Dual mode exhaust on a switch

doublespaces

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So what I'm looking for is a custom exhaust that will connect to my AD-E ST kit and run all the way back, fully divorced with each side going into a Y pipe splitting off into two pipes. One pipe is straight through, with an electronic cutout. The other pipe goes to a bullet style or any muffler which fits the given space, and then merges back into the straight through pipe and returns to a single exit. Same thing on both sides. Basically this but merging back into a single pipe:

download.jpg
 

Bumbleb

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Very interesting design idea. I thought about going single and then doing a single 3.5 inch to single exit on a 328i bumper.
 
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doublespaces

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Also, I think I'm going to have a 'modular' midpipe area which has vbands so I can attach different things. Some days I may just want a test pipe. Some days, I may want mid cats, or resonators or even an X pipe. With v bands, I could just swap it out and tune my exhaust how I wanted it to sound or smell.
 

doublespaces

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And here is a dual mode E63 powered by homelink... I want pretty much this, but a wastegate or flapper instead of an electric cutout.

 
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doublespaces

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Well, good news, is QTP quoted me 209 per muffler without the cutout. So at least it can be made. The problem, is that they wouldn't have them available this way until after the first of the year, and my turbo kit comes with a single 3.5" downpipe so I'll be stuck...
 

Sered

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You'd be surprised at how quiet a straight-pipe can be with the right diameter on a single turbo. It's not nearly as loud as the stock turbos would be.
 

R.G.

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You'd be surprised at how quiet a straight-pipe can be with the right diameter on a single turbo. It's not nearly as loud as the stock turbos would be.
Crazy! What diameter is that? 1/2" lol


So what I'm looking for is a custom exhaust that will connect to my AD-E ST kit and run all the way back, fully divorced with each side going into a Y pipe splitting off into two pipes. One pipe is straight through, with an electronic cutout. The other pipe goes to a bullet style or any muffler which fits the given space, and then merges back into the straight through pipe and returns to a single exit. Same thing on both sides. Basically this but merging back into a single pipe:

View attachment 316

Exhaust note tuning is such a pain in the ass. Those bullet mufflers won't do shit. I have 2 in each pipe and it's barely quiet enough to not be obnoxious.



Those cut outs look fun. Oh race night, one sec, Beep boop, straight pipes. You kind of have to decide, building exhaust for max performance or best audible note, otherwise you get unsatisfied with both.

The best designed exhaust I've seen on an N54 is Eric's
Whoever drew that up before fab knew what they were doing.
 
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Sered

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Crazy! What diameter is that? 1/2" lol

4" actually. I've got the largest and best flowing exhaust of any N5X that I know of. And it's not even above 50 percentile in the loudness department (except at WOT with the external gates open dump).

It's the single turbo and 1.0A/R exhaust side doing that.
 

doublespaces

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Crazy! What diameter is that? 1/2" lol




Exhaust note tuning is such a pain in the ass. Those bullet mufflers won't do shit. I have 2 in each pipe and it's barely quiet enough to not be obnoxious.



Those cut outs look fun. Oh race night, one sec, Beep boop, straight pipes. You kind of have to decide, building exhaust for max performance or best audible note, otherwise you get unsatisfied with both.

The best designed exhaust I've seen on an N54 is Eric's
Whoever drew that up before fab knew what they were doing.

I am leaning toward exhaust note. I can turn the boost up and am not trying to set records. Got a pic of Eric's exhaust?
 

R.G.

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@Sered you must have 4" exhaust wall pipes too lol. That big of a straight back should resonate something fierce but...variables.


@dubb I don't. The fab design had helmholtz type pipe strategy. #mathishard

@Erichale77 post exhaust fab pics
 

R.G.

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Make sure the fabricator modifies your center H support bar to fit back on. UR racing out of Japan makes an E92 H bar that is a lot beefier if the OEM one doesn't fit. Don't leave that off as you want to add to chassis stiffness when trying to put that much power down.
 
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Erichale77

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Oh i already have a very nice one made that also serves as driveshaft loop. It covers my 4" exhaust too. Ill find a pic of it.