Exhaust

[shaun123]

Hi, i just wanted your opinions on how big of a exhaust is too big? I just put on a 3.5" (or maybe even 4"), havent measured it yet since i got it for free, anyway I feel that its abit loud, is there a way i can silence it without putting on a stockie or anyone have exhaust sizes this big?

what are your thoughts on them

thanks

[Wink]

3.5"/4" is big but not excessively big

If you want to lessen the noise you could use an Apexi EVCS or get some hotdog/resonator pipes made up in between your cat and muffler tip.

[AlexCim]

i dont think anything over 3.5 inchs is really needed.

I think 5 inchs is too big.

[mazgtr]

Yeah you can start to run into ground clearance issues aswell once the exhaust pipe gets to big. 3.5inch is plenty for up to 400KW at the rear wheels.

[r32line]

Generally a loud exhaust will be due to the exhaust itslef rather than its size. I had a 3" cat back that would drone terribly to the point were i would get headaches driving the car, but it was because it was simply a crap exhast the previous owner fitted. Got a new turbo back 3" which is much quieter, but still powerful and has a nice sound...

A friend has an r32 too with a 3.5" pipe and his is just as quiet as mine.

but maybe u could hotdog it, depends on how loud it is atm, cause a bit of a reduction in the noise mite not be enough.

Edited June 21, 2006 by r32line

[shaun123]

i just measured it and its 4.5"(the muffler) , the exhaust is 3inch all the way can i get some kind of silencer for this? there are two little holes towards the end of the muffler and someone told me this is to put a silencer, is this true?

I've only had it for a day and im finding its quite annoying on long drives, and generally would this be over 90db or watever they allow for?

Edited June 21, 2006 by shaun123

[Wink]

i just measured it and its 4.5" can i get some kind of silencer for this? there are two little holes towards the end of the exhaust and someone told me this is to put a silencer, is this true?

I've only had it for a day and im finding its quite annoying on long drives, and generally would this be over 90db or watever they allow for?

Yes the little holes are so you can bolt on a silencer and yes a large exhaust like yours would probably be over the 90db limit.

[dano4127]

i have a turbo back 3.5" kakimoto on my car it is really quiet

no way near as loud as half of the lancers fitted with canons!

[r32line]

i just measured it and its 4.5"(the muffler) , the exhaust is 3inch all the way can i get some kind of silencer for this? there are two little holes towards the end of the muffler and someone told me this is to put a silencer, is this true?

I've only had it for a day and im finding its quite annoying on long drives, and generally would this be over 90db or watever they allow for?

Well i have the exact same setup, 3inch pipe with 4.5 inch tip and its not loud at all, you must just have a bad system. A silencer can be fitted but you will loose almost any power the exhaust was giving you

[shaun123]

Well i have the exact same setup, 3inch pipe with 4.5 inch tip and its not loud at all, you must just have a bad system. A silencer can be fitted but you will loose almost any power the exhaust was giving you

hmm same setup huh, is yours really quiet? do you have some kind of a sound file of your car running. Maybe cos my car is NA its loud?? or maybe im just exaggerating and its really not as loud

[djr81]

A N/A exhaust will, as a rule, be louder than a turbo exhaust.

As a guide my exhaust is 90mm & I literally cannot hear it over the tyre noise.

By the way, an exhuast is too big if you have to check for the cat sleeping in it before you start the car...

Edited June 22, 2006 by djr81

[Beer Baron]

A N/A exhaust will, as a rule, be quieter than a turbo exhaust.

As a guide my exhaust is 90mm & I literally cannot hear it over the tyre noise.

By the way, an exhuast is too big if you have to check for the cat sleeping in it before you start the car...

actually it's the other way around. in general (with aftermarket exhausts) NA cars are louder as there is no muffling bettwen the exhaust ports and the pipe/mufflers etc. but on a turbo car you have a turbine (or two) that muffles the sound.

[djr81]

Hey that is not fair, Richard. I fixed my post before you fixed it for me. Beat you by a minute...

[Beer Baron]

haha, sorry!

[Dee 33]

If you don't want to get a silencer, go to an exhaust shop and spend a little on a quiet muffler.

Exhaust size and even power has little to do with the noise. It's all in the muffler.

There's a reason my Suzuki Sierra is louder than my Skyline and exhaust size and power have nothing to do with it.

It's all in the muffler

[mazgtr]

My GTR came with a full 3.5inch system and 4.5inch straight thru cannon muffler that did nothing!!! You could hear the car comeing 3 miles away. It would of been close to 120Decibels!!! Before i got defected i decided i had to change mufflers, but i couldnt find a quiet internally 3.5inch muffler. So i had a custom 3inch straight thru sports muffler made up. Its about 3foot long and a foot and a half wide, its absolutley massive!!! I had it made with twin 2.5 inch tips so it looks stock from the oputside. It knocked 30decibels off the exhaust, and has made it far more liveable. On the down side it did cost me 4KW at the wheels, but its still worth it.

[R33TOM]

sorry to hijack the thread, but is there any real proof that you will lose power from putting a silencer on? as its acting as a restrictor at the end of the muffler

Edited June 22, 2006 by R33TOM

[benm]

I think you just answered your own question.

[thrtytwo]

i think 3" is fine for street app

3.5" maybe for a massivly modified car

4" straight through for a pro drag / circuit car

my opinion anyways

[R33TOM]

err what i wanted to know is, if anyone actually dyno tested to see if a silencer actually does reduce your power,

from what i read from the apexi silencer on their website, high end power does not get affected and you gain midrange torque