Idea: Group Funded PE Exhaust

[Suhb]

We should get a list of people to pitch into a fund to buy a used 128i PE exhaust for a user to cut it open to see the internals.

There is some sorcery behind the sound of that exhaust. We can't let the secret be kept hidden.

[TheBigChill]

It better be stuffed with $500 worth of ten dollar bills, because that's how overpriced it is. God damn $700 muffler...

You could get a very quick peek at pipe construction (perforated vs. solid, path, etc) using an inexpensive phone-paired borescope. I have one and could lend it (scope, not muffler). Obviously this doesn't cover type and amount of sound deadening material. If I had to guess, I'd say it's a simple straight path of non-perforated pipe in a minimally insulated can.


Edit: Maybe the first image linked to below is helpful.
http://www.e90post.com/forums/showthread.php?t=1263053

[juld0zer]

Xray it?

[kb2wji]

Damn. At first glance I thought this might be a group purchase thread. Once the secret is out, then what?
Option B: Everyone pitch in so I can buy one and not take it apart. Full throttle at redline and you can still hear a mosquito sneeze over the sound of the n52. Ah well, first world problems I guess

[TheBigChill]

I'm willing to bet that the same sound could be accomplished by building a custom axle-back with a small-bodied Borla XR1 or Pro XS muffler. There's nothing magical about the PE, other than its ability to convince people to drop $700 on a muffler.

[ShocknAwe]

It's the same as the stock box, just with a straight through pipe inside instead. And resonator deletion. Could probably have your exhaust modified to sound the same for ~$200 at an exhaust shop.

[Suhb]

I ran with a muffler delete for some time. It is definitely a different sound compared to a PE muffler. It doesn't have the same tone or the exhaust note change above 4.5k. There also has to be some chambers in the muffler that cause the pops and burbles that a muffler delete doesn't have.

[TheBigChill]

The fuel-overrun pops and burbles are more prevalent with the PE for the exact opposite reason; it's lack of baffling, less substantial acoustic fill material, and use of a straight pipe to pass through the muffler instead of a perforated pipe is what amplifies the snap-crackle-pop.

The tone of the PE will certainly be different when compared to a delete, but at the end of the day, those pops and gurgles exist no matter which exhaust you run; it's just a matter of how much can you hear them through the various exhaust restrictions and sound suppression materials.

Keep in mind too that a tune can both increase or decrease the amount of fuel-overrun (and subsequent pops) you get. At the end of the day, it's just unburnt fuel being partially ignited outside the combustion chamber. Ok- I'm rambling now.

[ShocknAwe]

Originally Posted by Suhb

I ran with a muffler delete for some time. It is definitely a different sound compared to a PE muffler. It doesn't have the same tone or the exhaust note change above 4.5k. There also has to be some chambers in the muffler that cause the pops and burbles that a muffler delete doesn't have.

No you don't get it. The stock exhaust is perforated inside. The performance exhaust isn't. THIS IS NOT THE SAME AS A MUFFLER DELETE. The pops and burbles are fuel dumped, and tune related ONLY.

[Zombie_Head]

Surely someone here or on ebay has a cheap used one for sale, since you plan on gutting it anyways.

[minirips2]

Just to let guys know, the BMW Performance Exhaust for 128i is on sale at ECS for $673.00. That'll be $703 shipped to my door. Just ordered it. NOT cutting it open!

[TheBigChill]

I flew to and camped on a Tropical Island in the Caribbean for less than what the PE costs. Perspective

Anyhow, it's even less here: https://www.bmwpartswholesale.com/oe...CABEgKvbPD_BwE