teacher

iTrader: (1)

What do you think about this one...

I`ve had a JIC single on for about 8 months. I really enjoy the exhaust except for a boom/drone at 2200 +/- a couple hundred rpm, especially in 6th gear. This transates to roughly 60-70 mph. At least I have an excuse when they pull me over for 75 in a 55.... Y-pipe only changed the tone a tiny amount after the JIC istall btw.

I`ve tried:

1. Dynamatting as much of the rear floor as possible. There are some styrofoam corners that I didn`t bother pulling up. 8 square feet.

2. I stuffed some rags into the holes cut into the styrofoam (on the rear left corner above the exhaust) so that it would take away the volume of space in there. No need for a natural resonance chamber.

3. My spare is gone for weight savings, so I took a thin, 3/4`` foam mat and wrapped it ``snake like`` in the area to again take away from the ``subwoofer factor``.

I`d say I`ve reduced the boom by10-20% so far. Added 10lbs back to the car The car is definitely not unliveable, just boomy at some lower hwy speeds. Any ideas, such as going under the car with...?

Thanks.

Ruthless18x

iTrader: (59)

There have been a few posts on the sound of the JIC single. It's just a louder exhaust, which singles usually are anyway. Is it the Ti single? Is it resonated? Even if it's not you could get some decent money for it and buy a more quiet exhaust?

twenzel

iTrader: (27)

well, it will be a trade off, but if you put your spare and rear floormat back in, it will greatly reduce the noise, but also add more weight of course.

Ruthless18x

iTrader: (59)

I never thought of that, thats a really good idea.

Motormouth

iTrader: (44)

do you have the silencer in? don't the silencers increase the drone? trade off is it'll be much louder possibly.

ill350

iTrader: (1)

I have the Agency Power Ti single, and it is also very loud. I had AAM cut out a portion of the pipe and weld in a resonator. Makes a huge difference...........sounds GREAT

teacher

iTrader: (1)

Good comments guys, thanks!

It is the Ti version - saves about 40lbs (17lbs vs about 60) over the stock system. It is also resonated with a ~18`` larger diameter tube a foot or so back from the start of the b-pipe/middle of the car end.

I tried to use the foam mat, with some success, to `soak up` the noise that the spare had been blocking. It`s perhaps not as effective as a spare in that regard. It definitely is not filling up a ton of the space, but it helps.

********I`ve considered going to a shop for some added resonator work, but as I understand it, the Ti is not easy to work with. So, that leaves me with the y-pipe (a simple and inexpensive stainless steel one) as the portion of the exhaust that could theoretically be chopped/resonated.

What do you think? Have you ever heard of someone ``resonating`` the longer collector part of the y-pipe? Must be about...8``, 10`` or 12``? of pipe there to cut into after the 2 parts of the y merge?************

I could sell it, but it seems to make some nice power, and has a great sound when not stuck at the 2000-2500 cruise in 6th. I plan to dyno to measure the gains objectively. I was at 243 rwhp a year ago with a few mods but no exhaust or y-pipe which have been added to get ``the new power``.

Thanks for all the good ideas.
J.K.

1nate7

iTrader: (19)

This is probably your best option: https://my350z.com/forum/showthread.php?t=290311

The Y-pipe was sold, but there is some good info in there if you want to try to duplicate it.

teacher

iTrader: (1)

Jmckuhen has a great idea for mellowing the loud JIC single down. He added a Vibrant resonator ( 4 1/2 `` x 6`` x 10`` with 3`` in/out) to the end of his y-pipe (welds and flanges).

I`m wondering what the difference would be if one added a Magnaflow muffler of similar dimensions to the y-pipe instead of the resonator? The Magnaflow I`m looking at is #11219 which is 4``x 9`` x 20`` (body of the muffler is about 14``). Center in/out at 3``.

I ask because the Magnaflow appears to be cheaper, and if anything I`d assume it`d be as effective in mellowing the single`s drone.

*Does anyone have any info. on the construction differences/flow of a resonator to a muffler (similar dimensions)? Is the Magnaflow a quality piece?

Thanks!

eltness350

iTrader: (58)

wow if u only heard my DUAL 3inch exhaust.....lol...

z32-z33

iTrader: (3)

I also have a JIC but Its a ST, only the muffler is titanium, but yeah i do agree that the drone is kinda ridiculous. I just added a y-pipe and it seems to make the drone a little quieter but the drone is still there. I'm definitely curious about the whole resonated y-pipe thing, if you make one keep us posted.

kaos1

iTrader: (1)

JIC, or Agency Power.... i want to replace my nismo for a meaner/louder sound.

i was considering the topspeed or rsr exhaust, but im starting to like the single exit

BigZ88

iTrader: (2)

If you look at systems like the Greddy single, they actually have a secondary silencer in the mid pipe. With a ti system that will be more difficult, but if you find a shop with titanium welding capabilities, you could cut the ti mid pipe shorter, re-weld the flange back on, and make a new section with consisting of a muffler with 2 flanges welded on between the mid pipe and the ypipe.

just another thought.


edit...thats exactly what the guy did in the link posted above...sorry ignore me

Zexy

iTrader: (55)

Har har har.. Try JIC Ti Single non resonated w/ y pipe, and test pipes. The car vibrates violently at 4k-5k, interior resonance is CRAZY, and my friends tell me they can hear me coming, and i hear interior rattles.

I love it though Extremely wicked sound and i get compliments always.

kramykram

iTrader: (135)

Why not weld 2 smaller resonators after the flex joints. i think there is a good bit of space from the flex joint back if im not mistaken on the jic ypipe. I could be wrong.