Dual mode exhaust on a switch

doublespaces

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Oct 18, 2016
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So I drew this tonight, basically its the iPE exhaust but with waste gates and measurements given a single 3.5" exhaust. Spintech makes a SuperPro Street 9000 4x6x9 muffler with the option for an offset 3" or 2.5" inlet and dual outlets:

http://www.spintechmufflers.com/muf...-prostreet-muffler-9000-series/prod_1018.html

exhaust.jpg


pyRScZl.png
 

doublespaces

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Ha! The wastegate on muffler is a great idea. Love it. What # spring would you run?

Not sure, with a 60mm wg I'm not sure what spring options if have. It would be dictated by how much vacuum gets sent back to the stock muffler. I'm going to switch that solenoid manually using my home link and a receiver that operates on the old home link frequency. Hopefully I don't have the find a custom spring?
 

R.G.

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Not sure, with a 60mm wg I'm not sure what spring options if have. It would be dictated by how much vacuum gets sent back to the stock muffler. I'm going to switch that solenoid manually using my home link and a receiver that operates on the old home link frequency. Hopefully I don't have the find a custom spring?


Sounds complicated. I'd just have it boost referenced by testing whatever spring it comes with then adjust from there.
 

doublespaces

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Sounds complicated. I'd just have it boost referenced by testing whatever spring it comes with then adjust from there.

I wanted to retain the switchability otherwise I would do it that way. Besides there is already a vacuum source back there.
 

R.G.

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Yea, I get that. I'd make it bit more stealth then reaching for my mirror. For example, my linelock is just below headlight switch but cool that hardware already there for wireless operation!
 

doublespaces

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Yea, I get that. I'd make it bit more stealth then reaching for my mirror. For example, my linelock is just below headlight switch but cool that hardware already there for wireless operation!

My tints are decent, nobody will see me activate it. And even if they do, it will probably be as I am pulling out of my neighborhood.
 

doublespaces

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I contacted spintech. They said they could do something with a 9x9 muffler which does what I want, but it wouldn't be quiet at all. I gave them some expanded dimensions at 9x14, hopefully that not only fits but could help make the restricted outlet more...quiet.

exhaust.jpg
 

b1mmr

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I'm very interested in this and getting tired of my muffler delete.. I've always wanted to use the wastegate from the stock exhaust for something.:D
 

doublespaces

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I'm very interested in this and getting tired of my muffler delete.. I've always wanted to use the wastegate from the stock exhaust for something.:D
Well the stock exhaust has some kind of vacuum flapper in it. This probably won't be using a vacuum flapper as they are prone to leaking and sometimes don't sound good. This will be using a wastegate which is more expensive but I think it would turn out better.

The car comes with a constant vacuum source from the engine all the way back to the tail where there is a solenoid which flips this vacuum source on and off, which controls the flapper. This solenoid is controlled by a pin on the DME I am assuming, and connects to the solenoid through some kind of connector. I intend to find out what the part number is for the connector so I can wire up a very small wireless receiver box I bought. This box has a fob, which runs on the same frequency as the homelink, so hopefully that works to toggle it on and off. The vacuum source itself, would need a Y splitter to go to both wastegates.
 

b1mmr

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Sounds like a very good plan, I hope you can make it work in the end! Love when people do stuff differently.
 

doublespaces

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So the design I had would be a little too difficult to get right. Trying to find or design a muffler that did a decent job of silencing while fitting the available space is next to impossible without splitting before the differential. Not to mention my car has an extra brace in the rear behind the differential, so I decided to split back into two pipes before the diff and use two different mufflers which already serve the dual mode purpose.

335Exhaust.jpg


I bought two 60mm wastegates and two flowtech warlocks, which are basically qtp screamers without the valves(or high price):
387warcut (1).gif
 

doublespaces

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Oooh! Those are cool. You're an animal.
I still need to tear into my left trunk panel to access this solenoid and see if I can trigger it on and off. I have some parts coming in tomorrow, perhaps I'll get the wrenching bug and go out there to check it out. I also need to hook up this flapper to the vacuum back there, make sure it can open two of these valves simultaneously.