Today is the day I get my S4 back. Michael at Apex Performance and Fabrication (also found on Facebook here) just sent me these pictures last night.... and all I can say is WOW, just amazing work. If you live in the PNW and need exhaust or other fabrication (they do lots of stuff) I certainly recommend this place.  

• Catalytic Converters used: MagnaFlow 53956 (affiliate link)

My initial thoughts of the sound? Yes it has some rasp, but the more I drive the more that seems to go away. So far I think I've put many 100-200 miles on it (video is showing zero miles) since I got the car back and every heat cycle the tone has gotten lower and less raspy. I will say this is much louder then before, I'm a little undecided if I like it or if I need to add some resonators back to it. Likely in a month or so we will have true idea of the sound and a update video to follow. Subscribe to my YouTube channel here.

 - Amazon affiliate links were used in this post

Well my passenger side cat (catalytic converter) cracked right before the flange that connects to the headers. It all happened when I would pulling away kind of hard from a intersection, heard a pop, and the car immediately sounded bad. Drove about 5miles home and captures this video of just how bad it sounds.  My guess is that during our snow storm about a week below that I hit some deep snow and it caused too much flex on the exhaust. Likely formed a crack at that point and just blew when I pushed the car hard. Oh well I knew I would going to need to do something with the cats if I ever wanted to go dual pulley. 

And just for reference this is how it sounded days before when I flashed the latest EPL tune update:

I had the S4 towed over to a Apex Performance & Fabrication. The plan is to take out the old cats, fab a test pipe from the header to the down pipes... and finish with new cats in a newly fabricated down pipe. The owner explained to me there is no point in trying to re-weld the old cats as they will just crack again. And we all know this is a common problem in this platform so that was no surprise. Anyway that is where it is now I will post again with some more videos of the sound changes (if any) once I get the car back. 

Following some of the suggestions found on the following thread, I decided to modify my existing stock exhaust to allow it to sing a better tune. 

https://www.audizine.com/forum/showthread.php/406948-Exhaust-Mod-Resonator-replaced-w-X-Pipe-(video)

So, I had a Magnaflow 11385 installed where the baby resonators are located, and straight piping where the mid muffler.

And here is a drive by, drive away, inside, and some reving all in one:

​As for my initial thoughts, it is near stock like quiet when cruising at 60 mph, no drone at all. Once you open it up it has a prrr like sound very familiar to a VR6 or VW R32 with out the the lower tones. The best part, if you drive it gently, it really is not much louder than stock. Not to mention from the outside, it still looks 100% stock.

If there is anything I am really missing right now is my exhaust from my old B5 S4. I don't think it was the best sounding exhaust, but it was way better than stock. Loud enough to hear the car, but no drone, and did not annoy the neighbors.

This B8 S4 is stupid quiet and it takes the fun out of switching it in manual mode as you can't tell when to shift unless you are watching the RPM's. So... I know the AWE Touring kit is highly recommended, but good lord, $2k is pricey. Should I save up or go custom? Comment and let me know.

If you've seen my car in person there likely one thing you've noticed is my low hanging exhaust piping. Not a subject that I've wanted to talk about as I could have likely gotten it fixed a few years back, but I really did not like the place that I went to. When my wife noticed it a few weeks back I knew it was time to get it fixed.

So I went to a local muffler shop (mufflerkingperformance.com) just down the road and had them fix it. Told them while they were at it to go a head and remove the resonator as my exhaust just seemed too quiet for my likely. I don't want to wake up the neighbors... but I still DO want people to hear me as I'm passing them at full WOT!

Anyway, two hours later and for $120 my exhaust was finally the way it was suppose to be. They replace the piping from the cats to the muffler. Now I just need to clean it up and give it a wash, polish the tips, and likely take some steel wool to get ride of a little rust around the old welds. I'll give it a few months and will do a new videos so you can compare the sound difference.

I'm sorry this took so long to get up. I know a lot of you have been asking for this video and I wanted to make sure it wasn't crap. I also wanted to make sure the exhaust was fully broken in. I do have to say that Audi did a great job keeping engine and exhaust noise out of the cabin because it wasn't until I make this video did I really notice what this exhaust system sounded like. I how you guys in enjoy the video!

Not a lot has happen for 6 months now since my wife and I having our daughter. Family first! I did get a second job so a little money is finally going to the S4. Got my A/C working again since the compressor switch failed. Had to take off the front end to get to it. Thanks again for the help from my buddy Erik at I.P.M. Auto Service. 

Went to Dan Fast Muffler & Brake and got a 3 inch custom cat-back Magnaflow exhaust installed. I did get a resonator install just so it wasn't too loud. So far it is sounding great! I know over time the sound will change so we will wait and see what it sounds like several months later. I do have to say the S4 for sure feel much more torque'e... if that is a word. Most people say they feel more power at the top end with a exhaust but I feeling it more a the bottom end. Maybe it is helping the turbos spool up faster. It was around $550 for parts and labor so I'm happy with the end result!