How Loud Is Your Exhaust?

[ToF]

4" Straight pipe from turbo. Not sure. Definently yellow sticker here in WA

You wouldn't make it out of your street in Vic.

[nzm033]

hey would anyone know if removing the center muffler from a cat back would make the sound softer or louder?

i got a 3"splitdump, 3" cat, 3.5" HKS super dragger catback

the center muffler is way too low and scraps everywhere

if i remove the center muffler and replace it with a 3.5" piece will it alter sound??

reason i ask is ...the local exhaust shop said it would sound shit....but i need sound road clearance

[SKY 34]

I just ordered Blitz Nur...don't they come with the resonator to reduce the sound?

[saliya]

hey would anyone know if removing the center muffler from a cat back would make the sound softer or louder?

i got a 3"splitdump, 3" cat, 3.5" HKS super dragger catback

the center muffler is way too low and scraps everywhere

if i remove the center muffler and replace it with a 3.5" piece will it alter sound??

reason i ask is ...the local exhaust shop said it would sound shit....but i need sound road clearance

Replacing a muffler with a similarly-sectioned piece of plain pipe will make it louder (unless the muffler's not

really a muffler, which I've seen before, on some of the available-on-ebay systems )

Usually removing a resonator results in a 'brassier' note; harsher, a little louder.

If you're having clearance problems with 3.5" your exhaust has dropped a mount, or the car is too low

HKS stuff usually fits pretty well so I'd be checking the rubbers before I deleted a muffler.

I have an R32 with SK's suspension guideline setup (355mm centre-to-guard) and it's passed engineering

(that is, 100mm clearance _everywhere_) with a 4" system. If all mounts are OK, and it's still too low, you

_could_ try an offset muffler to keep it quiet and get more clearance (or, you could set the car to the correct

ride height ).

Regards,

Saliya

Edited November 7, 2006 by saliya

[MBS206]

No idea on my actual limit.

Have a 3" system, at idle, fair bit quieter then my mates. And I'm running a cannon. Although, sounds like a jet turbine when it hits 4500RPM at full boost...

[Munkyb0y]

Usually removing a resonator results in a 'brassier' note; harsher, a little louder.

brassy as in droney?

coz i want to get rid of the drone from my system, and am hoping a straight type resonator will do it.

besides the cat and rear cannon, there's no other mufflers/resonators on my system.

whatcha think ? will it do the trick?

[saliya]

brassy as in droney?

coz i want to get rid of the drone from my system, and am hoping a straight type resonator will do it.

besides the cat and rear cannon, there's no other mufflers/resonators on my system.

whatcha think ? will it do the trick?

hmm; brassier as in sharper/harsher. Think the difference between the sound of someone playing a trumpet

at normal level, and someone blowing the crap out of it but in the next room - the volume is the same, but

the tone is different.

Adding a resonator _can_ be used to cure 'drone' (if you mean a resonance at a particular RPM); but it needs

to be the right size and material - you need someone experienced to sell you the right resonator. If you only

have a rear muffler, chances are the right resonator will do just what you want - but you need the right one.

Regards,

Saliya

[Munkyb0y]

now only if this magical creature existed. lol.

i've asked around and got the same response... "it might fix it, it might not, but it will have some effect"

[saliya]

now only if this magical creature existed. lol.

i've asked around and got the same response... "it might fix it, it might not, but it will have some effect"

Should be pretty easy to solve this one.

Go to an exhaust shop, tell them what you want. If it happens at a particular RPM, show them the

RPM. Tell them _exactly_ what you want fixed, and ask whether they will back their work.

That is, if they do work but don't fix your problem, they won't charge you.

If you're reasonable in your expectation and you clearly communicate what you want to them,

an experienced shop will be able to say 'yep, this will do what you want'; or 'no, you can't do

what you want with the system you have' to within reasonable limits.

If they say 'we don't know what will happen' you don't want that shop.

The easiest way, of course, is to hear a car that sounds like what you want - and see if you can

replicate that

Regards,

Saliya

[Munkyb0y]

i will try some more exhaust places.

since 3 inch jap systems often have a cat > straight thru resonator > cannon, i figured that the resonator is what i'm missing. but since you brought up the point of different resonators for different results, i'm less confident now.

my exhaust sounded perfect when it had the restriction of the 2.5" standard cat. i just wanna offset the new highflow cat with a resonator. i'm just babbling on now. need an expert. unless you can give me a model and guarantee over the net. lol.

[jasont82]

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.

great idea i might just do that. wait and see how much im over first.

[Munkyb0y]

so have i got this right?

the less back pressure the better (rb25det).

so even if there was no exhaust at all, just a dump pipe, theoretically this would be good for performance?

[ctjet]

fark you ask a lot of question kent....

[Munkyb0y]

whatever bish !!!

kiss my ass

naaaaa s'ok

[ctjet]

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

[Munkyb0y]

why better from cat back? turbo back has got to be better, get the pressure away from the exhaust turbine quicker.

edit: i see you mean as far as performance for value. k then. i have turbo back. put a highflow cat, now exhaust note sounds like crud, and not so sure the car wasnt going better before.

Edited November 8, 2006 by Munkyb0y

[ctjet]

i think the answer you looking for is....

just smash out the fcuking cat... sounds unbelieveable

[SMR33]

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.

Had to have mine tested before going onto the skidpan at Mt Cotton in Qld, due to the circuit being near a residential area. 2 measurements were taken, one was at 3200rpm and the other at 4000rpm. My S2 registered 81db at 3200 and 84db at 4000.

At the time I had the standard dump and a 3inch cat back system. I have 2 mufflers (one is a jasma, the other i'm not sure). I now have added a custom split dump and a new cat. Have not had it measured since the changes.

[saliya]

so have i got this right?

the less back pressure the better (rb25det).

so even if there was no exhaust at all, just a dump pipe, theoretically this would be good for performance?

A turbo will work the best with nothing behind it, yes.

Of course, you'd set fire to everything that was directly behind it, but meh

Regards,

Saliya

[Munkyb0y]

ok, coz i'm not convinced that the car wasnt performing better before the highflow cat came into the equation.

but i guess that's unfounded, seeing as it's created more noise, hence more flow, and unfortunately drone.