Following dallas advise/post I thought I gave it a try too. After all, a $350 investment isn't too much of a risk and much to gain. Before the installation I was expecting about a 15hp gain, better throttle reponse and more aggressive bark from the engine and exhaust based on my previous experience with Japanese cars with aftermarket exhaust. Well, not all went as expected.

First, the installation part. After some price negotiation to $350 with custom 2 1/4 inch (1/4 wider than stock) piping right after the cat convertor and two cylinder stainless steel MagnaFlow with chrome tip. The guys at Tony's muffler shop knew what they are doing and was able to get the parts just 1/2 hour after we spoke so I didn't had to tell them what size would fit. In truth, I didn't expect them to install them right away and needed sometime to think about it. However, they had already began to work so I let them. The whole process took about a bit more than an hour and I was able to stick around to tell them exactly how I wanted. The installation was ok and everything was secured and in place. Except for the two pipe not looking exactly alike they did a good job.

I. Sound
The first thing I noticed would of course be the sound. Coming from a Japanese car, I was expecting an aggressive bark especially considering the nice things I have heard about the MagnaFlows. The first sound when I turned the ignition was pretty aggressive and then it just settled down to a non threatening mono tone sound. The pitch is lower than I expected reminding me of the Corvette I recently drove. That's definitely different than a 4 cylinder Japanese car with Borla muffler. I said to myself, "good, not too loud" but then when I stab on the throttle again all I hear is some grainny low tone noise that never never changed which was dissapointing.
Once on the road I was able to get a clear picture of what I would be hearing in everyday driving. In a word, not too happy. There is a low resonance noise like what you would expect from a Mustang that is totally off character of an otherwise quiet Audi, not sure I like it. Surprisingly, that low resonance grainy noise has gone away when rpm goes higher than 2500rpm and the engine sounded very smooth. I guess that's the confort zone. However, I like to keep the rpm around 2000rpm during coasting in everyday traffic and that would be a problem. Don't know if leaving the resonator in would solve that problem. But if you like quiet operations don't even consider this as it would change the entire personality of the car. I can no longer enjoy the music from my Bose system even just cruising in regular speed unless I let go the throttle. There is a bright side, there is a somewhat more aggressive sound to go with the speed. Althought I guarantee you that most passenger would notice something is going on.

2. Power
Don't know if is the sound or it actually gain more power but the car is livelier all of the sudden, anything after 2500rpm the engine becomes more responsive; guessing the turbos was able to spool up quicker and suddenly the car feels lighter. Under the 2000rpm seemed it lost some power, and maybe it's because the constant resonance making it seem like the engine is working harder than it is. I think once the turbo started to work the noise from the exhaust is being absorbed and sound very subdued; exactly the opposite of one would expect, when rpm climbs the noise actually smooths out and became quieter sadly that tone stayed constant to the redline which is a bit of dissapointment. But like dallas said, at least now I can shift by ears and also made me appreciate the quietness I had before. Well, can't have everything.....

Advise to all, maybe it's my personal preference, but I think you should leave the resonators in place and avoid that dreaded resonance during that 1750 to 2500 rpm that I used so much during everyday driving. Power is defintely increased and so was the throttle response and turbo spool up. But would I have done this again? probably would put the originals back in a few month. Personally, I like all that power without any sign that the engine is working and so does my passengers; I can floor the throttle and feel that push to my back and have the passengers thinking I barely tabbed the throttle. Now it became obvious that I am driving hard.

 

Thinking of getting the pipes made up as you did; but, keeping the resonators in place and hold the pipes for a trip to the track (if I can ever get away for work long enough). Or, leave the pipes in if I like the sound. Worth a try.

 

but a slightly different model. Originally installed just the muffs. It was just too loud for a passenger car. Very aggressive note when accelerating, really liked that. But the drone at low rpm's cruising was unbearable. Went back to muffler shop and had them add two 12in resonators. Really quieted the whole car down. Still has a slightly more aggressive sound than stock. The drone was diminished but still there. I find myself keeping the rpm's up just to avoid the drone. Passengers still find the drone unpleasant. If I had it to do again I would save up and get the Miltek. However I just can't spend anymore money on the exhaust, I will just live with it I love it when I accelerate but hate the drone when cruising. Need to save my money for KO4's

 

LOL : )))

 

<ul><li><a href="https://forums.audiworld.com/a6/msgs/239520.phtml">MagnaFlow Issues</a></li></ul>

 

I think I went too far with 1/4 inch wider piping right after the cat. I personally think the drone from low rpm is due to lack of resonators. If you are very tempted to do something and don't want it too loud you might wanna try keeping the resonator and choose a muffler that is of higher pitch sound freqency(never really like the Mustang sound on European cars anyways) and maybe you won't have the same problem I have.
I have to say 2.7dallas is way too generous when he say is barely noticeable. The drone is always there and funny thing is that it actually smooth out and get quieter as rpm climbs.
If you take the piping after the resonators, you'll find there are two bumps that goes inward reducing the overall diameter of the piping. So I think that should go. Changing to wider piping and before the resonator and keeping the resonator wouldn't make much sense since the diameter of the resonator is still just 2 inches.
Doing all this just make me more appreciative of the factory unit; a quiet assasain that inpresses the passengers without making them aware that we are trying.

 

Any better mufflers??? Should I keep the resonator on?

 

Yes! Audi probably spent a few bucks on the RS6.Soon,there w/b a vastly superior aftmkt design?

 

i took my resonators out...there was a slight tonal difference, but not that big of a change. I noticed the throttle seemed a little more responsive as well...

i just cant wait to get my car back with the 3" downpipes! you will have full report + videos mid next week...and more to come when I have full 3" exhaust system up and ready!

 

I doubt you lost any power at all anywhere in the powerband, but the curve may have moved slightly. I wish people lived near Pittsburgh, then I could log some before and after with/without the resonator to see if there is even a performance gain to begin with.

-st