How Loud Is Your Exhaust?

[thorpe84]

my auto non turbo with f**ked cat and 5 inch autobarn fart cannon was soooooooo f**ken loud!

i loved that sonic boom resonation while going up hills at 50kph =)

[Paradizzle]

my auto non turbo with f**ked cat and 5 inch autobarn fart cannon was soooooooo f**ken loud!

i loved that sonic boom resonation while going up hills at 50kph =)

lol!!

[poppin13b]

My old s2 Rx-7 i got defected and sent to the epa

I had 12a extend port 2.5in piping through to 1 muffler

got 122.4db @ 4000rpm (but it did back fire when the guy backed off, prior to the back fire it was around 115-117)

after that i put an extra muffler in and one of those in car adjustable flanges in the middle and it brought it down to 95.2 db so i passed

No probs with my new car

its all stock

[Daz]

I would say mines around 130db @6k

[Trooper]

I would say mines around 130db @6k

Is it measured at a certain RPM?

has anyone got away with setting the rev. limit lower to pass? I have not had mine measured, but it has a nice note, prob very close to what is allowed.

I think it is a bit of a sign when you go to visit mates or family and 3mins before you arrive they are out the front waiting because they could hear you coming about 2kms away.

I had an old bloke a while back comment on how nice my car was and how good it sounded (must have sounded nice and quiet through the hearing aids). He commented on how good it was to see money being spent on a passion (i guess he meant cars are better than drugs) and how nice it was that I looked after it and kept it clean.

[saliya]

Is it measured at a certain RPM?

has anyone got away with setting the rev. limit lower to pass? I have not had mine measured, but it has a nice note, prob very close to what is allowed.

Depends where you are. In NSW, there are a few tests:

* Stationary noise test is at least 75% of the engine speed which corresponds to

maximum rated power. Say max power is 6000RPM, test is 4500RPM or higher.

Not less than 3000 RPM. Not louder than 90dB.

* Drive-by test is slightly different, and described in ADR28 (get this from the DOTARS website).

Approach at less than 50km/h in 3rd gear, WOT for 20m, close throttle. Can't be

louder than 90dB at any time.

*IM240 test - done at Penrith or Botany, PPM of particulates and gases measured.

Also has a noise component, also cannot be > 90dB at any time.

Don't think you can artificially lower your rev limit; and even if you did the flames would probably

be noisier

Regards,

Saliya

Edited November 10, 2006 by saliya

[SKY 34]

any increase in exhast dia. will give you a performance gain... it is better if its cat back obviously.

Cat back is all you really need anyway, turbo back is an unecessary expense... "bang-for-buck" wise anyways

I'm not sure about this one, either way if only part of the exhaust is changed, the airflow restriction is there...there is no point changing catback only, the dump front pipe already restrict the flow...

the same with changing front pipe and when the exahust reaches the catback, flow is restricted...

actually where does the droning come from? sound resonation due to pipe length? or because of the the type of resonator used...

actually I'm thinking if we can obtain the db of the exhaust, in theory we could get the wavelength and custom a pipe length such that the exhaust ends at a softer zone...if my physic serves me right...

[blackprincegts]

Well on my R32 GTS with a 2.25 catback with just a 4inch JUNbl cannon i would consider it VERY loud, the 1st time i got pulled over and had it tested it tested 91db. They made me get in the car while one officer watched that I held the revs at 3100rpm and the other officer stuck the reader at the end of the cannon. I measured 91 db and the cop said we wont worry about that because its only 1db over. 2nd time i got pulled over by a motor bike cop and he was so dam rude saying hes defecting me for my "extrememly defective exhaust note". same deal... tested 91 again and he let me go.... Anyway i dont getit why i havnt failed, i mean you can hear my car coming from streets away, i often think its a bit excessive for me. My work phone has a db reader onit, i did the same test and it read between 118 and 121 db's...

wierd..

[Silent]

Phones are not accurate enough to measure the db ratings. In wa police do not carry db testers. I was pulled up because of my exhaust and i told them it is adr approved and they said "oh" and let me go .

Do your police carry db testers?

I run a straight 3 inch turbo back with a high flow cat and a 4 inch muffler and one resinator.

Edited November 11, 2006 by Silent

[blackprincegts]

yep,dunno about ALL cops having db testers but the bike cop did and the other coppers that tested me were undercover traffic patrol so ja...

here in SA we also apparently had a trial of a system that takes a photo of vehicles that exceeded the legal db rating... that was like well over a year ago and i havnt heard anything about it since... they sed its set to a level that would mean you would have to well exceed the maximum db aloud on the street..

[Squishy]

I have a 4" HKS cat back system with a 5" cannon & a fake cat and it did 99db @ 3700rpm...

It made a real bellow... near impossible to be discreet around the po po!

It's getting changed before she's back on the road..

[SKY 34]

Phones are not accurate enough to measure the db ratings. In wa police do not carry db testers. I was pulled up because of my exhaust and i told them it is adr approved and they said "oh" and let me go .

Do your police carry db testers?

I run a straight 3 inch turbo back with a high flow cat and a 4 inch muffler and one resinator.

yeah in W.A the cops are not equiped with mics...no EPA as well

[SECURITY]

129db @ 4800rpm

[Coupe-This]

resonation sux anus ...

pipes straight off the motor for award winning purposes

now, a proper post ...

*loading ... *

the exhaust on my r33 was pretty loud and droney.

all i had on it was a 3" catback, with virtually no resonator, which then went into 4" with almost no muffler (tiny straight thru design) with a 5" tip

sounds nice, and angry

now my munro just is ridiucously loud, and has no drone, booyah

[123456]

Ah i just got EPA'd for having too loud an exhaust. Gotta take it in before next month.

The day in question, i was driving back from a performance shop with only 3 bolts in my dump, because of some snappage, so it was pretty loud.

Was thinking once i get it fixed itll be all good, but now.. Alot of people seem to get high readings. I've got split dump, 3" - 3" cat then 3" back to HKS super dragger muffler with 5 or 6 inch tip and from what i've read it seems like i'll be looking at 95db + (90 is all thats allowed in vic). Its a rb20 so i didn't think it was that loud. On idle it has a nice lumpy wrx-like note and inside the car the revving isn't very loud, with my mate driving it past me it sounds good but like, i've never set car alarms off. Are the rb25's much louder?. My pod used to drown the engine revs out. This topic has got me worried though.

How can i make it quieter temporarily? I need the flow.. Can i jam something up there, like idk feathers or something to make it quieter? Sucks because i've never had any trouble about exhaust noise b4

Edited November 23, 2006 by 123456

[700HP-GTR33]

I would say mines around 130db @6k

Rotaries are fun aren't they?

I think by memory....no rotary will pass epa in Vic without serious de-tuning.

Anyway..........

110db at 6700rpm.

At least that's what the EPA wrote down on inspection