Resonators, any input?

[747mopar]

Looking to quite the interior down a bit and have been reading up on resonators seeing how my issues are rpm specific. As of now I have Hooker Super Comps and a 3" exhaust system using an X pipe that dumps out the back, mufflers are the typical oval glass pack (can't remember brand). I love the sound, has a nice rumble but damn does the noise/drone get to you after awhile. Reading up on it it appears resonators might be a good option, never bought one so obviously no clue what to look for. To me it would seem a longer and larger diameter resonator would be more affective? Just looking for some feedback, ideas, suggestions?

 

[drhill]

I added these to mine in the back beside the gas tank.I Lso have 3 in exhaust with x pipe but have magnaflow style mufflers.

 

[Nate S]

They work. Longer is better. NOT the same as glass packs. Could also weld in a J tube. Those work very well.

 

[747mopar]

I added these to mine in the back beside the gas tank.I Lso have 3 in exhaust with x pipe but have magnaflow style mufflers.

View attachment 1028066 View attachment 1028067

Did it make much difference? Seems everything I read suggests putting them as far forward as possible?

They work. Longer is better. NOT the same as glass packs. Could also weld in a J tube. Those work very well.

Another member suggested the J tube... Interesting but will have to get under the car and see how much space I have. Pretty sure I can easily install either one behind the headers.

 

[drhill]

I didn't have room except in the back. It's not bad. I had flow masters on it and the drone that comes from chambered mufflers is insane. After doing some research I found that magnaflow and dynomax are supposed to flow better and have no drone. That did make a big difference in my car and the other resonators that I added was just to take the sound down a little more and it did.

 

[rumblefish360]

Mufflers and sound can be funny sometimes.
In my wife’s ‘67 Cuda, we have the full stem to stern TTI exhaust that has the Dynomax mufflers. I never had such a bad drone with Dynomax before. We were not really to thrilled with that.

Fast forward a year when a head swap was done. Edelbrock’s to Trick Flow heads raised the compression from (IIRC) 10.8-1 to 11.6-1. It got quieter inside and outside. The drone disappeared inside, totally!

The best use of glass packs I have ever made use of has been a glass pack directly connected to the muffler. This puts the glass pack between the header and the muffler.
The glass pack I like the best is from Magnaflow because the inside does NOT neck down in size on the inside at all.

I have experienced that a glass pack or muffler of the same idea works best when used first for drone purposes. For the “under car package it purposes,” a muffler after the muffler style glass pack is largely impossible. I have used a round style glass pack after the muffler next to the gas tank. This has been very effective on sound control for outside the car but not as effective on the inside of the car. But there is a sound & drone reduction. It was just better when the glass pack was first. I think it was largely due to the fact of the thick steel body of the round glass pack before the muffler not letting sound pressure waves through like a thinly wrapped muffler.

David Vizard did some work on exhaust sounds while trying to develop a zero HP loss system. He succeeded. One of the things he did was introduce a sound wave cancellation box or chamber that is installed after the header collector extension with a mathematical size for a given engine size.

This can become a packaging problem under a car due to its limited real estate for fitment. The previously mentioned “J” pipe is an excellent idea. I don’t have any information on the parameters of the pipe size or placement, but videos of this are plentiful on you tube. They are placed all over the place and seem to work since the owner/builder/driver seem very happy with there results.

Once you get there, let us know what you did and how you like it!