September 7, 2023
What's being installed: Active Autowerke Single Midpipe
There is no surprise that the S55 isn't the greatest sounding M car to ever come out of BMW. I'll be honest, I was a bit underwhelmed at the exhaust note when I first heard if way back in 2015. Especially coming after the glorious V8 S65, it was a hard pill to swallow. However, I had a lot of experience with the S54 in my e46 M3 so I knew the S55 could sound good. I just needed to find the right solution.
Naturally, I started my search looking at full catbacks, but my findings were that no one was taking care of the tone. It was more about just getting more volume and whatever sound came out, that was it. With that being said, I had the AA midpipe in the back of my head, but couldn't understand how JUST a midpipe would make that car sound that much better. Luckily, a good friend of mine has an f80 with the single AA midpipe so I swung over to his place to check it out. Started the car up and I was blown away at how much better (and louder!) the car sounded. It sounded deep, throaty, and way more aggressive than the stock exhaust. I was sold right then and there. I did briefly look at the EL midpipe by AA, but have heard that it is a much higher pitched note, which is not what I am after.
Placed an order for the AA single (non res) midpipe and waited for it to arrive. Now, I won't lie, I had this sitting for a few months before I got around to the install. Mainly due to limited free time, but also a part of me was a bit anxious to cut up my OEM exhaust on my new (to me) M3. What if I screw up? What if I cut it wrong? Lots of intrusive thoughts ran through my mind, but I decided to suck it up and just get it done.
Marked up my exhaust to the 1.5" from the back weld per AA instructions and I got to cutting. Wasn't sure how the saw would react laying under the car in a bit of an awkward position (I NEED A LIFT!). BUT! it got the job done. Nice even cuts and everything went through like butter. Now that the "hard" part of the install was complete, I felt a sign of relief knowing it was going to go smoothly. Got the remaining bolts off the exhaust off and removed the stock midpipe from the car.
Comparing side by side, you can instantly tell why the OEM exhaust was so quiet and so restrictive. Much smaller diameter piping and resonators galore. I knew this was going to be the right step in the right direction. Crawled under the car once again and got the midpipe situated in position and bolted down. I was reassured I cut properly once I held the midpipe into place and saw it line right up with the OEM muffler. Bolted all the hardware and clamps down and it was ready for its first start.
Since I have the BMS valve controller, I made sure the valves were open and got the car started up. My ears were smiling hearing the gigantic roar from the car and immediately thought.... NOW It sounds like an M car. Checked for any leaks (there were none) and I set off for my maiden voyage.
To my surprise, it was still fairly quiet in the cabin. Definitely more audible, but I understood why many F8x owners install this midpipe and be done with the exhaust. It's a perfect OEM+ setup. When you romp on the car, lots more gurgles and pops are audible. Car just sounds more free and open, but close the valves and the car sounds like a comfortable, quiet cruiser.
Very very pleased with the outcome of the AA midpipe as it gave me validation that this car CAN sounds good. But, if you know me... I always want a bit more. More to come on that...
https://www.youtube.com/watch?v=N2m5vpNO1Lg