Blueevoix, do you hear any slight rattling at idle? I brought my car to the local shop and they can hear a slight rattle. They didn't like it cause of the misfire sound when the closes while revving at a standstill. I did notice I'm getting more false knock, maybe from the muffler. Anyone running tephra mod CEL knock light with this muffler?

 

At idle I do not hear any rattling. Also I dont have any noticeable issues revving at a standstill.

There is only 1 incident in which I here a little rattle and that is at start up. I'm currently running E-85 and the cold start up is a little rough. So during the first 1-3 seconds of start up as the rpms fall and try to rise from 500 rpm dip there is a slight rattle present. But that's only during the cold start up.

 

No rattles as of yet, but I will post as soon as I hear one.

 

Hey guys. I read through this entire thread and figured this muffler would be perfect as I'm looking for something that is quiet at idle and low loads, but isn't restrictive.

Ordered the '4.0L and larger version' and got it about a two weeks ago. I slipped it onto the current piping (while on jack stands since I haven't fabbed up anything that pulls the muffler up under the car enough to drive with it on) in place of a 3" straight through can type muffler and noticed three things:

1.) The valve doesn't move at all when free revving the motor. I'm sure this is just a lack of exhaust volume that will be solved when the car is under load. Anyone else notice this?

2.) No rattles at all. I'm happy about that.

3.) The car at idle doesn't seem any quieter than with the 'can' on it. The space around the valve also seems a lot larger than in the photos in the thread. Is everyone else getting 'stock like' sound at idle?

Note: I drive a 2002 WRX. I don't know how much of a difference that would make.

 

1.) It doesnt open when giving light throttle. Especially since at a stand still there is less load and less exhaust pushing it. But if you give it some more throttle at a stand still you will see it move open then shut again.

2.) Same here no rattles.

3.) There is slightly more space with the revised version. The picture I have up is the first muffler I got that rattled. The revision they made was adding more clearance. You could take a pic and post it here for us to take a look at if you like.

My self and many others a like with an Evo (OEM cams or very smooth cams) are also getting the "stock like" sound level during idle and normal driving. I'm not sure how much that boxer motor makes a difference. Did you clamp it on tight so it doesnt leak? Also did you drive around to see how it sounds during normal driving?

 

I have been watching this thread closely and it has persuaded me to buy one of these mufflers in the future for my EJ25. Your boxer rumble from your 02 WRX unequal length headers will pulsate unevenly against the valve, as compared to the EVO crowd. Your audible and rpm-opening results will vary. The 4G63 is a different and arguably better-breathing motor all around, and can probably flow more air at lower RPMs than your EJ20. So the comparison will not be apples to apples. Do you have a sound or video clip?

 

I took a picture of the valve this afternoon. Doesn't look too different from the picture on the first page.





Holding it in my hand though, the valve seems like it has a pretty big gap in it.

 

^^ Looks like its the same as mine. The revised version has a larger space so that the back end doesnt touch the inner wall. The first version had a tight clearance and the exhaust pulses that vibrated the plate caused the back end to touch the inner wall. This was the reason to the rattling sound.

Are you running a full turbo back exhaust or just a cat-back?

I've been running this on my car since summer and it sounds exactly the same as day 1, a very close to an exact OEM quietness.

 

hey blue you have any pictures of how this looks ?

 

I have a full turbo back, with one high flow cat, and one resonator. I haven't driven with it on because I only put about 4-5" of piping on a flange so I could slip it on, but the car needs to be jacked up in the rear because it isn't tucked up under the car. I may have to fab up enough piping to actually be able to drive the car around. I just don't want to have to weld anything to the actual muffler (like hangers) and not be able to return it if I don't like it.

 

I have not welded my setup. I simply slid the catback pipe into the Dynomax VT muffler and used a lap-joint band clamp to clamp it on. Then I took another straight tubing to clamp on to the muffler end to act as a tip as well. As for the hanger, I just used a cheap DIY strap hanger that I wrap around the pipe and bolt on to the rubber hanger on the chassis.

I'll take some pics after the weather clear ups from all the snow and dirt.

 

For those of you with this new muffler, did you loose any transient response?

I am looking to go this route after my neighbor expressed his dis-like for me going into work @ 4:30 in the morning!!

 

I didn't notice any response/power difference. However, I have S2's and the valve sounds awful. To the point where it is embarassing to idle infront of anyone without explaining it. It's been a few months now and I won't take it off. It is absolutely SILENT on the road. When I first drove it I thought the car stalled, it was so freaking quiet. If you don't have cams, it sounds like the valve clapping wont be an issue.

 

So your driving with aftermarket cams that causes the rattle/tapping sound and although it's embarrassing your still sticking to it ? Lol you must really enjoy quiet rides as much as I do ;-D

What is your idle set at ? Have you tried to smooth out the cam lopiness and or raising the idle more ? Maybe that might help getting rid of the noise ...

 

Oh boy :/ I have the same cams. The flapping noise is a no go for me. Are you planning on finding a solution for this?