Drone Resonance and more Droning Thread
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Originally Posted by rodybmw' post='506531' date='Dec 13 2007, 04:42 PM
...........
Jay,
If the Remus Center mufflers(in place of the OE Boxed Resonator) with two straight pipes going to the tips ends up with some droning then I would add two small round resonators (not oval mufflers) in the back where the original muffler was and the 5" space on the right side.
[b]Well--wouldn't you know it. You two guys(Quy and Rody)know your shit. After driving my beast all day the Droning at the 1-2k level is annoying for passengers in my car. I'm ready to get rid of it. What "two small round resonators" would work best on the right and left side? Where can I look on the net for them?
[/b]
You already know that I'm getting the Remus quad for the I6's installed on my car (hopefully tomorrow). However, if later on I decide that I want a balanced output from both the right and left side I would go with the Remus 545/550 in the center with or without tube resonators at the back.....depending on whether there is some droning or not after removing the center resonator.
Rody--I know you're good with your set-up(I think it's great), but if you decide to change at some point, hopefully my set-up(Cats--Stock OE Tube Resonators--X-Pipe--2 4.5 Remus Round Cans--Straight Pipe--"2 Small Round Resonators on Left and Right Side"--Tips)will be your prototype to work off?
Does anyone know if it matters what order each component goes in? What I mean is that in the oem setup the resonators always come before the muffler.....would it be OK to have it the other way around with the muffler in the middle and the resonators coming AFTER the muffler? So the complete setup being the two tube resonators up front, then a muffler in place of the box resonator in the middle, and then another set of tube resonators at the rear?
Jay,
If the Remus Center mufflers(in place of the OE Boxed Resonator) with two straight pipes going to the tips ends up with some droning then I would add two small round resonators (not oval mufflers) in the back where the original muffler was and the 5" space on the right side.
[b]Well--wouldn't you know it. You two guys(Quy and Rody)know your shit. After driving my beast all day the Droning at the 1-2k level is annoying for passengers in my car. I'm ready to get rid of it. What "two small round resonators" would work best on the right and left side? Where can I look on the net for them?
[/b]
You already know that I'm getting the Remus quad for the I6's installed on my car (hopefully tomorrow). However, if later on I decide that I want a balanced output from both the right and left side I would go with the Remus 545/550 in the center with or without tube resonators at the back.....depending on whether there is some droning or not after removing the center resonator.
Rody--I know you're good with your set-up(I think it's great), but if you decide to change at some point, hopefully my set-up(Cats--Stock OE Tube Resonators--X-Pipe--2 4.5 Remus Round Cans--Straight Pipe--"2 Small Round Resonators on Left and Right Side"--Tips)will be your prototype to work off?
Does anyone know if it matters what order each component goes in? What I mean is that in the oem setup the resonators always come before the muffler.....would it be OK to have it the other way around with the muffler in the middle and the resonators coming AFTER the muffler? So the complete setup being the two tube resonators up front, then a muffler in place of the box resonator in the middle, and then another set of tube resonators at the rear?
VT(Joe)---How in the world did you get "no droning" with your RDS Exhaust when you deleted all 3 resonators? FedCaper---What about you with your RD Sport?
Thanks Guys!
So Cal
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Originally Posted by tbal' post='509844' date='Dec 23 2007, 02:46 AM
ivan545 got any sound clips.. anyone else of soundclips?
I have 2 round 4" resonators (cherry bombs, glasspacks, small mufflers, whatever you want to call them) at the rear, and it will NOT get rid of your droning unless your Remus 4.5" are some magical canisters or baffled (I am assuming they're straight throughs). I've got a sound clip on my camcorder that records the droning on my vehicle. Let me find some time to edit it and post it.
4.8L is a big engine. 4 resonators alone, will not eliminate your droning. As for the TQ loss, you may noticed your rpm going a little higher for you to feel the "oomph." The sound note can either be interpreted as performance or as engine strain. Either way, your engine breaths better than before in conjunction with your CAI.
Was the exhaust note too exciting to add the oval turbo mufflers at the rear?
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Originally Posted by SoCalM5Mang' post='509837' date='Dec 23 2007, 01:31 AM
QUY---What about Rody's question here? I guess I'll be putting her to the test when I go back to Triple AAA on Wed or Thursday to add some right and left side resonators.
VT(Joe)---How in the world did you get "no droning" with your RDS Exhaust when you deleted all 3 resonators? FedCaper---What about you with your RD Sport?
Thanks Guys!
So Cal
VT(Joe)---How in the world did you get "no droning" with your RDS Exhaust when you deleted all 3 resonators? FedCaper---What about you with your RD Sport?
Thanks Guys!
So Cal
#55
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Originally Posted by Bimmer32' post='510173' date='Dec 24 2007, 05:42 AM
There's plenty of sound clips on previous threads in the Parts Dept. (subforum). I guess somebody could create an Official Exhaust Mod Thread.
I have 2 round 4" resonators (cherry bombs, glasspacks, small mufflers, whatever you want to call them) at the rear, and it will NOT get rid of your droning unless your Remus 4.5" are some magical canisters or baffled (I am assuming they're straight throughs). I've got a sound clip on my camcorder that records the droning on my vehicle. Let me find some time to edit it and post it.
4.8L is a big engine. 4 resonators alone, will not eliminate your droning. As for the TQ loss, you may noticed your rpm going a little higher for you to feel the "oomph." The sound note can either be interpreted as performance or as engine strain. Either way, your engine breaths better than before in conjunction with your CAI.
Was the exhaust note too exciting to add the oval turbo mufflers at the rear?
I have 2 round 4" resonators (cherry bombs, glasspacks, small mufflers, whatever you want to call them) at the rear, and it will NOT get rid of your droning unless your Remus 4.5" are some magical canisters or baffled (I am assuming they're straight throughs). I've got a sound clip on my camcorder that records the droning on my vehicle. Let me find some time to edit it and post it.
4.8L is a big engine. 4 resonators alone, will not eliminate your droning. As for the TQ loss, you may noticed your rpm going a little higher for you to feel the "oomph." The sound note can either be interpreted as performance or as engine strain. Either way, your engine breaths better than before in conjunction with your CAI.
Was the exhaust note too exciting to add the oval turbo mufflers at the rear?
I've been driving it more and I'm concerned some of the pipe bracketing in the center of the car has come loose? There is an annoying rattling sound/vibration when rolling over bumps/potholes-uneven road surfaces. It also vibrates at start-up and putting in reverse? I'm going back to Triple AAA on Wednesday to have it checked out.
Any idea what this might be? This was not happening the first two days. I was riding around surface streets on Saturday and it started happening yesterday. Maybe hitting a pot hole or something knocked something loose?
Merry X-Mas to everybody!
So Cal
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Originally Posted by SoCalM5Mang' post='510309' date='Dec 24 2007, 05:13 PM
Hi Quy! If I add the Turbo Mufflers at the rear will it help with Torque Loss?
I've been driving it more and I'm concerned some of the pipe bracketing in the center of the car has come loose? There is an annoying rattling sound/vibration when rolling over bumps/potholes-uneven road surfaces. It also vibrates at start-up and putting in reverse? I'm going back to Triple AAA on Wednesday to have it checked out.
Any idea what this might be? This was not happening the first two days. I was riding around surface streets on Saturday and it started happening yesterday. Maybe hitting a pot hole or something knocked something loose?
Merry X-Mas to everybody!
So Cal
I've been driving it more and I'm concerned some of the pipe bracketing in the center of the car has come loose? There is an annoying rattling sound/vibration when rolling over bumps/potholes-uneven road surfaces. It also vibrates at start-up and putting in reverse? I'm going back to Triple AAA on Wednesday to have it checked out.
Any idea what this might be? This was not happening the first two days. I was riding around surface streets on Saturday and it started happening yesterday. Maybe hitting a pot hole or something knocked something loose?
Merry X-Mas to everybody!
So Cal
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As for the sound/vibration, those Remus canisters look a bit tightly confined in those spaces. I could only guess that it's the canisters or a hanger or 2 come loose or hang too close.
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#57
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Originally Posted by Bimmer32' post='510396' date='Dec 24 2007, 09:52 PM
If anything, the turbo mufflers will help quiet down the sound level; with the sound level down, your butt dyno may feel some reclaimed torque.
Sure, turbo mufflers help with low end torque. I thought you were going to re-install the OE center resonator box and turbo mufflers at the rear? Hopefully, those AAA won't charge you additional for installing the mufflers in the rear.
As for the sound/vibration, those Remus canisters look a bit tightly confined in those spaces. I could only guess that it's the canisters or a hanger or 2 come loose or hang too close.![Whistling](https://5series.net/forums/images/smilies/imported/whistling.gif)
![Big Grin](https://5series.net/forums/images/smilies/imported/biggrin.gif)
As for the sound/vibration, those Remus canisters look a bit tightly confined in those spaces. I could only guess that it's the canisters or a hanger or 2 come loose or hang too close.
![Whistling](https://5series.net/forums/images/smilies/imported/whistling.gif)
I will see what Triple AAA recomends but it's gotta get fixed. There is definitely heat coming from the piping. When I stick my hand outside of the car(passenger side)at a light, I feel pretty intense heat coming from the back(I suppose).
If I have them re-install the Center OE Resonator Box---where would they do it? The two Remus Canisters are right where it used to be. Install right before them and then the Turbo Mufflers in the back? What exact mufflers are you using in the back left and right? I need to make sure they fit completely with no hang.
Thanks bro.
Jay C
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Originally Posted by vegastrashed' post='508943' date='Dec 20 2007, 03:49 PM
Great.... I found a website that shows an example of a cherry bomb muffler and it looks exactly like a bullet resonator! I give up. The stock resonator is going back on.
http://auto.howstuffworks.com/muffler5.htm
http://auto.howstuffworks.com/muffler5.htm
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Originally Posted by SoCalM5Mang' post='510411' date='Dec 25 2007, 02:47 AM
Merry X-Mas Quy!
I will see what Triple AAA recomends but it's gotta get fixed. There is definitely heat coming from the piping. When I stick my hand outside of the car(passenger side)at a light, I feel pretty intense heat coming from the back(I suppose).
If I have them re-install the Center OE Resonator Box---where would they do it? The two Remus Canisters are right where it used to be. Install right before them and then the Turbo Mufflers in the back? What exact mufflers are you using in the back left and right? I need to make sure they fit completely with no hang.
Thanks bro.
Jay C
I will see what Triple AAA recomends but it's gotta get fixed. There is definitely heat coming from the piping. When I stick my hand outside of the car(passenger side)at a light, I feel pretty intense heat coming from the back(I suppose).
If I have them re-install the Center OE Resonator Box---where would they do it? The two Remus Canisters are right where it used to be. Install right before them and then the Turbo Mufflers in the back? What exact mufflers are you using in the back left and right? I need to make sure they fit completely with no hang.
Thanks bro.
Jay C
1. The heat - all cars have heat eminating from the bottom. The radiator fan usually blow heat under the car. As for the piping, exhaust gas are very hot, so of course, the pipes will be hot. There are OE heat shields until you get to the back right side. As long as the pipes and/or resonators/mufflers are not touching any walls or compartment, you should be OK.
2. The OE center boxed resonators go where your remus canisters are now. If you want to try your luck again, you can install the canisters at the rear. Warning: I would expect droning to continue. I serious think the stock OE resonators only lower the sound level by 2-4 db and at certain frequencies (usually 90 hz range). So goes the same for the Remus canisters.
As I said before, I'm using two 4" round magnaflows (one on each side). And the droning is unbearable for a 5er type car after a couple of weeks. My cheap fix (mod) is stuffing SS wool to muffle the sound down. It's working so far. This mod is like using Turbo mufflers. I will change to turbo muffs if and when I'm tired of my cheap but effective mod.
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Originally Posted by vegastrashed' post='510495' date='Dec 25 2007, 02:50 PM
I've been doing a lot of research and I truly believe that bullet resonators are not glass packs (cherry bombs) and that they will minimize, if not eliminate, droning. I'm going forward with this when I get back to the Bay Area.
A quick review of terms:
1. Mufflers - a device that muffles or reduces sound level (usually use to eliminate or reduce low frequencies) from an exhaust system
2. Resonators - a device that muffles or reduces sound level (usually tuned to eliminate or reduce higer frequencies) but not as effective as a muffler. It is also used to "tune" an exhaust sytem to give it a certain sound and the size is smaller than a muffler.
Mufflers and resonators are used synomymously, but mufflers usually mean a bigger device than a resonator. Technically, a resonator is called a resonator because it is designed to "tune" a certain note from the exhaust noise.
Cherry bombs were so called in the 50s, 60s, and 70s. Then people began to call them glasspacks . . . later bullets. I think that's the order, but someone correct me if I'm wrong. In any case, they all have similar design and purpose.
1. A straight-through perforated pipe. Pipe size and perforation degrees may vary.
2. Cover with SS wool and/or fiberglass and encased. Amount of SS wool and/or fiberglass used may vary.
If it's a tube and fat in the middle, it's a cherry bomb/glasspack/bullet muffler/resonator. For example, I have a 4" O.D (outer diameter) with a 2.25" I.D. (inner diameter) pipe. That give me about 2+ inches circumference volume of SS wool/fiberglass for sound absorption. The size allow me to fit it in small places. It's a resonator by design, but can be called a muffler because it has some absorptive material inside. Cherry bombs/glasspacks/bullets have even smaller amount of absorptive materials.