[sterling]

Hey guys I put together a magnaflow exhaust and there is just a lot of drone. Is there any way to reduce the drone? What are my options when it comes to tweaking the sound of the exhaust? Thanks

 

[cvadala7813]

What type of magnaflow setup do you have?

 

[sterling]

Two of these:
http://www.planetmagnaflow.com/shop/magnaflow-14832-427.html

And one of these:
http://www.planetmagnaflow.com/shop/magnaflow-14378-329.html

 

[Carl Wood]

I tried sound deadening material and the spray underneath the car. Nothing worked.

CW

 

[concorso]

http://www.hotrodders.com/forum/damping-exhaust-drone-resonance-131262.html

Try mounting some clamp on weights on the exhaust pipe. Theres a decent description in the link. That combined with header wrap should do the trick. Apparently this is fairly common in the hotrodding community, as they often have dual exhuast that run the length of the car next to each other, just like our CTS.

Owners with drone. What diameter of pipe are you using? If youre using the V's 2.5" piping, Id try going to a smaller diameter, as this would change the standing waves to a different level...maybe...

 

[nastymigui]

I installed two of these Street Races 14816 and I had the same drone issue at first.

http://www.magnaflow.com/02product/shopexd.asp?zone=main&id=8133

However I solved it covering the whole trunk floor (the floor and the wheel well) with dampening material. The change was remarkable and even my wife is not complaining anymore.

 

[70eldo]

http://www.hotrodders.com/forum/damping-exhaust-drone-resonance-131262.html

Try mounting some clamp on weights on the exhaust pipe. Theres a decent description in the link. That combined with header wrap should do the trick. Apparently this is fairly common in the hotrodding community, as they often have dual exhuast that run the length of the car next to each other, just like our CTS.

Owners with drone. What diameter of pipe are you using? If youre using the V's 2.5" piping, Id try going to a smaller diameter, as this would change the standing waves to a different level...maybe...

When I had my custom exhaust done there was a customer who came back to 'sleeve' his exhaust that he had done earlier. He hauls a horse trailer and the sound was too loud and made the horses nervous. So what they did was sliding a smaller diameter pipe inside the tip. I am not sure if they slid it into the muffler as well, but it worked.

 

[SvB4EvA]

When I had my custom exhaust done there was a customer who came back to 'sleeve' his exhaust that he had done earlier. He hauls a horse trailer and the sound was too loud and made the horses nervous. So what they did was sliding a smaller diameter pipe inside the tip. I am not sure if they slid it into the muffler as well, but it worked.

You may be talking about what some call "dB killers". They are basically a 6-8 inch long piece of metal, that is just slightly smaller then the exhaust diameter, that is inserted into the ends of the exhaust pipes near the tips. They will reduce the volume of the exhaust slightly and not change the sound of it much. It is very cheap to install these and may be worth a try.

Another option is resonator tips on the exhaust, same concept as the "dB killers" but slightly more expensive and will cancel out sound waves to slightly reduce volume and reduce the hum or drone.

Keep in mind, mufflers muffle sound, usually by fiberglass/steelwool packing to absorb sound waves. Resonators are designed to make sound waves bounce around to "cancel each other out". You can tell what a muffler is and a resonator usually by just flicking your finger nail off of one. A muffler will make a "thud" sound because it is packed with steelwool/fiberglass, where a resonator will make a "ping" sound, because it is hollow inside.

Then of course, there are "mufflers" they have the properties of both a muffler and a resonator, ie, chambered mufflers.

The stock setup on the CTS is a combination of a resonator and 2 chambered mufflers (on dual exhaust CTSs).