jjcuff1

Well at 50k my car was idling rough. I thougth it was my tune, carbon buildup or miss.

Turns out audi said it was the flex pipe in the exhaust.
I went to my muffler guy and he said it was the dp resonators. They fell apart once he removed. So I went ahead and straight piped the resonators, removed the suitcase resonator and added a non res xpipe.


so just mufflers and cat. It was actually quiet no drone still inside the car but under most loads over 1800rpm the car sound like a tinny gazoo. Just horrible. embarrassing.

so I cut mufflers off and it sound awesome but way to loud and added some magnaflows. that really cut volume down and deepend it up. It sounds awesome now at idle and start up. Upshifts and downshifts backpop and burble under load and you can hear the engine sing as the gears shift sounds like a race car BUT....

Drone in the cabin is horrendous. 1800 is peak but 1700-2400 is very droney. Outside the car people say it sounds like a mean R8 coming.

I ordered 2 12" vibrant resonators 1791 2.25" many people say that will do the trick. My concern is it will help some drone but still maybe too loud in the cabin. I will let you guys know. If it doesnt cut it I will add vibrant ultra quote resonators in addition.

Power wise the car revs a lot faster, probably SOTP torque off idle has a bit loss. but since it is so loud inside I feel the car is slower since I do not lay into as hard like before when it was stealth. I feather it to avoid massive sound and attention.

snagitseven

Just curious (and no disrespect intended) but why didn't you just replace the failed OEM parts at the start? Seems like you are trying resolve the original exhaust system issue with a lot of experimentation and effort. Unless your goal was to get a louder exhaust.

jjcuff1

Good question. I didn't provide the full story.
i complained about the noise to Audi during my service. Plus I was flashed and trying not to dig too much since it was a ecm flash visit too. I got away no td1

tbey have not been good at identifying my nuisance issues.
back up camera blacks out 10% of the time complained for 2 years
passenger door lock on outside won't always open
passenger side view mirrors won't always flip back open.

nuisance stop usually after sitting or raining.

1: anyway they said the exhaust issue was the flex pipes.. I called BS they don't daily often and not at 50k both of them.

2: anything from cat back was no longer under CPO

3: they wanted $1400 to replace the resonators... suck it.

so I wanted a second opinion and a better price and sound for sure. Aftermarket is $1300+ too for catback but I didn't want that. I figure let's try a delete and if too much jus add resonator back.

so new bottle vibrants are here and I think will do the trick for $600 all in. Probably would have been $500 if I didn't go back so many times

DB22

I have read numerous posts regarding exhaust systems, modifications etc. and it appears that the design is a very complex problem to get a system that does not have issues with resonance at a band of certain RPM's. Due to the many factors involved, just swapping out parts to accomplish a task will typically create an unwanted result and could be a significant money sink hole without the proper engineering resources to actually design a new complete system.
An internal combustion engine makes too much noise so somebody designed a muffler to suppress it. The next design made it even quieter and therefore closer accomplished its intention. By some metrics, the quieter the result then the better the task of a muffler is made but then some people decided that they want to hear the engine so then a certain amount of noise was induced by making worse mufflers. If you equate that performance is directly proportional to noise then get out your checkbook but unless it sounds like a Lambo or Ferrari then I'm not convinced that I want to hear it.

williamrossiv

Post a sound clip??? Also, could you clearly list what the entire exhaust setup is.

jjcuff1

Yes I heard the drone thing as well. It is Frequency thing thats all. The V8 have more pules so higher HZ and easier to kill drone and sound better. The 6 and then 4 have less pulses so the resonance for drone occurs at lower hz.

I had stock cats in the DP the middle was completely straight piped and stock mufflers. It sounded fine. NO DRONE in the cabin quiet at idle and start up. BUT under any load outside the car the mufflers were super raspy and farted. sounded so bad.

So I removed the stock mufflers too and added magnaflows. Sounded much deeper and awesome but drone at 1800.

Then added resonators back into the stock position in front of the x pipe. It cut the drone down by half but still there. It changes based on cars temp but pretty loud at cruise inside the car. Outside the car it sounds pretty good. under load it sounds awesome.

The resonators are 12" bottles. They did there job up to 1500 rpm which based on their size makes sense. They dont have enough volume to cut out the drone at higher volume.

So on order is a larger, muffler size, resonated xpipe. I will swap out for the stamped steel one. That is what I originally asked for and what many do and it sounds fine no drone. I am thinking I will be done.

But to be sure I also ordered 2 vibrant ultra quiet larger oval resonators to swap out the bottles. They are an 1" longer and and 2x the diameter.

I should be very silent except at startup and under load, which is perfect.

Under load, now, you hear an awesome bark at bear changes up and down.

jjcuff1

Well the new magnaflow was installed. I cut out the x-pipe and bottle resonaters and swapped the magnaflow in place.

It cutt the overall volume in cabin way down compared to the bottles.
So I am happy with the magnaflow.

It still really grumbles at idle and all around town.
The car is a lot more responsive too then xpipe. Feels less restricted and definitely spools up quicker.

Now for the drone: The below 1500 feels almost stock now at almost all throttle positions.
Drone still builds up though in the cabin but moved. maybe 2k-2.5k range.
With the magnaflow it is much more muted but under any throttle you get the drone


hiway cruising at steady state speed 1800rpm there is mild drone..


It all feels like it is coming from the back mufflers which are 2 straight thru small magnaflows. I still have the new resonators coming too.

I am thinking find a bigger OEM muffler that fits back there. not straight thru to get drone back to 99% stock level and add the resonators in there for some of the idle harness and peak drone at 2k levels.

I think that will get me to a stock or almost stock ride but I bet I will have all the bark I need or could want.

raj99

Post a vid/sound clip of the vehicle and at least we'll know what it sounds like.

BTW, I'm a fan of "tinkering" with the exhaust

CHIO

God Imiss my 4.2 sound