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DIY Turbo Discussion greddy on a 1.8? homebrew kit?

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Old 09-08-2016, 10:22 AM   #21
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It was great actually. Used it for about a year then sold to a friend when I parted and sold the car.

Closed the car was VERY quiet, and it was really easy and simple to open/close it fast.

The only complaint I have about it is when open it sometimes made a little whistle sound at low rpm/load.

It was a lot of fun having people try to pick on a "stock" wrx, only to hear it suddenly get louder, and then they see nothing but taillights

*edit: it's not a coutout though. quite different from one
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Old 09-08-2016, 10:34 AM   #22
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Oh I know. but with a Y-pipe it could be used as one.

My thought process was that these electric ones tend to leak because the stepper motors aren't providing enough force to hold it closed tightly, where as a spring might.

My fear is that they aren't properly machined well enough to not leak some when closed though. Because where yours would be used in line with the muffler, I would be using it pre-muffler in a y-pipe. So, little leaks would kill the whole point of using it.

I'm starting to think this is the only truly leak free solution:

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Old 09-08-2016, 01:58 PM   #23
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Originally Posted by 18psi View Post
This is incredibly cool! I've been looking for a 3" solution like this for my Evo, but couldn't bring myself to buy a Varex muffler seeing as the muffler has an electronic flapper built into it, and it seems damn near impossible to replace it without buying yourself a whole new $400+ muffler.

Plus, I really like that this one is controlled mechanically and can be used on any exhaust.

Last edited by astral; 09-08-2016 at 02:17 PM.
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Old 09-08-2016, 02:01 PM   #24
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see above. results posted
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Old 09-28-2016, 12:40 AM   #25
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Something to look into:

About a year ago I worked with my roommate to fabricate (repurpose) a dual mode exhaust system for his 2015 mustang gt. I got the idea of using the vacuum actuated cut outs from an oem manufacturer. We ended up just pulling mufflers from a Camaro and having them welded in then rigging up some vacuum lines and some other complicated crap in the trunk that didn't end up doing anything.
This was the result.

Another thing I just came up with was using a waste gate actuator to operate the valve. Run a really light spring like (2 psi or something) and when you're in boost the exhaust would be open but under vacuum the exhaust would be closed.
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