Help with S54 swap exhaust issue

I did the S54 swap in my sedan and I'm trying to figure out the best solution to making a exhaust system work with my M3 rear bumper. As most of you know M3's do not have a spare tire wheel well where as non M's do. Right now I have pipes running around the spare tire well but no muffler at all so it's annoyingly loud.

The spare tire well is in the way so I cant put a OEM or aftermarket M3 muffler on. I found this picture of one idea but do you guys think that 90 degree angle curve of the piping will restrict air flow making the car loose performance? I don't really want to cut out the wheel well and risk weakening the frame structure of the car. I'm open to any advice/suggestions.

What parts and pipes make up the exhaust system on the rest of the car? Oem s54 cats,non m resonator or x pipe? Or is it all M exhaust and you are just having trouble with the muffler?
You can replace the X style resonator with a muffler,put two individual resonator between the headers and the new muffler,and then use the photo you posted to fab that style tail pipe.

sent from my ATARI sc1224

Originally Posted by HiHoBrian

What parts and pipes make up the exhaust system on the rest of the car? Oem s54 cats,non m resonator or x pipe? Or is it all M exhaust and you are just having trouble with the muffler?
You can replace the X style resonator with a muffler,put two individual resonator between the headers and the new muffler,and then use the photo you posted to fab that style tail pipe.

sent from my ATARI sc1224

It's all M but i have no room to put a M3 muffler so it's extremely loud. What kind of muffler do you guys recommend? I know it's going to be louder than a non M no matter what I do but my main goal is to minimize the cabin drone as much as possible.

Here is what my setup looks like right now.

http://imageshack.us/g/1/9762420/

To be honest with you, I don't think you'll have a choice on this one. As you already know, you wouldn't be able to fit an OEM M3 muffler because the spare tire wheel well is in the way and all aftermarket M3 mufflers are built around the OEM m3 exhaust/fitment so even if you went with an aftermarket one, it still wouldn't fit unless you cut out the spare wheel well. The only thing you could do is fill the mid sections with resonators but even THEN it still might be too loud for your liking. As per you losing performance with the 90 degree angle statement, essentially you SHOULD lose a bit of performance because the airflow is changing path at such an extreme angle instead of free flowing all the way out the back of the car. Would it be noticeable? I have no idea, more than likely not though. Hope I helped a little bit.

Ya. I dont like the looks of that 90degree .basically defeating the whole purpose of your exhaust unless it was a 3 inch pipe at bend or something. I still cant see why you cant use a stock muffler mount? How are pipes run differently right before spare well?

update:

So I purchased 2 Magnaflow 10416 mufflers to put on both sides of my spare tire well. After thinking things over and talking to the exhaust shop I figured this will not give me the results i'm looking for. Still would be overly loud and annoying because these mufflers aren't really true mufflers...more like bigger resonators.

So I ordered this catback system from Umnitza:

http://www.umnitza.com/e46-3series-q...ust-p-190.html

This was made for non M E46's with M3 rear bumper but should work with my car.

Did it work? Did you have to widen the rear fender to get the bumper to fit?

how about chopping the spare tire compartment so you can fit a complete M3 muffler system like the Rogue? I don't think it would significantly weaken the unibody structure as long as you welded in a plate to take up that space...

Did the Umnitza work?

OR you could run a stock style exhaust.

Originally Posted by wshgrntd

Did the Umnitza work?

Yeah umnitza exhaust bolted right up and works great.