Jump to content
SAU Community

Recommended Posts

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.

Link to comment
https://www.sau.com.au/forums/topic/142024-how-loud-is-your-exhaust/
Share on other sites

  • Replies 55
  • Created
  • Last Reply

Top Posters In This Topic

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

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • As discussed in the previous post, the bushes in the 110 needed replacing. I took this opportunity to replace the castor bushes, the front lower control arm, lower the car and get the alignment dialled in with new tyres. I took it down to Alignment Motorsports on the GC to get this work done and also get more out of the Shockworks as I felt like I wasn't getting the full use out of them.  To cut a very long story short, it ended up being the case the passenger side castor arm wouldn't accept the brand new bush as the sleeve had worn badly enough to the point you could push the new bush in by hand and completely through. Trying a pair of TRD bushes didn't fix the issue either (I had originally gone with Hardrace bushes). We needed to urgently source another castor arm, and thankfully this was sourced and the guys at the shop worked on my car until 7pm on a Saturday to get everything done. The car rides a lot nicer now with the suspension dialled in properly. Lowered the car a little as well to suit the lower profile front tyres, and just bring the car down generally. Eternally thankful for the guys down at the shop to get the car sorted, we both pulled big favours from our contacts to get it done on the Saturday.  Also plugged in the new Stedi foglights into the S15, and even from a quick test in the garage I'm keen to see how they look out on the road. I had some concerns about the length of the LED body and whether it'd fit in the foglight housing but it's fine.  I've got a small window coming up next month where I'll likely get a little paint work done on the 110 to remove the rear wing, add a boot wing and roof wing, get the side skirt fixed up and colour match the little panel on the tail lights so that I can install some badges that I've kept in storage. I'm also tempted to put in a new pair of headlights on the 110.  Until then, here's some more pictures from Easter this year. 
    • I would put a fuel pressure gauge between the filter and the fuel rail, see if it's maintaining good fuel pressure at idle going up to the point when it stalls. Do you see any strange behavior in commanded fuel leading up to the point when it stalls? You might have to start going through the service manual and doing a long list of sensor tests if it's not the fuel system for whatever reason.
    • Hi,  Just joined the forum so I could share my "fix" of this problem. Might be of use to someone. Had the same hunting at idle issue on my V36 with VQ35HR engine after swapping the engine because the original one got overheated.  While changing the engine I made the mistake of cleaning the throttle bodies and tried all the tricks i could find to do a throttle relearn with no luck. Gave in and took it to a shop and they couldn't sort it. Then took it to my local Nissan dealership and they couldn't get it to idle properly. They said I'd need to replace the throttle bodies and the ecu probably costing more than the car is worth. So I had the idea of replacing the carbon I cleaned out with a thin layer of super glue and it's back to normal idle now. Bit rough but saved the car from the wreckers 🤣
    • After my last update, I went ahead with cleaning and restoring the entire fuel system. This included removing the tank and cleaning it with the Beyond Balistics solution, power washing it multiple times, drying it thoroughly, rinsing with IPA, drying again with heat gun and compressed air. Also, cleaning out the lines, fuel rail, and replacing the fuel pump with an OEM-style one. During the cleaning process, I replaced several hoses - including the breather hose on the fuel tank, which turned out to be the cause of the earlier fuel leak. This is what the old fuel filter looked like: Fuel tank before cleaning: Dirty Fuel Tank.mp4   Fuel tank after cleaning (some staining remains): Clean Fuel Tank.mp4 Both the OEM 270cc and new DeatschWerks 550cc injectors were cleaned professionally by a shop. Before reassembling everything, I tested the fuel flow by running the pump output into a container at the fuel filter location - flow looked good. I then fitted the new fuel filter and reassembled the rest of the system. Fuel Flow Test.mp4 Test 1 - 550cc injectors Ran the new fuel pump with its supplied diagonal strainer (different from OEM’s flat strainer) and my 550cc injectors using the same resized-injector map I had successfully used before. At first, it idled roughly and stalled when I applied throttle. Checked the spark plugs and found that they were fouled with carbon (likely from the earlier overly rich running when the injectors were clogged). After cleaning the plugs, the car started fine. However, it would only idle for 30–60 seconds before stalling, and while driving it would feel like a “fuel cut” after a few seconds - though it wouldn’t fully stall. Test 2 – Strainer swap Suspecting the diagonal strainer might not be reaching the tank bottom, I swapped it for the original flat strainer and filled the tank with ~45L of fuel. The issue persisted exactly the same. Test 3 – OEM injectors To eliminate tuning variables, I reinstalled the OEM 270cc injectors and reverted to the original map. Cleaned the spark plugs again just in-case. The stalling and “fuel cut” still remained.   At this stage, I suspect an intermittent power or connection fault at the fuel pump hanger, caused during the cleaning process. This has led me to look into getting Frenchy’s fuel hanger and replacing the unit entirely. TL;DR: Cleaned and restored the fuel system (tank, lines, rail, pump). Tested 550cc injectors with the same resized-injector map as before, but the car stalls at idle and experiences what feels like “fuel cut” after a few seconds of driving. Swapped back to OEM injectors with original map to rule out tuning, but the issue persists. Now suspecting an intermittent power or connection fault at the fuel pump hanger, possibly cause by the cleaning process.  
×
×
  • Create New...