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Old 11-18-2012, 09:15 PM   #61
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Why not a throttle body with a wastegate can on it?

Dann
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Old 11-18-2012, 10:24 PM   #62
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You can buy switching ones called "varex". That comes with a little central locking-like remote where you can switch between quiet and loud. They're a bit expensive if I recall correctly, but they are good to go out of the box and AFAIK dont suffer from rattling.
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Old 11-18-2012, 10:41 PM   #63
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Quote:
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Why not a throttle body with a wastegate can on it?

Dann
I love how this repeats every time this thread is dug up from the dead and people still dont get it. From memory there were 2 other threads on this same thing at the same time as this one.
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Old 11-19-2012, 03:01 AM   #64
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Quote:
Originally Posted by Vilko View Post
You can buy switching ones called "varex".
Just looked these up, hopefully not a repost. They appear to be a nicely executed dual-stage muffler with electronic
remote control from Ozzieland. Varex offers 3" & 3.5" inlet/outlet oval mufflers (pn# MK11-300 [3"] and MK11-350
[3.5"] are both $500 shipped) That price includes the adjustable electronic hardware & wiring. I'm curious as to the
diameter of the butterfly valve, and the durability of the actuator mechanism/motor.




Attached Thumbnails
My 3" custom exhaust with spring loaded flapper valve-vmk11-300.jpg   My 3" custom exhaust with spring loaded flapper valve-dsc01086f.244174746_std.jpg   My 3" custom exhaust with spring loaded flapper valve-varex-muffler.jpg   My 3" custom exhaust with spring loaded flapper valve-62355d1239235277-xforce-varex-muffler-remote-control-varex2pp9.png  
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Old 11-19-2012, 03:37 AM   #65
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yeah I have one of those in the shed right now.

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Old 11-19-2012, 03:44 AM   #66
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Quote:
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yeah I have one of those in the shed right now.

Dann
Pictarz! What model/size? Any idea on butterfly plate diameter? Is it well-constructed?
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Old 11-19-2012, 07:30 AM   #67
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Hang on, You want me to just get it out and review it? These are pretty common down under.

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Old 11-19-2012, 09:11 AM   #68
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Too bad we don't have em here. $500 is definitely not the kinda price I'd want to be a guinea pig for, and I'm not sure these will hold up long term.
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Old 11-29-2012, 07:29 PM   #69
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That looks like someone has chromed a power window mechanism (the flatted sides of the motor look familiar) and connected it to a throttle plate. The main concerns would be motor heat and the type of bushings used for the throttle. It would have the same problems as electric cutouts. You could use an electric cutout with a resonator ahead of it or one with a resonator after it in a dual exhaust setup to get the same effect and the heat buildup will not be nearly as great. Slight leakage would be no more of a problem than with the integrated muffler/flapper setup and parts would be replaceable separately.
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Old 09-15-2015, 01:14 PM   #70
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I'm desparately looking for one of these for my subaru.
found this:
3" Exhaust Assembly with Spring Loaded Flapper Valve | eBay

not sure what kinda spring tension his has, doesn't say.

Jason/Tim,
Any more input on these now that it's been quite some time?
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Old 09-15-2015, 01:29 PM   #71
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That's a great price...buy one and let us know how it works out.
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Old 09-15-2015, 01:38 PM   #72
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Why the hell would they make the outlet 3.25"?

Either way, you could absolutely make it work. And since the spring is external, you could easily swap springs around or maybe make a safety wire travel limiter.
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Old 09-15-2015, 01:45 PM   #73
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Quote:
Originally Posted by 18psi View Post
I'm desparately looking for one of these for my subaru.
found this:
3" Exhaust Assembly with Spring Loaded Flapper Valve | eBay

not sure what kinda spring tension his has, doesn't say.

Jason/Tim,
Any more input on these now that it's been quite some time?
From memory the above looks like a dead ringer for the one I excised out of a Dynomax VT muffler and put behind my big Magnaflow.

It's still working well. When I'm backing up with a particular combo of gas and clutch it'll sometimes rattle with a ringy tone to it, but other than that it's pretty unobtrusive. And quiet at cruise.
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Old 09-15-2015, 01:47 PM   #74
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Awesome. I'll order tonight
THanks
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Old 09-15-2015, 02:07 PM   #75
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Yeah looks exactly like the dynomax unit.

What are you trying to fix? Why all of a sudden?
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Old 09-15-2015, 02:18 PM   #76
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see other thread

it's not sudden, but it became a problem after going to a turbo with a much larger hotside, and catless really hi-flow downpipe, and equal length header.

And the "problem" is only at low rpm, which is really weird. it's a pulse more than just noise. you can feel the pressure, if that makes sense
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Old 09-16-2015, 12:37 AM   #77
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Ya the low speed bassy thrum was noticeably reduced by the flapper.
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Old 09-21-2015, 01:06 PM   #78
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Attached Thumbnails
My 3" custom exhaust with spring loaded flapper valve-80-exhaust_ecv_957c0ab8803ae3563397be01aee7fe00d6d9aec3.jpg  
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Old 09-22-2015, 10:31 AM   #79
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^

I like it. Some people have added surplus power window motors (that cost under $30) to a flapper valve and have an electric exhaust valve. No adjustment necessary.
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Old 09-22-2015, 01:00 PM   #80
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My concern with any type of electric motors is that they all tend to die fast.
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