Quieter Exhaust addon's....

this is probably in the wrong place but just wondering what is out there that can quiet my exhaust system?

currently I have CI header, and 2 pipes going to separate 14inch magna flow mufflers, I don't want this stealth but I want it quieter for the road, the current noise going down the road is fun, but i'm afraid on road trips it's going to be too much of a headache...

Can I get some insight?

(I tried to get 18inch magna flows but the muffler shop didn't want to install them, so i got the 14inchers)

Edit: what about Resonators? or Silencers? would that cut down on the sound but not eliminate it?

I believe they sell exhaust tips that will mellow it out a bit. Kind of like the tips on old VW's.

I went to generic turbo mufflers. Was much better for cruising, but still had a nice rumble to the note. I had flowmaster 50s before that.

I recently deleted the catalytic converter on my '78, and was astounded at how much louder the engine was.
So I say put a cat on it, that'll shut 'er up.

8) you can get exhaust tips that have resonators built in to help reduce the noise. i like the dual tip style.

a trick with Flomasters is to take glasspacks (i like Purple Hornies, simply because of the name) and put them upstream of the muffler
it acts like a resonator, and helps reduce the drone you get with Flomasters

worth a shot, PHs are pretty cheap, i think a friend got a pair for $20 each several years back

Asa, That's Exactly what I was hoping to do, is to put something upstream. Because I like the sound but not the volume, would glasspacks change the tone? how much of the drone?

so being uninformed, are resonators before or after the muffler? and silencers (i'm guessing after...)
Cobra, do you have a sound clip of your turbo's?
In the end i'm hoping to go from current 100% volume to 35-50%.

Isn't there a website that has all sounds possible for exhaust systems?

Edit: I'll post a sound clip of my MagnaFlows, and I like my exhasut tips.

I would personally go with something along the lines like a resonator, doesn't really decrease the flow much but knocks back the sound on highway alot. you can usually find them at most places that sell custom made exausts. You would be suprised at the sound difference, I had a buddy that removed the resonators from his bmw and that sucker was loud, so he put one back on and got the throatier sound that he was looking for without the rasp. I know of a website that you can get them at but i have to find it or remember the exact name first. I'll post it up for you as soon as i find it.

well darn i could have sworn i had it somewhere saved in my favorites but now i can't seem to find it . Either way you can find them on summit or similar places anywhere from 20bucks to 100. The main difference between a glasspack and a resonator is that the resonator doesn't have any of the meshing or filler in it like a glass pack but they look real similar alot of times. Basically half way between the begininng of the exaust piping and the muffler is the best place, it just getting a resonator that isn't to large and put it to close to your underside is the proplem. But they are offered in so many sizes it shouldn't be a huge problem.

MPG,

I used to have a clip, I'll see if I can find it again. Otherwise, I did finally get the beast fired back up last night and hoping to get it on the road formally by the weekend. I'll get a clip of the exhaust as soon as possible.

The turbos are barely perceivable inside the car at highway speeds (top up or down) with the dynamat installed on the floors.

Yeah, it was the drone of the flowmasters that killed me. Loved the sound at idle. Loved the sound at WOT. Hated the sound cruising around town. I sounded like a honda with neon lights. I thought about glasspacks, but was limited by space. my exhaust is completely run in the tunnel so nothing hangs down until it splits around the rear axle. Shoving glasspacks in there would have made it even tighter than it already is. It was already nearly impossible to replace the transmission when I had to do it a few years ago.

edit: I just checked, the only exhaust file I have right now is my open headers, which sound mean as hell, but definitely louder than what you are looking for...

The dreaded six drone... Here's some field research:

I'm experimenting with Hooker Dual out longtubes on a mild 170 in a '63 Wagon and a wild 250 in a '61. The 250 with full mod 250 runs Smithy mufflers. They do not drone at all at speed but are fairly raspy on WOT. In the '61 with no interior or rear seat, the Smithy sound like mild tempered open pipes. The Wagon with it's resonator shape body is a challenge. It resonated somewhat with the OEM exhaust setup. I put a glasspack in the OEM position, drove to a GG show for fun once, and took it off for the ride home to stop the headache and WHOOOOOM.... After the engine mods and Hooker dual out headers, the wagon first got generic NAPA 2" truck mufflers (thinking - way-non restrictive). The generics' sounded mild but like an old truck, so I added dual straigt-thru turbo mufflers for resonators which sounded better. For daily driver/rider contentment on the highway though, I currently run the the small OEM mufflers from the two cars on Hooker Duals' turned out in front of the wheels. The typical wagon drone is almost imperceptible (unless I concentrate :roll: ) . The headers themselves are a loud distinctive sound and dual OEM mufflers compromise works for me ...

IN PROGRESS:




Dual Hooker/ oem's:

..


SMITHY's on the '61:

I know what you're going through. Getting the "right" exhaust sound is the biggest crapshoot in the whole car hobby. The parts are expensive and you won't know if you like a set-up until it's installed.

There are just too many variables to predict the sound of a new combination. The same mufflers sound totally different on different cars, even if they have the same engine. These factors all affect the volume and harshness of the exhuast sound:
- Length of pipe before the mufflers
- Length of pipe after the mufflers
- Diameter of pipe before the mufflers
- Diameter of pipe after the mufflers

Plus, everyone's personal taste varies, so it's anybody's guess how to get something you like. As far as add-ons like resonators, tips and such, the right ones may be the answer, the wrong ones are a total waste of money. Here's another idea - I just added a crosspipe ("H-pipe") to my AMX to mellow out the Cherry Bombs, which were loud and too harsh for me. It worked wonders, but it was still a gamble.

Best bet is find an exhaust shop that understands what you are doing and will help you experiment with some different components. You won't know if you like it until it's installed and you actually hear it. I wish there was a better answer for you, but it's definitely worth the effort to get exactly what you want.

Here is a movie I posted on youtube of my mustang, a few before pics too...

The sound in the back ground is the exhaust from drving next to it, just like the begining movie. it's not from a dead stop tho.

I'm guessing the best way to do it is trial and error, well I don't have that money now... so i'll have to wait.

thanks for the Replies!!! I've learned alot about the exhaust from your replies and searches here on the forum.

Movie Clip!!!

Richard

I should have the movie clip of my exhaust up today. Got the car out last night, tuned it up (first time it's been alive since November) and got some video.

Never ceases to amaze me how well it runs despite sitting for 8 months. The only thing I do is occasionally jack up the car and rotate the tires.

Today, I need to renew the registration, fill up the tires and hopefully I'll be driving it to work by the end of the week. Need to take a few test trips around the block to make sure everything is running.

Here we go:

http://www.kastang.info/movies/exhaust.avi

note, this is @ 8*BTDC initial timing, idling around 825 RPM.

http://www.kastang.info/movies/exhaust2.avi

note, this is after the first fire up for 8 months. Timing was at 14* BTDC idling around 900RPM. I have to advance the timing if I drive it in October, else on cold mornings it tends to stall at idle for the first 5 minutes since the electric choke heats up faster than the engine does. However, this one I did a walk around, so you get an idea how quiet it is at the front of the car.

For comparison, here is the same set up with open headers. I don't seem to have one with the flowmaster 50s.

http://www.kastang.info/movies/openoz.mov

Slade

Thanks Slade!!!

I like the your idle rumble, but I also like the blatt when I rev. I guess in the end i'm just looking to stop the travel-at-speed-drone only while keeping my blatt noise at WOT...

ATM I'm running a straight through 14" magnaflows, I like the blatt it's just the drone that kills me. I did see a muffler with a spring door to kill drone but still give that blatt i'm just leary on springs inside mufflers....
DynoMax VT and youtube sound vid

here' is a sound clip of me driving down the road. http://www.youtube.com/watch?v=29ItyvaiwqI
Richard

What do you guys think of the dynomax muffler? it says lifetime warranty but I wonder long it lasts till you need the warranty...

I like the a turbo muff gives a good mellow sound. Yours sounds good have you looked for some short glass packs to add at the rear to work like a resonator?

Resonator or glass pack may be your best bet then.

But, the turbo's have a nice note at WOT. Just no drone that 'performance' mufflers seem to equate to mufflers. They may work better on a single exhaust system or a V-8, but with 3 cylinders firing per muffler, the flowmasters I had just made the mustang sound tinny and like a honda. Perhaps an X pipe would have solved it, but for me that was not really an option due to how I wanted the exhaust routed.

CobraSix":2bcbjtwg said:

Resonator or glass pack may be your best bet then.

Click to expand...

Any exhaust experts who can thoroughly describe the difference in these two?
From what I understand resonators use sound attenuation techniques to modify/muffle the tones or exhaust notes, where as a glass pack uses absorption to muffle the tones. I've also been told that glass packs (containing fiberglass type absorbing matl) wear out sooner, while resonators usually have perforated cores and act more like tuning mufflers....is this accurate?

Which would be less restrictive? Which will hold up longer? Which will do a better job of muffling or modifying drones or resonance? What difference would it make to put either of these before versus after the muffler (besides seeing more heat in the former)?

Note: It seems from the FSM info and from the oem style replacement components available, that some '66 (I assume other years as well) came with resonators stock in addition to mufflers, but on those systems it appears they necked down....from 2" to 1-3/4" for example on the dual 289 ex systems. Not sure why they did that (neck down before resonator?), and if or why they included resonators in the stock system with mufflers (used with headers or hipo system??)...tuning for specific notes or a particular sound??

Sorry Richard, hope you don't mind me aking this question under your thread, but figured this info may interest you as well. I just recently finished converting my single exhaust to full 2" front to back with the higher flowing repro of the stock 'X' manifold (2" outlet) and 68-70 2" head pipe w/ borla turbo. I'd now like to make it a little quieter similarly to what you're interested in...but without sacrificing any of the newly acquired flow gains. BTW congrats! on your build Look forward to your future dyno numbers to compare an after to your before.

Resonators are built like glasspacks, but the short length cancels out a different frequency of sound than a bigger muffler. That's the only difference. OEMs tune the resonator length to get the sound they want.