Stop the Drone - Helmholtz Style

[BigRed585Lbs]

Everybody seems to be concerned with this subject. A solution is here.

[hoffmk2003]

I think you guys need to grow a pair and stop letting your wives complain so much. I have a LM1 and it is loud and I like it. If you want quiet go buy a magnaflow exhaust or leave the stock exhaust on there.

[Dr Jkel]

Noob here who doesn't understand much of the technical aspects of this, but I just put on a Borla ATAK Axle back and the drone is terrible when cruising. Will this work for my situation. I have headers and HF cats. Thanks

[BigRed585Lbs]

It will work on any exhaust set-up with a drone problem. All you have to do is find what particular frequency is causing the problem and add the j-pipes of the proper length. Drone gone. Mama happy.

[Dr Jkel]

Originally Posted by BigRed585Lbs

It will work on any exhaust set-up with a drone problem. All you have to do is find what particular frequency is causing the problem and add the j-pipes of the proper length. Drone gone. Mama happy.

Ok I'll bite, How do you find this info out and how do you know what length.? I appreciate the help.

[BigRed585Lbs]

If you'll go back to the beginning of the thread and read it all the way through (yes, all the way), we've covered everything you'll need to know. No sense in going over it all again.

[BigRed585Lbs]

Well, I went back and looked for all the "theory", and left the negativism and BS behind.

You can learn a lot by reading post numbers 1, 28, 40, 45, 51, 53, 97, and 98.
Post # 56 is a link to an iphone app that will help you find that drone frequency.

Just trying to make the Camaro sing a sweeter song. (Sick of hearing those Ford guys!)

[Roger Ramjet]

Here is the math done for you.

[Roger Ramjet]

I still would like to try tuning out the drone. See this:

http://www.camaro5.com/forums/showthread.php?t=104546

Anyone around Washington DC with A6 drone that would like to test this?

[Roger Ramjet]

Anyone try adding the pipes?

[GrinderSS]

Originally Posted by Roger Ramjet

Anyone try adding the pipes?

I'm about to try it on my car. I have the JBA 3" competition exhaust system with LT headers. The sound is fantastic, but it drones like crazy. The problem it that I'm not sure I have room to install the Hemoltz tubes.

My peak drone is at about 1900 rpm, but the drone exists from 1700 through 2000. I'm hoping the Hemoltz tubes have a similar effective range.

[Roger Ramjet]

I sized my J-pipes for 1800 RPM but they get quiet around 1500 RPM.

[zepcom]

Originally Posted by Roger Ramjet

I sized my J-pipes for 1800 RPM but they get quiet around 1500 RPM.

You may have forgotten to accomidate for stainless steel "Growing" when heating up. Thus, your calculations may be off just a bit.

Did you make your J's adjustable? Perhaps 1" longer would do the trick...

[ssmike]

Originally Posted by ZAPSSRS

Is there room for a J pipe if you have rear mufflers such as on the Kooks Full system which I am told is similar to the Corsa Mufflers.

SSMIKE - Did Solo decide against the J pipe since you did not have the issue cruising?
When I am on the Intersate, I cannot let the RPM drop below 2k regardless of the gear I am in. I have found that I can never use 6th gear and have to drop down to 4th when cruising at around 55 or so.

I ran with this exhaust without a cam and tune and it was not as bad.
Love the Idle and WOT, but cruising is not good.

Yea, My drone only gets loud when going uphill loading the engine, otherwise it's quite tolerable with really NO drone when cruising steady! The resonators helped a little by virtue of lowering overall volume of the sound. They actually gave it a bassier idle and took away the loud harshness. I'm very pleased with the sound now and drone really issn't an issue!