REDUCING drone! (NOT eliminate)

[Chewy]

That's right folks, I set out to reduce the drone that an aftermarket system transmits into the car. I knew going in with exhaust that the dreaded drone would raise its ugly head but I wanted an exhaust note and since the stock system is void of all sound I went with the Magnaflow system and am VERY happy with the result. VERY!:first:

So yesterday and today I set in on the car with about 160 dollars worth of Dynamat extreme and started covering the trunk areas. I covered a lot of but not all of the spare tire well with it and then set off on covering the area right above the mufflers and the rest of the trunk floor. Last night I got my G/F in the car and told her what I did. Keep in mind she is SOOOO NOT a car person and usually doesn't notice anything but she noticed straight away how much quieter the car was around the dreaded 2000 RPM range. Today I set off on the wheel wells and deck lid to help even more. I also placed about 5-6 towels in the spare tire well to help absorb sound.

The difference is amazing and I HIGHLY recommend it to those wanting to reduce the drone a bit. I'd say it's reduced it by 40-50%.

Here's the pics of the trunk.


Cheers all,
Chris

[GeorgeInNePa]

What if you put it on the bottom of lift out piece that covers the spare tire well/trunk floor? You could put a few layers on it.

That way you could lift it out and remove the weight when you want to.

[Chewy]

What if you put it on the bottom of lift out piece that covers the spare tire well/trunk floor? You could put a few layers on it.

That way you could lift it out and remove the weight when you want to.

The weight is negligible and I am not looking for a stupid fast car anyway. The weight is mostly low in the car so no worries with handling. Dynamat has to be attached to the metal or plastic to keep resonance down. It's amazing the results I have had.

If you're looking for the ultimate in speed at the track and don't care about internal noise then don't do this mod. My rear passengers were a bit numbed by the sound. NOT anymore!

I'd say that I am still under the weight of the car with the stock exhaust on it.

Chris

[wreckwriter]

I wish that shit wasn't so pricey. Take a guess on the weight for what you have on there now please.

[Chewy]

I wish that shit wasn't so pricey. Take a guess on the weight for what you have on there now please.

12 pounds?

I would guess 3lbs per roll maybe. Well worth the slight increase in weight. The towels are maybe 2 pounds...

Also if you tighten the compressor kit down good 'N tight that helps too!

[wreckwriter]

That's not bad. The stuff self sticks, peel off backing, right?

[Chewy]

That's not bad. The stuff self sticks, peel off backing, right?


Correct! I didn't completely cover ALL the metal back there but instead covered the metal and plastic near the mufflers and then here and there over the rest of the trunk. I got my fat A$$ up inside that bad boy and damn near couldn't get out! LOL

[AusTXGT]

That's right folks, I set out to reduce the drone that an aftermarket system transmits into the car. I knew going in with exhaust that the dreaded drone would raise its ugly head but I wanted an exhaust note and since the stock system is void of all sound I went with the Magnaflow system and am VERY happy with the result. VERY!:first:

So yesterday and today I set in on the car with about 160 dollars worth of Dynamat extreme and started covering the trunk areas. I covered a lot of but not all of the spare tire well with it and then set off on covering the area right above the mufflers and the rest of the trunk floor. Last night I got my G/F in the car and told her what I did. Keep in mind she is SOOOO NOT a car person and usually doesn't notice anything but she noticed straight away how much quieter the car was around the dreaded 2000 RPM range. Today I set off on the wheel wells and deck lid to help even more. I also placed about 5-6 towels in the spare tire well to help absorb sound.

The difference is amazing and I HIGHLY recommend it to those wanting to reduce the drone a bit. I'd say it's reduced it by 40-50%.

Here's the pics of the trunk.


Cheers all,
Chris

This is great news. I looked at dynamat but without knowing how effective it would be the price was to high. How many square feet in a roll?

[caretaker]

Amazon has bulk packs of Dynamat 10455 Xtreme for $134
with free shipping. 9 pieces - 18" x 32 " - 36 sq. ft.

[Chewy]

This is great news. I looked at dynamat but without knowing how effective it would be the price was to high. How many square feet in a roll?


Amazon has bulk packs of Dynamat 10455 Xtreme for $134
with free shipping. 9 pieces - 18" x 32 " - 36 sq. ft.

That's about 20 less than Best Buy was for that one. I used 16 sqft of it.

The trunk could eat over double that in a heart beat but I just did what I deemed important.

4sqft per roll the way I bought it. If I knew then what I know now I would have bought the bigger roll of it! :eyeroll:

Chris

[Mlozano]

Bump... anyone else get results from this

[adriand]

You think the spray on sound deadener would have the same effect?

[Chewy]

You think the spray on sound deadener would have the same effect?
As long as you could get it on thick enough. A lot of times the spray stuff stinks. As long as you only used it outside I'm sure it'd be OK.

Chris

[locrzn#92]

Cortex tuner will eliminate any drone.

[SRG963]

Cortex tuner will eliminate any drone.

LOL, it does make the car purr. No more ruff idle :)

But a bad muff setup can make any car with any tune drone.

[SLVRG8GT]

Cortex tuner will eliminate any drone.
I really hope that sarcaism :devil:

[drewcifer]

It's hard to find mufflers that won't drone in the stock placement, but some good straight throughs like dynomax ultraflo muffs will make all drone disappear. They don't add weight or stank like sound deadener and they flow better than damn near anything else you'll find.

[Chewy]

Not sure about that... My Magnaflows are straight through. The reasons are due to the removal of the resonators. People with resonators aren't having as large of an issue.

[99-LS1-SS]

I coated my trunk with Dynamat yesterday and it really didn't make much difference in the sound. I even laid 2 blankets in the wheel well.

[Chewy]

I coated my trunk with Dynamat yesterday and it really didn't make much difference in the sound. I even laid 2 blankets in the wheel well.

Mine took the edge off it.

[99-LS1-SS]

Maybe my edge is too much for it to really affect.

[Chewy]

Yeah it's not going to remove it. Only talk the edge off. My Fiance' noticed straight away.

Chris

[G8V8]

I put 2 layers over the muffler area and across the vertical area between the tail lights. I put 1 layer on the rest of the trunk floor and a little on the spare tire well ( just the sides facing the mufflers. I put some on the wheel wells and coated the entire vertical wall behind the rear seat back. I also pulled the back seat bottom and put some on the floorpan back there. It made quite a difference.

[billyb21]

ima lazy f--- ill just use the sport/manual mode dont get the drone with my ride to work i dont get past 4th gear

[billyb21]

but a good idea though

[Chewy]

Not sure what exhaust you have but mine has drone no matter if it's in sport of manual DOD or not. It drones... I don't mind it but it doesn't go away or become less in one or the other in my car.

[Paniller]

You guys think a gallon of eDead will do me? Or should I get some foam stick-on sound proofing as well?

[Paniller]

Ok, I painted up the entire trunk with eDead, and also the base of the rear seat. I'll see how it is on the way to work tomorrow. Then I'll come home and reinstall the seats and such, taking some more pictures. Then weds is the true test, a 1-hour ride to go get an H-pipe installed.

I'm guessing I'll need a second layer, or some of the thicker foam type on top of it. It's pasted on pretty thin in some places. I'm thinking another gallon for the trunk and floor, and some thick matting covering the back seat, under the back section. One side paste, one side mat. That should kill Mr. Drone.

[RB Designs]

I did mine with Hushmat.........big differance.

[jbradsh1]

I did mine with Hushmat.........big differance.

I bought a fair amount of Hushmat, on your recommendation actually, but haven't installed it yet. Any tips about how and where to install for a quieter car?

[RB Designs]

I did the whole trunk floor, well area, inner fenders, under back seat
and the trunk wall, under package shelf........wifey is happy now :)

[jbradsh1]

I did the whole trunk floor, well area, inner fenders, under back seat
and the trunk wall, under package shelf........wifey is happy now :)

Thanks.

[08hotwhtgt]

Hi..I am interested in using this hushmat to quieten my drone as well...could u tell me how many sheets or square ft of this stuff I should order? thanks

[jboogie]

For u guys on a budget home depot and lowe's sells a roofing product called "Peel & Seal". This stuff is very comparable to dynomat and other aluminum faced butyl products. The butyl products will only cut down on the cars metal parts vibrating and producing noise. I wouldnt recomend using this stuff on anything that will be hanging upside down but in the trunk it works great!

U will also need a closed cell foam to reduce the amount of sound coming into the vehicle from outside. The closed cell foam is the key to lowering the sound u dont want in the car. The combination of both of these products will give u the best results.


J.

[ddale70]

I had great results on my 2006 GTO using a product called eDead, less expensive than Dynamat. Can be purchased by the sq. ft. I ran a JBA cat back system and the drone was awful. Ended up covering trunk, wheel wells, doors, etc... What a difference it makes, check the web for articles on how best to apply it.

[jbradsh1]

U will also need a closed cell foam to reduce the amount of sound coming into the vehicle from outside. The closed cell foam is the key to lowering the sound u dont want in the car. The combination of both of these products will give u the best results.
J.

Sounds like a good idea. Is this the expandable foam in cans you can get at Home Depot or Lowes? And where would you put the stuff? Thanks.

[GeorgeInNePa]

Sounds like a good idea. Is this the expandable foam in cans you can get at Home Depot or Lowes? And where would you put the stuff? Thanks.

Examples:

http://www.closedcellfoams.com/

[jbradsh1]

Examples:

http://www.closedcellfoams.com/

Thanks George, good site.

[Darkside]

Examples:

http://www.closedcellfoams.com/

Nice link George, I actually just placed a big order with them yesterday. If you read their site, all their noise and accoustic foams are open cell foams.

[jbradsh1]

I've decided to use the Hushmat on the back seat bottom & back rather than the trunk, to start with. See if that helps first before I apply it all over the trunk area.

[learjet60]

Has anyone used any of the sound deadeners on a their GT that still has its stock exhaust, or is that pointless?

[NYG8GT]

Completely pointless with a stock exhaust, or even an exhaust with no resonators but stock mufflers. You dont get drone until you replace the stock mufflers ;)

[Devilish34]

Completely pointless with a stock exhaust, or even an exhaust with no resonators but stock mufflers. You dont get drone until you replace the stock mufflers ;)

I have MF axle backs and found the best way to eliminate/reduce drone is drive over 80 mph.. The car really quiets down then but if AFM kicks on :spank: ugg it's annoying

[Chewy]

Has anyone used any of the sound deadeners on a their GT that still has its stock exhaust, or is that pointless?

Pointless no... It will help eliminate other noises. One guy stripped his entire stock G8 down to the floor pans, head liner, and doors and covered EVERYTHING with it.

THAT car had to be quiet but it adds a lot of weight too. He was going for a high quality sound system and not speed.

[Darkside]

I want to add that my foam project didn't do dick. Thank you, carry on.

[08hotwhtgt]

Ditto! I order this stuff from smittymats.com ..its a self stick Closed cell dense vinyl foam with aluminum foil backing. dynamat or hushmat comparable.I lined my whole trunk ..spare wheel well.. entire floor ...underside of the trunk ...package shelf..behind the rear seat..and the the sides ..still have drone ...ughhh! here are some pics ..thought it was gonna actually work...any other ideas other than shelling out 1400.00 for the corsa system..wish the mufflers for the system could be purchased alone....anyone?

[jbradsh1]

Ditto! I order this stuff from smittymats.com ..its a self stick Closed cell dense vinyl foam with aluminum foil backing. dynamat or hushmat comparable.I lined my whole trunk ..spare wheel well.. entire floor ...underside of the trunk ...package shelf..behind the rear seat..and the the sides ..still have drone ...ughhh! here are some pics ..thought it was gonna actually work...any other ideas other than shelling out 1400.00 for the corsa system..wish the mufflers for the system could be purchased alone....anyone?

Yes, get LT headers, a cai, and use the stock mufflers. It will be plenty loud when you get on it but no drone or much noise until you do.

[woody]

I had my local muffler shop build me a set of Active noise cancelling chambers. Now what they made me did not remove all of the drone (50-70%)but I can now ride in the car again with out getting a headache. I think this setup could remove all the drone with some adjustments but for me its just about good enough.

[menace]

There are systems now in Aus that have 0 Zero Drone. They are not cheap just like the Corsa systems.

If interested search ls1.com.au

BTW. Drone is cause by the exhaust length and mufflers used. They had the same problem here where companies did not road test the vehicles. Apparently allot of it is controlled by what mufflers you use. If you cheap out you get drone.

Woody: Great thinking on the chambers, would an addition of another chamber on the other side help you think?

Any loss in power?

[r33pwrd]

There are systems now in Aus that have 0 Zero Drone. They are not cheap just like the Corsa systems.

But do they have DOD?

[menace]

But do they have DOD?

DOD is not the cause of the drone.

They have just been released with DOD now...

[r33pwrd]

DOD is not the cause of the drone.

They have just been released with DOD now...

Not the cause? have you ever drive a G8 without muffler and heard it when the DOD kicks on? It is not the only factor but a big pain in the ass when trying to reduce drone.

[woody]

I have the chambers on both sides and I would say that this would be the best solution over dynamat,foam,rubberizing,insulation,or any type of sound deadening products on the market. This design removes the drone the same way the corsa mufflers would but leaves you with the choice of which brand you like. With this setup I can have my radio at 7 and drown out the drone also anything over light acceleration removes the drone all together.

[menace]

Ok point taken, but the Commodores here have the same drone problems without DOD. So it can't be solely blamed on it.

[jimjones]

Ditto! I order this stuff from smittymats.com ..its a self stick Closed cell dense vinyl foam with aluminum foil backing. dynamat or hushmat comparable.I lined my whole trunk ..spare wheel well.. entire floor ...underside of the trunk ...package shelf..behind the rear seat..and the the sides ..still have drone ...ughhh!


I hate to see post like this as no product on the market can stop exhaust drone.
It is an ubar low frequency noise created by a flawed exhaust system that 6ft of granite would not stop. Think if it as a big bass speaker under your car or in your car. Until you open the door you won’t hear any mid or high range stuff, but the low bass beat will be heard regardless. The only fix for exhaust drone is a new exhaust, and exhaust drone is a flaw in design you do not want on your car n e ways. You need to put blame where its meant to be. You tried to Band-Aid a problem instead of fixing it right. No sound material will stop exhaust drone. Call who ever made the muffler and exhaust system if it’s a cat back type system. They may have an answer for you.
I just fixed a drone on mine by adding 2ft of tail pipe on my Z.

Think of the muffler as the mouthpiece, the tail pipe is the horn.
You can sometimes adjust the horn.

[fourthmeal]

Looks like a few brands need to be brought up to the GRRRR8 crew...

www.secondskinaudio.com

At the DIYMA forum, you'll see a lot about this stuff. Generally the best you can buy, and costs less than Dynamat Xtreme.

And for an economical solution, www.raamaudio.com. RAAMmat and Ensolite are some of the best values in sound deadening known to the DIYMA community.

You should ideally deaden (mass-load) panels w/ a butyl-foil product, then do either a vinyl barrier or at least a closed-cell foam barrier.

Also, don't use PEEL&SEAL. It isn't butyl, it is asphalt (unless they came up w/ something that I don't know, which is possible.) Asphalt will melt off, unstick, and generally suck pretty bad. Beware.

[GXPaycheck]

I have noticed that there appear to be 2 different definitions of drone. One is a vibration that occurs at certain RPM's, and the other is the sound caused by the AFM going on and off. Helps sometimes to differentiate between the two when posting.

[cvidt]

I was wondering if anyone here installed the oem factory cargo mat?
Thats one giant piece of form fitting rubber for the floor. I thought that might help. I want to get one even if its just to protect the carpet. http://www.gmaccessorieszone.com/Pontiac/2009/G8/Cargo%20Tray/?src=pontiac&tx_gmshopb2b_pi1[type]=gm

[Chewy]

I was wondering if anyone here installed the oem factory cargo mat?
Thats one giant piece of form fitting rubber for the floor. I thought that might help. I want to get one even if its just to protect the carpet. http://www.gmaccessorieszone.com/Pontiac/2009/G8/Cargo%20Tray/?src=pontiac&tx_gmshopb2b_pi1[type]=gm

I haven't.

I tempted to replace my muffs or have some drone eliminators welded on to them.

Chris

[BigRed585Lbs]

http://www.autocarepronews.com/Article/70421/dynomax_introduces_revolutionary_dronefree_muffler .aspx

And that's the name of that song.

[Adam]

Putting it under the butt portion of the back seats is where you will cut a lot of the noise down! The trunk helps some for the noise that drones through the rear speaker shelf but pop the rear seat bottom out and put a layer in and tell me that does not make a difference. It is where a lot of the drone came from on my Trans Am's and any other V8 I have owned.

[piecesparts]

I did the whole enchilada with the mat in the truck. I also lined inside the spare wheel area. I took the plastic inner wheel wells off of the car and undercoated the sheetmetal behind them (this changed things quite a bit by the way). I also sprayed under coat on the outside of the spare housing and the rear bumper area. I even made an insulated cover piece that goes across the opening from the trunk to the interior of the car, so that when passengers are using the fold down arm rest/cup holders, the noise from the exhaust and the wheels is not transmitted to the front. When the armrest is down the opening is still covered inside the trunk.
The removal of the center muffler and replacing it with an X-Pipe made the biggest difference of all. At the same time of the X-pipe install, we moved the muffler tips from the Magna-flow muffs as far back as we could by moving the mufflers back on the original mounting rubber hangers. This got the shorter MF tips a little further out from under the bumper than they were when I frist put the new mufflers on the car. The noise is now at the back of the car, like it should be and the sound is more of a rumble like a sports car, instead of a hollow noise right at your ear. I like the sound of the G8 now and wish I had the X-pipe done earlier.

[mot76]

I,too, installed Magnaflow axlebacks to my car and love the sound at open throttle. But the drone around town, not so much. I lined the trunk floor, including the spare tire well, with Fat Mat trunk kit I purchased from Ebay. It's about 1/2 the price of Dynomat. I didn't line the seatback, under the rear seat nor the rear speaker shelf. Then, I got some 1/2" carpet padding from Home Depot and cut a piece to resemble trunk mat. I placed the padding under the trunk mat. I even added some extra inside the spare tire well. All of this helped the drone but it's still there. I was hoping for better results. Maybe, I'll try to put something under the rear seat if it's not a pain to remove.

[Adam]

Looks like a few brands need to be brought up to the GRRRR8 crew...

And for an economical solution, www.raamaudio.com. RAAMmat and Ensolite are some of the best values in sound deadening known to the DIYMA community.
.

+1 great stuff. The new products are better then some of the products double the price. Great quality at a more entry level price. I have used MANY brands in the past and would stick with raamaudio from now on.

[cvidt]

So after reading all these sound deadening posts whats the verdict? For the guys that did it would you do it again?
Some people see a big difference others not so much... I'm just trying to figure out what to do.

[Adam]

You can spend a ton of money and buy a soundproof car. You can deal with the noise levels in your car. Or you can use the sound deadener to help with the noise. It will not get rid of all the noise but it will really cut down the cabin noise a ton. You will still know you have a V8 when you give it the gas, but it will be more timid inside at cruising speeds.

[Marc Letourneau]

After reading this thread I have reconsidered buying Axle backs for my G8. I think I may just take the Corsa route, I have heard many good things about them and it may be worth the money so I don't have to listen to the drone.
Any advice or information please feel free to tell me.

[mark]

After reading this thread I have reconsidered buying Axle backs for my G8. I think I may just take the Corsa route, I have heard many good things about them and it may be worth the money so I don't have to listen to the drone.
Any advice or information please feel free to tell me.

I replaced my magnaflow axle backs with the solo axle backs that have the "J" bend in them. This has eliminated any drone issue I had with the magnaflows. Look into the solos if you want a no drone option. I think they sound better than the magnaflows too. The J bend seems to be the only true fix for the drone issue. Everything else(sound deadening, etc.) treats the symptom and not the problem.

[BigRed585Lbs]

Band-aids, not cures, huh?

[Marc Letourneau]

I replaced my magnaflow axle backs with the solo axle backs that have the "J" bend in them. This has eliminated any drone issue I had with the magnaflows. Look into the solos if you want a no drone option. I think they sound better than the magnaflows too. The J bend seems to be the only true fix for the drone issue. Everything else(sound deadening, etc.) treats the symptom and not the problem.

Don had brought to my attention about Solo yesterday I think. You are the first I have been able to talk to that actually has them. Good to know that you do like them and I also really like the fact that they come with 3.5 inch tips to fit in the GXP diffuser nice.