I own a 2012 BMW 328i hard top convertible. I found it a year ago after a long search. Low mileage and excellent condition. I did some minor upgrades on it. New Pirelli tires, ceramic brake pads and cross drilled rotors. I am having a CAI installed next month. I would like a little more sound but it has to be mild not raspy like some of the ricers have. A full exhaust system is pricey. I was wondering if a new muffler could give me a better sound.

 

Ask in the forums at bimmerpost.com. They know everything there is to know about these cars and , like here, they can save you a ton of money and headaches. I've owned a 2008 128ii in Sedona Red for years and I'm about ready to sell it. Sure wish you lived nearby so you could detail the he'll out of it. Good luck with the car.

 

You could have a muffler shop cut off the stock silencers/mufflers and replace with a universal muffler, like a Flowmaster or Borla.

It's a 4 cylinder in the 328 so it's not going to sound like a 6, but shouldn't be bad. I'd check on youtube to see what exhausts sound like, I'm sure there's a few out there.

Edit: Magnaflow looks decent and sounds pretty good $812 isn't bad for a full exhaust - https://www.magnaflow.com/products/1...yABEgIGXfD_BwE

 

Excuse me while I get technical.
and exhaust system is what is called a transmission line.
think of a horn being tuned. the muffler at the end gets matched to the transmission lines impedance.
this does 2 things. 1) it changes the sound and 2) it has a huge effect on the efficiency of the transmission line which in turn changes the engine performance.

Example, you want performance over the full engine band from idle to redline.
The exhaust can be tuned to give you a bump at certain rpms. 3500-4500 for example but at the cost of driveability

 

Ray, it sounds like your goal is a more sporty sound. If so, I would hold off on any changes to the exhaust system until that cold air intake is installed. Depending on the design, that intake will likely result in a much more sporty overall sonic experience with the existing exhaust, or at the very least might impact your decision of just how much louder you want the exhaust to be. Just one opinion based on experience with several of my own sports/sporty car s along with many others that my two sons have owned over the years.

 

I agree Mike, I plan to wait until the CAI is installed. It is a K&N from Turner that advertises an increase in power and sound. Thanks.

 

I have a 6 cylinder in line with twin turbos not a 4.

 

I owned a 2016 228i. Great car.

 

You sure about that? 335 has the turbo 6. BMW switched the 328 to a 4 cylinder turbo for the F30 generation. Same engine that was in my wife’s 430xi convertible.

 

Oops typo error. It’s a 2011 not 2012.