Dual mode exhaust on a switch

Oct 24, 2016
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Dude! Totally easy. You could always do that BS remote for opening the stock exhaust flap thing and re-purpose it for evil/awesome reasons. (no offense to whoever came up with that stupid thing)
 

doublespaces

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Oct 18, 2016
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lol! Oh come on you know what I meant. And no vodka on a Tues evening. Maybe weds..... :D

Well my idea is to use my wireless relay which operates on the homelink frequency and power the solenoid that switches the vacuum on and off to the stock exhaust flapper. But the stock flapper will be gone and I'll have that line Y'd and connected to both vacuum of the new flappers, welded on to the bypass of my dual mode mufflers. I just haven't finished up the broken aspects of my car before I move on to things like the exhaust, which currently aren't broken.

exhaust.png
 

doublespaces

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Oct 18, 2016
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Don't know if having the Y before the muffler makes a difference…

You know, that is actually a good idea depending on how much space is available. The only problem I see, is if my mufflers can be ran that direction. The internals appear to be designed to be louvered in one direction, I'm not sure how it would sound if you had the exhaust flowing down this angle, which would technically be backwards, probably not very good so this may not be an option for this muffler.

V7fIMTg.png


QTP Screamer is another standalone muffler option, but its too big to fit a pair of them in the space we have.
 
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doublespaces

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Okay, so I'm changing my design. This method allows me to retain a single 3.5" pipe all the way back, and then I have a few different muffler options:

This is the simplest version using a 2 in / 2 out muffler:
upload_2018-8-11_16-28-32.png


Here is an actual version of this:
UTB8O1PewdoSdeJk43Owq6ya4XXaC.jpg


This is another design, it is more complicated but allows the use of two bullet mufflers which opens up more options:
upload_2018-8-11_16-23-20.png


And the third option which is two 1 in / 2 out mufflers welded onto each other, probably the least options available in terms of muffler choice:
upload_2018-8-11_16-24-20.png
 
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fmorelli

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Aug 11, 2017
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The trick for finding a shop - find one that has a mandrel bending tool. I did a quick Google search and you might run down this list. My complete exhaust was built by a shop that has a huge German mandrel bender, and it is a work of art. Was not expensive, either. I'd look at RPM in Chandler, for example.

Filippo
 
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doublespaces

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All the cali people who want to keep their exhaust note but need to keep it quiet for the new laws should consider this.
 

doublespaces

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Got the relay wired up for a test and the homelink button is programmed.

The only issue is the homelink signal is pointed forward so the relay is unreliable even without tucking it back into the trunk panels. If I put my hand behind the mirror it reflects a portion of the signal backwards, I spent a while trying to figure out the problem as I thought there were rolling codes or something strange happening.


I've abandoned the exhaust setup I chose. I think I'm going to put a 3.5" flapper in the tunnel and have the alternate path be muffled with a couple secondary cats inline.

Hopefully I can find enough room in the tunnel to fit all of that. This would let me use a borla xr1 multicore that I wanted to use previously.
 

Kenjermen

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Nov 6, 2016
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I have exhaust cutouts, with remote open. I have the remote programmed to the 1&2 buttons not garage door opener. 1-to open the cutout 2-to close them. I know you aren't trying to get that crazy with cutouts but maybe you could splice in a wireless recover that works for them. My receiver is in the battery tray In the trunk and I have zero issues