Silencing the exhaust

[EG3]

I love the sound of my APS exhaust when the windows are down, at idle or when I'm accelerating BUT it gets annoying sometimes when I'm at low rpms at the highway.. I was thinking of doing one (or more) of the following so need some help (ideas) on it:

1) Replace UTR Z tube with stock: Might reduce noise but I feel like I am already getting a lower intake charge compared with all the exhaust mods
2) Replace Stillen box with stock: Same thing as above.
3) Add a muffler to the exhaust.

Now for the third option, I don't have much space on the setup. Below are two pictures of the setup.
Front:


Rear:


I'm thinking adding a tiny race muffler to the reverse y-pipe here:


The question is how effective can be a race muffler to reduce the noise and is there a muffler small enough to fit over there? The deep sound feels like it comes from some place between headers and the reverse y. I'm suspecting the 3" diameter region between two Y connections..

I have around 4" of space between the Kakumei y-pipe connection and the beginning of the reverse y-pipe. Any suggestions? T

 

[Dr.2K]

I think removing the headers would solve the noise problem instead of anything to the exhaust.

 

[jbaker1121]

and then give them to me!!!!!!!!!

 

[EG3]

I think removing the headers would solve the noise problem instead of anything to the exhaust.

Affordable solutions? I can replace the whole rear muffler or maybe even replace the whole thing for the price I'll pay to remove the headers.. Plus, the goal is not to get rid of the sound at WOT. Removing headers will improve the low range "rumble" only marginally.. At least that's what I experienced with stock exhaust. It deepened the sound when I first got the headers but the real sound appeared mostly when I went WOT, not at low range..

 

[theMerchant]

you can always replace the resonators with larger ones. (longer)

 

[Dr.2K]

Yes, but you can then sell the headers to recoup some of the cost .

But are you referring to the exhaust noise at cruising low rpm's between 2-3k on the streets?

Did you think about putting the oem y-pipe back in? If that doesn't work then I think what themerchant has suggested is worth a try.

 

[Mikefx3508]

Who would want to do that? The sound is one of the reasons I wanted the car.

 

[EG3]

Who would want to do that? The sound is one of the reasons I wanted the car.

Did you hear mine? I'm not running a stock setup. Take a look at the signature.

I don't mind the sound when I go WOT or even accelerate moderately. It's the BOOMing deep deep sound that annoys me when I'm cruising at low rpms. Anyhow, found a good solution I believe. Will try to use this racing muffler insert in the 3.0" "container" I have on the reverse y-pipe. That should take care of the booming sound I believe and still keep the racing one while still not preventing the flow that much..

 

[theMerchant]

Did you hear mine? I'm not running a stock setup. Take a look at the signature.

I don't mind the sound when I go WOT or even accelerate moderately. It's the BOOMing deep deep sound that annoys me when I'm cruising at low rpms. Anyhow, found a good solution I believe. Will try to use this racing muffler insert in the 3.0" "container" I have on the reverse y-pipe. That should take care of the booming sound I believe and still keep the racing one while still not preventing the flow that much..

very interesting. how long is that part? I was wondering how to tone down my exhaust and this would seem to work fro me . I would put this inside my g35 extension piece.

are you going to try it out? please post your results.

 

[EG3]

very interesting. how long is that part? I was wondering how to tone down my exhaust and this would seem to work fro me . I would put this inside my g35 extension piece.

are you going to try it out? please post your results.

I'll see if we can fit it in the small y-pipe I showed above. I initally go this and will be using whichever fits since I have only around 4" extension in there.

This is a 6" muffler that slides into a 3.0" pipe and it has the same insert in it and the insert covers about the whole length. Both are cheap. One is $28 (IMCA muffler), the other is $15 (insert). Both from speedwaymotors.com

The appointment is this Saturday. Will be installing 2 rear GTSpec braces, front tie brace, front KYB struts and this exhaust work. Big day!

 

[theMerchant]

I'll see if we can fit it in the small y-pipe I showed above. I initally go this and will be using whichever fits since I have only around 4" extension in there.

This is a 6" muffler that slides into a 3.0" pipe and it has the same insert in it and the insert covers about the whole length. Both are cheap. One is $28 (IMCA muffler), the other is $15 (insert). Both from speedwaymotors.com

The appointment is this Saturday. Will be installing 2 rear GTSpec braces, front tie brace, front KYB struts and this exhaust work. Big day!

cool.

this is the piece I would stick that silencer into

 

[EG3]

If I remember correctly, the g35 extension is 2.5" in D though. The silencer fits 3.0"+ only.

 

[theMerchant]

If I remember correctly, the g35 extension is 2.5" in D though. The silencer fits 3.0"+ only.

I think your right. not sure. can we get some NIsmo exhaust owners inputs?

 

[gto]

G-Extention is a 3"
We bypassed it on Gil's ride and just did a connector pipe from Y to resonator

 

[theMerchant]

thanks Dave

yA! ... 3" and proud

 

[EG3]

yA! ... 3" and proud

that tiny? mine's 4" at the second y-pipe connection :glasses:

joking aside, that's what gives me the booming sound as well as the 4" long 3" D tube before it that is connected to another 3-4" long 3" D Kakumei collector. Add in the headers to the equation and I have cruising Harley sound (exaggerating here) at low rpms. Can't believe I actually bought Berk HFCs to add to this system..

 

[gto]

& you dont bog big time on the low with a 4? That's a crap load more volume to push through.

 

[EG3]

& you dont bog big time on the low with a 4? That's a crap load more volume to push through.

It's only 4" at the beginning of the y-pipe, right at the square flange intersection, I wrote that as a joke
View attachment 158840

I feel as much bog as it was before the whole exhaust. It's either a very small/nonexistent loss in torque or the vibrations from the exhaust numbs my ass

 

[gto]

What's the DIA of your midpipe?

 

[turbocad6]

ha, & your going to add berk hi flow cats too, I think they'll increase the noise level a bit too, I'm afraid to do hi flow cats at this point, I'm thinking like you, of trying to come up with a way to quiet my exhaust a bit too first at least, I'm thinking about adding a set of supertrapp tips maybe even, which are cool cause you can tune them, not too sure on the look but might not be bad really...