that crazy valve you can put in your exhaust. But to get it cleared you will need something

noticeable that they can see, because they take photos from how it was before. Another person i know was actually aloud to put his cannon silencer in before testing..... didn't help him any though.

I have to say the EPA were very professional and helpful.

stolen_s15 Mentor

stolen_s15

Posted
Posted

Also check out the new varex muffler from x-force. It is a muffler that has a valve built in that opens and closes by remote control. When open its a straight through muffler, but when closed it diverts the flow through the sides of the muffler and is much quieter. It was reviewed in autosalon magazone this much, and apparently performed very well. I will be using or at least trialing it on my next car.

l_uk3y Proficient

l_uk3y

Posted
Posted (edited)

in regards to this. has anyone had much too do with those adjustable mufflers that can be set to be straight through, or quiet??? (as seen in several magazines now)

Does anyone have an idea of how loud a 3" turbo back, with sumthing like this (in db - set to its quietest setting) be on say an rb25??

p.s sorry if this is a hijack, although it could also be seen as a possible solution to the problem :P

edit: apoligies, didn't notice the post directly above me :P

Edited by l_uk3y

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