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shutting up a bridgeport exhaust

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Old 10-17-08, 02:23 AM
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shutting up a bridgeport exhaust

The car is a half bridge with a aspec 500r turbo. I have been running it through my 4" exhaust and well... its way to freaking loud. Here is my idea to shut things up at cruise and for normalish driving. On the main exhaust line there would be an electric cut out blocking the flow completely. There would be a bypass around the valve using 2 or 2.5" piping. That flow would pass through a muffler then dump back in behind the valve. A boost pressure switch would be run to a relay that would have the power such that it make sure the valve would be in the closed position at under X pound of boost and it would open above that. A diagram is bellow.




A few questions.
1. If i keep the power on the relay, have the power set to close the valve when the valve is already closed, will this destroy the motor in the electric cutout. I emailed a company that makes cutouts i have yet to hear back from them.
2. will 2.5" piping be ok for the car at idle to say 6psi of boost?
3. If the electric cutout can not work for this, i would like to use a wastegate actuator to open/close the valve. How much travel do those actuators have? If i go this route, i will probably use a 6psi wastegate actuator, i can use a boost controller to raise the pressure at which it opens.

Any input on this idea would be great. If this is a bad idea please post alternatives
Old 10-17-08, 02:59 AM
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oo, just found something:

They provide these specs:
Controls up to 2 QTECs
Calibrates each motor independently and synchronizes their position
Automatic close at power up
Digital status displays shows butterfly position
Manual pushbutton operation for open, close or partial open
User configurable partial open position
2 Memory preset partial open settings
Short circuit protection on motor drive electronics
Fault detection and reporting
Automatic open or close by grounding or not grounding the trigger wire (for use with Engine Management systems)
LED butterfly position status
0-100 0=Closed and 100=Wide Open

190 for the cutout, 126 for the controller. so 316 for the part+shipping

anything cheaper?
Old 10-17-08, 09:04 AM
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Originally Posted by wackaloo13
oo, just found something:

They provide these specs:
Controls up to 2 QTECs
Calibrates each motor independently and synchronizes their position
Automatic close at power up
Digital status displays shows butterfly position
Manual pushbutton operation for open, close or partial open
User configurable partial open position
2 Memory preset partial open settings
Short circuit protection on motor drive electronics
Fault detection and reporting
Automatic open or close by grounding or not grounding the trigger wire (for use with Engine Management systems)
LED butterfly position status
0-100 0=Closed and 100=Wide Open

190 for the cutout, 126 for the controller. so 316 for the part+shipping

anything cheaper?
This one is way cheaper:

http://www.atpturbo.com/Merchant2/me...egory_Code=BCS

Its a nice piece from a reputable company and you can get it with the actuator if your choice in 2 psi increments if I am not mistaken....not to mention it will be way less complicated.....less chance of failure.

It can be purchased without the "Tee" for about 220.00.

Chris
Old 10-17-08, 08:51 PM
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thats only a 3" opening
Old 10-17-08, 09:08 PM
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Originally Posted by wackaloo13
thats only a 3" opening
Wack,

it is only a 3" opening but this essentially makes your full 4" exhaust system obsolete.

This basically turns your downpipe into a large dump tube under boost and then when your "cruising" it shuts..

So in reality, you could run a normal exhaust with a high flow cat / resonator and then have this in and it will flow better than a 4" inch exhaust

I might have to look into this.... I wonder how difficult it is to tune a car with this mod
Old 10-18-08, 03:24 AM
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I thought about the atp turbo dump. I do not want to run an open down pipe. I would like to keep the exhaust i have but keep it a bit quieter when im cruising. Apex'i makes a mechanical valve that goes inline with your exhaust. To quiet thigns down at cruies you just close the valve a bit. They offer an electric controller but it is 500$. I checked out a couple of these cutout companies, the main problem is that the valves take 3 to 4 seconds to open. This is way to slow.
Old 10-18-08, 10:14 AM
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Engine, Not Motor

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How about a resonator?

Straight through stainless packed resonators are cheap. Mine easily eliminated 75% of exhaust noise.
Old 10-18-08, 10:47 AM
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Or just find/make a butt plug for the tip. Just can't rag on the car with it installed so you need to use your head as far as that goes - but it will cut the noise *WAY* down for cruising
Old 10-18-08, 02:23 PM
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Originally Posted by Aaron Cake
How about a resonator?

Straight through stainless packed resonators are cheap. Mine easily eliminated 75% of exhaust noise.
I have a magnaflow 4" muffler in the middle as a presilencer
Old 10-18-08, 04:46 PM
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i also have a 4" magnaflow and it didn't really make it that much quieter. i thought it would be more noticeable.
Old 10-18-08, 05:26 PM
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if you already have a resonator and the car is too loud for you, you simply made a bad decision to bridgeport your car. And the 4 inch exhaust isn't helping. That's the bottom line. It's a modded car, not some kind of Veyron or other such car that is both quiet and powerful/responsive from the factory.

People expect too much from hopped-up 20 year old cars...
Old 10-19-08, 10:32 AM
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Sounds like the Magnaflow part might suck then.

I have a 3" Vibrant "ultra quiet" resonator, and two straight through mufflers at the back. At cruising speed it's far more quiet then most of the ricer Hondas with fart cans.
Old 10-19-08, 06:12 PM
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Originally Posted by Aaron Cake
Sounds like the Magnaflow part might suck then.

I have a 3" Vibrant "ultra quiet" resonator, and two straight through mufflers at the back. At cruising speed it's far more quiet then most of the ricer Hondas with fart cans.
I might have to try this.

Also, there is no reason why at cruise that the car can not be quiet even if the car has a half bridge.
Old 10-20-08, 09:26 AM
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Exactly. I cruise around 2000 - 2500 RPM most of the time and the exhaust is disturbingly quiet. With the windows up it's like driving a Civic.
Old 10-21-08, 05:42 AM
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what`s wrong with too loud ,i get myself a pair of 15cent ear plugs for long jouney`s, every one else just has to put up with it !
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