looking for ideas on a bolt-on exhaust sound dampener???

[turbophein]

i have been kicking around the idea of making some sort of muffler that i can bolt on to my existing 5" muffler tip temporarily as an extra muffler. the car is annoyingly loud when just idling and working on it in the garage/driveway, and we just moved into a new house/neighborhood. i am not looking to get the neighbors hating me already. i haven't even started it yet since we moved in, it has been sitting for 3 weeks.

i just want some ideas of what you would do to clamp on to the exhaust and mellow the sound down. a friend said coffee cans and steel wool.. lol not my first idea but hey its a start.

someone should produce something like this for the late night engine tests, so you don't wake up the entire neighborhood.

 

[DynastyLCD]

what i've been considering, is welding in a couple of resonators to drop the noise level down. i think the one lap VR4 guys did this with some success, i don't remember the details though.

 

[TylerAdamson]

Pretty simple really. As said ^ weld in another resonator/muffler. Maybe add in a cat if you don't have one.

 

[turbowop]

I think he just wants something to attach to the back of the existing setup so that it quiets it while idling in his driveway when working on the thing.

 

[turbophein]

exactly wop...

bolt on when needed and take it off when your done.

 

[turbofonz]

Varex muffler... not cheap, but proper. Car doesn't have that dump exhaust cutout noise. Goes in like a resonator.

My buddies' evo:
varex muffler

I will say when closed the car is drone free and sounds stock. When open it sounds like an evo with a full 3" turboback.

 

[turbophein]

will choking the exhaust down to say 1.5" exhaust piping hurt anything?

i have a small oem 4cyl muffler kicking around, maybe i will try and fabricate and adapter to connect onto my 5" tip muffler on my exhaust. that should do the trick.

 

[JNR]

Probably could rig up a glasspack or resonator of some sort, or a large muffler, to slip on the tailpipe, but imagine it'd be long and sort of heavy (say a large muffler), although normally there is a hanger on these toward the tip IIRC that would help.

 

[James]

Quoting turbophein:
will choking the exhaust down to say 1.5" exhaust piping hurt anything?




For reals? /ubbthreads/images/graemlins/dunno.gif

 

[turbophein]

no for fakes... yes for real. its just for sitting idling in the driveway, is it wrong for me to want a somewhat stock sounding car when twisting wrenches in the driveway?? wtf

i have a plan, i will post back with some results.

 

[MellowVR4]

I've had experience with the amount of power lose by doin this. I did this to my old gti I had, and the power and acceleration was very very sluggish. I would just weld on some resonators.

 

[Barnes]

If it's seriously for just sitting still in the driveway, just buy a quiet, restrictive muffler that is smaller than the one installed on your car. Set it on the ground behind your car and run some all aluminum ducting from your exhaust tip to the muffler on the ground. You could just use hose clamps to hold it on.

 

[turbowop]

I think Barnes and I are the only two that actually have reading comprehension in this thread. /ubbthreads/images/graemlins/rofl.gif

 

[JNR]

Must've missed my post then /ubbthreads/images/graemlins/tongue.gif

Am curious though what sort of things will you be doing that require it to idle for extended periods of time?

 

[James]

What JNR said....

Unless you're just sitting in the car tuning. But he said turning wrenches so it lost me. I usually have my car off and battery disconnected lol.

To post something useful though.

I have a 3inch mag flow oval muffler and it's quite quiet. Even too quiet at time.

 

[JNR]

Yeah, same here, as far as working on car...usually always off unless I'm tuning or troubleshooting (testing), etc.

for ultimate portability, something like Barnes suggested would be good with the flex tubing...they make stuff specific for exhausts like you see for garages, also fwiw.

If you want to get nerdy an scientific, experiment with a noise cancellation device that cancels out the frequencies, electronically; or check out acoustic engineering stuff and make your own box, etc.

edit - just keep in mind that condensate will build up, so just need to design around it, or have a drain, etc...it won't flood it out right away or anything, but will build up if you were to do something that had a high point on the inlet and outlets and a lowpoint (condensate) with nowhere to go.

and, this probably doesn't need to be said but keep in mind the temperatures. Although being after the tailpipe it's probably not *that* hot.

 

[JNR]

some fyi stuff on what I mean (there is a lot more out there, this is just a quick google link):

click

Also, look at industrial setups on how they use air silencers and stuff on their exhaust and come up with a smaller scale DIY version...There is a ton of info out there on the subject, if you're interested.

 

[turbophein]

i must be special... do none of you tinker with your car at night? i am constantly changing or testing something new. right now i am working on a vacuum leak, i need to repeatedly start the car, also need to dial in DSmlink which also needs idle time. new turbo needs to go in, all that need idle time when done. running the vr4 at midnight as is, is not a plan of mine, but would be nice to be able to without waking up the entire neighborhood.

 

[Muskrat]

Quoting turbophein:
will choking the exhaust down to say 1.5" exhaust piping hurt anything?




Nope. Wont hurt a thing. You'll choke airflow from a WOT perspective, but you just want to quiet it when idling in your driveway, so no problems. You know those aftermarket mufflers that come with "silencers"? That's basically what they do. Make an insert that can be put into your muffler opening and attached with a screw or 2. It wont be "stock" but it will cut the noise a bit.

 

[turbowop]

Quoting JNR:
Must've missed my post then /ubbthreads/images/graemlins/tongue.gif

Am curious though what sort of things will you be doing that require it to idle for extended periods of time?



Sorry. I glanced over it when I saw the word "hanger" and assumed you were talking about adding onto the exhaust as well.

I've had my car sitting idling in the driveway before while setting fuel trims, burping coolant, setting idle speed, timing, etc.

In the last place I lived I had a neighbor that absolutely hated me because of this. Could be a summer night with the sun still out at 8:30pm and she'd come out screaming that my car is illegal, shaking pictures on her wall, and that she was going to call the cops. /ubbthreads/images/graemlins/rofl.gif I told her to go ahead. Nothing ever happened. But I totally get wanting to keep it quiet so as not to piss off the neighbors.