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Boss Exhaust Dump Valve Explanation

Does anyone know how the exhaust dump valve works and how it improves performance? I understand how a waste gate works in a turbocharger application and a basic understanding of back pressure as it pertains to exhaust systems and tuning. But I'm not familiar with this concept of an extra side exhaust suitable for an exhaust dump valve. Can someone give a technical explanation of how this works? Or is this more of a gimmick to make the car sound cool like the air intake inlet?
 
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5 DOT 0 said:
more of a gimmick to make the car sound cool like the air intake inlet?

I would say that exhaust note is a BIG component of how enjoyable a car is to drive. I expect removal of the restrictions will make it sound like Ford would have liked it if not for the mandated standards. I do not expect a performance increase. There is actually a quote in one of the mags where Ford says the back pressure goals were met with the GT's exhaust so they focused on the sound quality.
 
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you could also make the argument that the standard dual exhaust is silly as well. Ford could easily design a single that flows as much or more while weighing 50lbs less.
 
Is it correct that Ford is required to meet some federally-mandated noise standard in order to sell the car, but that generally there are no state statutes setting a noise standard? Just trying to see if there is any potential problem with removing the attenuation disks. If there is no problem, then I'm removing them, too!
 
atrain1975 said:
Is it correct that Ford is required to meet some federally-mandated noise standard in order to sell the car, but that generally there are no state statutes setting a noise standard? Just trying to see if there is any potential problem with removing the attenuation disks. If there is no problem, then I'm removing them, too!
I'm not 100% certain, but I'm pretty sure there are local noise ordinances that vary by not only state, but municipality. I think we're going to have to see how loud it is with them removed and then decide if we can "get away with it" or not in our local community. You also have to consider your neighbors, etc. I'm planning on just taking them out, and don't expect it to be ridiculously loud. The car still has cats and mufflers so I'm sure it'll be fine. I also don't think it's going to be that tough to take them in an out without necessarily going to electric dump valves.
 
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Mark said:
you could also make the argument that the standard dual exhaust is silly as well. Ford could easily design a single that flows as much or more while weighing 50lbs less.

Yo mean a single pipe running from engine to tail? Then I have to disagree. Ford could not easily or cheaply run a single pipe that flowed what the duels do. There simply isn't room and building oval pipes cost way more money than round pipes.
 
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908ssp said:
Mark said:
you could also make the argument that the standard dual exhaust is silly as well. Ford could easily design a single that flows as much or more while weighing 50lbs less.

Yo mean a single pipe running from engine to tail? Then I have to disagree. Ford could not easily or cheaply run a single pipe that flowed what the duels do. There simply isn't room and building oval pipes cost way more money than round pipes.

amortizing the tooling and production costs for a single oval exhaust vs. the dual over the life of the model (or several models) would be pennies per vehicle (might even end up costing less at this volume).
 
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Sorry you're mistaken. I worked 30+ years in the auto industry and pennies in the automobile industry don't come easy. What's more the cost of round pipe machines have been amortized for years buying, manufacturing and installing oval pipe machines cost millions.
 

ArizonaBOSS

Because racecar.
Moderator
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Arizona, USA
Some company already made a Y-pipe setup that runs a single exhaust from the cats back, for drag-race weight-savings purposes.

But screw that, it looks weird with only one outlet, plus I love the dual sound.

Municpal law? Local ordinances? Come on, guys. Cops aren't going to care about that unless you live in a retirement community or they are having a bad day. Just remember to be polite when you get pulled over and they'll probably just compliment you on the car and then you're on your way. Just pull the plates :)
 
I'm assuming we will be able to just pull em and forget em but we need someone to get a car so we can find out how loud it is! ;D Unless you have a lift at home, you're not going to want to mess with taking them out and replacing them for track days. So, it's either remove them or put in the dump valves. It's finally above freezing here today and I've got spring fever bad! Two more weeks to my build day!
 

ArizonaBOSS

Because racecar.
Moderator
8,523
2,331
Arizona, USA
I dunno man, if you've already got the car up in the air on jackstands to change wheels & tires for trackdays, the 4 bolts for the plates isn't a big deal.

I'm going to pull mine straightaway and just leave them out, unless they are unbearable for daily use removed.
 
ArizonaGT said:
I dunno man, if you've already got the car up in the air on jackstands to change wheels & tires for trackdays, the 4 bolts for the plates isn't a big deal.
LOL, 10 years ago I'd say the same thing. Crawling under the middle of the car on my back just isn't as much fun as it used to be. After putting my stock rotors back on my GT500 yesterday, I ordered a little roller stool to sit on when swapping pads, fluid etc. :D
 
5 DOT 0 said:
C9 which roller stool did U buy? I've been looking for a Ford one.
A really cheap one. No idea if it's any good but for this price figured I'd try it. For $5 more they have one with flames on the seat lol.

http://www.harborfreight.com/pneumatic-adjustable-roller-seat-46319.html
 

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