Side Branch Resonator

phi1542 · Jun 2, 2015

Re: Getting rid of exhaust drone?

spacemonkee23 said:
This is the video where I heard the "further forward" bit from, there were also some random forums that suggested the same information. Nothing concrete to prove there is a big difference on where its installed though. It makes sense to me if you are going to do it yourself you can choose where is best. I'd say the location in your drawing is ideal because the cat will alter some of the sound waves then the Helmholtz to cancel the frequency along with the inline resonator to absorb any drone that is left over.

Makes sense LOL I'll just throw it there. Plus its going to be long so I need to make sure there's enough space and having it there will give me plenty of room.

truWarier02 · Jun 4, 2015

Re: How to eliminate exhaust drone step by step

Yep, they're Helmholtz resonators and I've only found that out after moving on to the Genesis. There's an axleback by Nameless Performance that is muffler-less with helmholtz resonators and only utilizes the factory single pipe catback. One of the best sounding exhausts for the Gen platform, period.

Sounds as crazy as it looks.

phi1542 · Jun 4, 2015

Re: How to eliminate exhaust drone step by step

truWarier02 said:
Yep, they're Helmholtz resonators and I've only found that out after moving on to the Genesis. There's an axleback by Nameless Performance that is muffler-less with helmholtz resonators and only utilizes the factory single pipe catback. One of the best sounding exhausts for the Gen platform, period.

Sounds as crazy as it looks.

That sounds awesome...... :drool:

Yeah helmholtz is different though. Similar but more complicated since they use volume. The picture has a can like resonator rather the 1/4 wavelenth, branch, or j pipe resonator whatever you want to call it lol is just a pipe and the main thing is length rather than the volume.

So its basically straight pipe after market? Thats awesome haha I like the one you have on yours better though. It has a better tone to it.

My exhaust is kind of like that. I have a full straight pipe cat back with 18" dynomax resonator and I just got the 39" side branch resonator done today. No mufflers and it sounds like a beast. Awesome rumble and no drone. Perfect. Its loud enough where I can hear the exhaust and the purr but no annoying drone. I couldn't be any happier with my exhaust. I love it haha

UPDATE: THE SIDE BRANCH THING ACTUALLY WORKED!!!!!!! Updated OP

johnnxiv · Jun 5, 2015

Re: Getting rid of exhaust drone?

spacemonkee23 said:
It quieted it down a little but I am not for loud exhaust any more. Here is a clip, sounds best with headphones or speakers with a sub.

How low is thi sin person? I always here good things about Magnaflow.

spacemonkee23 · Jun 5, 2015

Re: Getting rid of exhaust drone?

johnnxiv said:
How low is thi sin person? I always here good things about Magnaflow.

It's pretty quiet and low with the setup I have. Practically no raspy sound and zero drone. Because of this thread I now have plans to put in a cable or electric operated cut out for when I want it loud. Prob won't happen for a while but I do have a Welder, exhaust tubing, extra flanges from when I did my old truck exhaust and an old throttle body. I might try and make it work right at the a Y split.
Love the MagnaFlows btw.

spacemonkee23 · Jun 5, 2015

Re: How to eliminate exhaust drone step by step

phi1542 said:
UPDATE: THE SIDE BRANCH THING ACTUALLY WORKED!!!!!!! Updated OP

Any video clips of how it sounds, outside and inside while driving?

phi1542 · Jun 5, 2015

Re: How to eliminate exhaust drone step by step

spacemonkee23 said:
Any video clips of how it sounds, outside and inside while driving?

Not yet haha but ill post some up asap!

phi1542 · Jun 5, 2015

Re: How to eliminate exhaust drone step by step

spacemonkee23 said:
Any video clips of how it sounds, outside and inside while driving?

Posted up videos of inside the cabin while driving around my area and some outside revs.

I think I still need to do some fine tuning with the resonator though. At first when I'm driving no drone but after a while when it gets more hot then there is a little bit a drone. I took the video when it got hotter so drone was more noticeable. My original calculations were at 240 deg F but now I remeasured it when the exhaust was more warmed up and hot i got about 340-350 deg F. I think I got my drone wrong too. It's somewhere between like 2100 or 2250 RPM. It's pretty difficult pin pointing the exact measurements. My temp gun fluctuates at many different temperatures so it's hard to tell which one it actually is....

Other than that I'm still really happy with the side branch resonator! Even though my calculations were not exact it still got rid of 90% of the drone.

If you try this and can get your calculations right the first time then you're good to go.

I also have no mufflers so having it 100% quite inside isnt gonna happen hahaha

johnnxiv · Jun 5, 2015

Re: Getting rid of exhaust drone?

spacemonkee23 said:
It's pretty quiet and low with the setup I have. Practically no raspy sound and zero drone. Because of this thread I now have plans to put in a cable or electric operated cut out for when I want it loud. Prob won't happen for a while but I do have a Welder, exhaust tubing, extra flanges from when I did my old truck exhaust and an old throttle body. I might try and make it work right at the a Y split.
Love the MagnaFlows btw.

If I want 2 magnaflow mufflers, and I also want it to be loud(moderate), What else should I do? resonator delete or Dynomax resonator? or?

phi1542 · Jun 6, 2015

Re: Getting rid of exhaust drone?

johnnxiv said:
If I want 2 magnaflow mufflers, and I also want it to be loud(moderate), What else should I do? resonator delete or Dynomax resonator? or?

I would say resonator. No resonator usually gets raspy. I assume you have stock exhaust right now? If so you gotta change the piping too. I don't recommend using stock piping. 2.25" or 2.5" piping will be good. 2.5" will have a deeper tone than 2.25"

This was my dual magnaflow exhaust. 2.25" piping catback with 12" and 18" Vibrant resonator. I really liked it haha sounded great! Super deep and loud on the outside but not too loud (moderate) but inside the cabin theres little to no drone. It was awesome but I wanted to go louder :lawl: