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hey guys

did a search but cant find many actual answers with proven results. everyone says 'yes my exhaust is quiet' but havent actually had it tested.

just got off the phone to a tester who claimed that no 3" system will be under 90db. can anyone prove him wrong? ive got a 3" split dump to a wide body hiflo cat, 3" cat back system with a hotdog muffler and jazma oval muffler. he claims it will be over 100db.

what have you guys got.

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my system is pretty loud, was a peII but took the centre part out and got a custom 3" straight pipe made for it or the same diameter. So i got a 3" dump big body cat and straight pipe to the rear >_<

My old 80mm catback with proper mid muffler and enormous rear muffler came in at 92dB at 4k. This was with a 3inch dump/front pipe and regular old ceramic 3 inch cat and highflow turbo.

I reckon the stock turbo would have dropped it a touch more as there was a noticable increase in exhaust noise after i went highflow

yeah would be hard to find a 3 inch that'll make it under 90db

mine used to be 115, but that system was rediculous...

stop livin in the past man !!!!!

:)

how do you measure the db's anyway? i havent got a db meter.

CES dump pipes and 4 in straight thru no mufflers at all (track only car so no Cat) its fkn loud

Hang on is that a dB tester up my ass...when i extract it Ill get a reading

Edited by gtr660hp
3inch all way, as quiet as my wifes 'frontal' wet-farts

:):P:O

farken hell, did ya have to ??? huh? damn :O

i just put a 3" highflow cat on my turbo back 3" exhaust (mild steel, mandrel bend). and the fuccker is now slightly louder, but also very droney. i cant stand the drone. dont like the drone. would like the drone gone.

will a resonator return it back to the nice throaty note it had when running a 2.5" standard cat?

My friend has a db tested thing. Same as the exhaust place uses. He tested my exhaust at 108 db from memory. Then i made up this thing to go just after the cat. Just got a bit of tin cost me $1.75 from bunnings. Cut it to the size of the gaskit. drilled some holes in it and put in in the exhaust. Got may mate to test it again and it was 92db. The exhaust shop tested it at 86db.

Removed it after the test. I have a 3" system.

Mine was 86db at 800rpm... Went do 105db at 4000rpm or something stupid. Thats 3inch from the dump pipe back (stock dump). Just the cat and a cannon.

Then I got two big arse mufflers put on 84db at 4000rpm. Still 3 inch. Its just so much better, I can now hear my stereo on the highway.

the trust pe2 is def below the legal limit of 92db - it produces a very slight howl between the 3k and 5k range - but compared to the blitz nur spec its almost like a standard exhaust.... I think someone said its at 88db or there abouts

the trust pe2 is def below the legal limit of 92db - it produces a very slight howl between the 3k and 5k range - but compared to the blitz nur spec its almost like a standard exhaust.... I think someone said its at 88db or there abouts

The legal limit is 90dB for passenger cars according to the information available from the official ADR website:

http://www.dotars.gov.au/roads/motor/design/adr_online.aspx

in particular, ADR 28 is what I'm referring to.

Note that ADR 83 apparently supercedes 28; but ADR 83 has plainly been written by someone who was smoking

some kind of illicit substance at the time (it's full of conditions like "if it's the second tuesday in the month after 2pm

but NOT in a full moon, subtract 1dB UNLESS the car is owned by an Amish vegetable farmer in which case add

1dB ENSURING that the summer solstice is observed"). I had a quick browse through 83 and I was unable to

determine what the noise limit for my car within 30 secs; ADR28 allows ready lookup so plainly our pollies

are doing their jobs of making things even more incomprehensible.

Idiots.

edit: T04Z, HKS 50mm gate, 4" stainless exh, 6" cat, 6" resonator, large muffler w/ steel wool:

85dB with restrictor fitted and closed

89dB with restrictor fitted and opened

93dB with no restrictor

97dB with small 6" rear muffler

Any exhaust place with a dB meter can measure; the measurement procedure is defined in the ADR.

The meter is supposed to be calibrated regularly too.

Regards,

Saliya

Edited by saliya

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