Im running stock cats on a Apexi Ex-Ti and the drone is really kicking my ***. The mid pipe already has a long *** resonator on it and using a silencer is not a option due to hindered exhaust flow. Anyone have any tips on how to reduce the droning?

 

basically the silencer is your only bet, since you are already running your stock cats.

 

weird. drive at a higher RPM

 

Twincharge. The turbo will quiet your exhaust.

 

would welding an H-pipe to the nismo Y-pipe help? The vortech is making my exhaust even louder it seems

 

You could lay 2-4 layers of eDead V1 through your trunk, etc.


You could wrap the exhaust pipe in eDead as well.


Silencer would be your best bet, an H pipe on the y-pipe won't do much or anything

 

dynomat your hatch which will be costly and time consuming. Over and above though, single exhaust with S/C is going to be loud.

 

you can always add resonators

 

+1.. resonators, guaranteed to reduce rasp, decibels, drone.. ect

 

B-Quiet under mat in rear... it’s lighter than dynamat and comparable sound deadening… I have Stillen gen 1 on my G sedan w/ Crawford HFC – a relatively loud combo with notorious drone… a good friend turned me on to B-Quite and sold be his mat… it doesn’t completely rid the sound but muffles quite bit. It’s a good option.

They have the adhesive stuff and L-Com & V-Com mats…. The mat is convenient because you can remove it at the track for weight savings:

www.b-quiet.com

 

really dont want to add even more weight to my already fat Z. Im gonna try to have a shope weld on two small resonators on my y pipe.

 

Break down $$$$$ and go true dual catback system

 

Do what I do, wear custom ear plugs. I have them for work but wear them when in the Z. I'm very happy with them.
I believe my plugs cut 7db or 9db out. Not much, but enough to take the edge off.

 

Have you looked into Apexi's Active Tail Silencer?

 

It may just be the long *** resonator is what is causing your drone.
Resonators don't necessarily reduce drone. It all depends on the natural frequency of the resonator, its placement and its interaction with the rest of your exhaust system.

Drone happens when enough parts of the exhaust system are all aligned on the same frequency. When they all sing at the same frequency, it resonates (or drones) badly at that one frequency. When you get drilled at one frequency loud enough and long enough it will give you fatigue and a headache.

You could try fabricating a new mid-pipe with a much shorter or different resonator. This will change the system tuning frequency.

Its hard to say where the system tuning will go, but it shouldn't necessarily cost alot to make a resonator change on just a mid-pipe. You could put any number of different resonators in there to see where it goes.

When you find a resonator that resonates out of phase with the rest of the exhaust system, drone is reduced or eliminated.

 

I think my mat for the entire trunk floor of sedan (which is big) weighs about 12 lbs... and it's removable... the size for Z would be several lbs less... how much would 2 resonators weigh?

 

Fabricate reinforcement mounts out of 3/8 inch steel that fit tightly around the pipe and bolt them to the unibody. The resonant freqeuncy will be attenuated by at least 3dB, which will have the inverse effect of increasing the gain of an audio amplifier by 3dB. You will cut the "power" of the audible vibration you are hearing in half at best. Essentially, what you are doing is lowering the Noise Floor of the ambient harmonics.

Let me know if you need help.