Apexi downpipe and catback still too loud or too much resonance

[AL92]

I am running the passive silencer in my apexi gt catback and downpipe combo.I have apexi active silencer on order.Still I find too much resonance or something.And it seems really loud still on deceleration from high revs.

So thinking of putting something in the downpipe.Shame as its stainless but maybe just cut and clamp something in there.

Choices a vibrant resonator either 12 inch or 18 inch not sure if 18 will fit and other choice is FLO PRO race twister bullet muffler .I installed one in my v8 car and it did the trick in that one.
The vibrant resonator is stainless the flo pro isn't. Not a huge deal car is not winter driven anyway.

I would have thought the apexi with two resonators would not have any resonance really but it still seems to.

So has anyone else cut the apexi downpipe and put in a resonator or muffler and what success have you had?

 

[RamenPride]

I put one of these between the cat and the cat-back:

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It increased spool time slightly, but the trade-off with reduced noise was well worth it (to me at least). The exhaust overall is a tad quieter, but that loud booming while decelerating in gear is nowhere near what it was like before.

 

[pneumo]

Make sure there are no leaks at the joints. If the gaskets don't seal all the way around you'll get plenty of resonance. I learned this the hard way.

 

[AL92]

I don't think have any leaks. And what is that summit thing.the pic is good but whats it called.Does it just slip into the pipe?

 

[Rob10_99]

I saw those bullet twister mufflers a while back, but never knew of anyone that put one on a turbo.
thinking of putting one in place of the meow-meow?

 

[AL92]

Those inserts are from car chemistry and they are sold on summit site.Pretty neat! I think will try one..so you went with two disc think go with three disc one. And you took out cap and thing on your or left cap in there and ring?

That decel boom gets on my nerves big time. Not sure if have much actual resonance think more just too loud under the drivers area.

I like the idea that you don't have to cut anything for these. Worth a try for sure. These and the active silencer should make my exhaust much more mellow.That is fine with me as both these things don't seem to show any dyno losses.A bit slower spool is ok not a huge issue. My 2.4 spins my 3065 up pretty quick anyway and noticed as I leaned things down the spool really picked up also.
The twister bullet would take cutting and so would the vibrant resonators. Think try this first don't have to hack my nice apexi downpipe up.
Thanks will order one of these today!

 

[RamenPride]

You do have to do some cutting to get it into the pipe, and then weld it or rivet it in place. If you don't, it will rattle around. I have a hi-flow cat that I put "into" the downpipe by cutting out a section between the hangers and the flange and replacing it with the cat, and then securing it with some exhaust clamps. That's how I was able to get the insert into the downpipe. I used four stainless steel screws to secure it in place, because I don't have a welder and my riveter is a piece of crap. I used the two disk 3" insert without the cap.

 

[AL92]

Hmm thought is was just press in fit..so what kind of cutting.starting to sound like a pain in the butt now! And you have a cat also..
I was driving mine today and it wasn't that annoying for some reason. I have heard if you are too rich it make the exhaust quite a bit louder and I was rich my pipes are full of black!
I am now tuning and leaning it down That should maybe make the exhaust even better.

So the 3 inch insert is too big for the 3 inch apexi. I would assume just the discs are slightly too big? I do have grinders and dremels to do what has to be done.Can't be that hard after doing a 2.4 swap!

So can I get a big more detail..was thinking get the 3 disc one. Not a big deal to rivet or drill I guess either.

 

[nightspeed87]

dont they sell 3in sound resonators? ( The straight through design kind )
Because if so I was just going to put like 2 of those up in my exhaust system both after the cat.... ( And do you have a test tube/ straight pipe ) ran after the down pipe in place of the cat, because that makes it louder than a high flow cat would....

( I agree with you guys though about quieting the exhaust...I am very particular about exhaust sound, and I just want a mellow deep rumbling sound at idle and low rpm thats not very audible from distance, but at full wot it has a aggressive roar to it that is still bearable. I dont like a loud screaming car even at cruising.. )