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How would you run dual Exhaust?

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Old 08-16-2008, 07:35 PM
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How would you run dual Exhaust?

I know the first thing you guys are going to say is it's not worth the money. Well I can't bring myself, after spending $428 on headers, to choke the exhaust down to one tube only to seperate it out after the muffler so I can have dual tips. Any way I'm wondering whats the best way to run duals? I want to run 2 1/4 inch pipe and I really want both tips to come out under the rear bumper. Any ideas would be great!!!!
Old 08-16-2008, 09:54 PM
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2 cats 2 mufflers, if you dont have to smog, 2 cats and straight pipes
Old 08-16-2008, 10:45 PM
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It's not worth the money.

But, if you're insisting on doing it, make sure you don't go too large on your pipes. The 3.0 needs some backpressure to operate properly. Also, there is no such thing as true duals. A proper exhaust has a X-over pipe midstream to allow one cylinder bank to scavenge from the other.
Old 08-16-2008, 11:01 PM
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Originally Posted by RobD
It's not worth the money.

But, if you're insisting on doing it, make sure you don't go too large on your pipes. The 3.0 needs some backpressure to operate properly. Also, there is no such thing as true duals. A proper exhaust has a X-over pipe midstream to allow one cylinder bank to scavenge from the other.
x2 got to have a little back pressure. the x-pipe helps quite a bit and makes it sound better,
Old 08-17-2008, 07:28 AM
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I wonder how true duals would affect the O2 sensor circuit?
Old 08-17-2008, 07:26 PM
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I like the Idea of an X pipe! I never thought of it I was going to use an H pipe. Would dual 2.25 be enough back pressure?
Old 08-17-2008, 07:50 PM
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considering I've seen 2.25" x-pipes on 5.0 mustangs, and no benefit, other than a louder 'growl' in the exhaust, I'd wonder about the efficacy of 2.25" pipe on a 3.0.
Old 08-17-2008, 07:58 PM
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Remember that with a set of properly designed headers, you time the pulses so they are not on top of each other - this helps a smaller exhaust system handle the flow a lot better.

If you have smog, you're gonna be stuck with one O2 sensor and one cat, so you need to check the laws for your state first.
Old 08-17-2008, 08:03 PM
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Duel exhaust on a 3vze? Thats cute.....

You only need one SINGLE 2.25" pipe. Thats more then enough for this engine. Anything bigger will hurt your performance...but hey. I guess it might look cool.....
Old 08-17-2008, 08:05 PM
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I would think that you'd be fine running a single O2 sensor in one of the two pipes. The O2 sensor measures the amount % of O2 in the exhaust, it doesn't measure exhaust flow or anything else.
Old 08-17-2008, 08:12 PM
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@Matt16-
so you're okay with the ECU sampling 1/2 your engine in order to determine the best fuel ratio for the whole engine...
... the O2 isn't seeing what is happening with the other 1/2...

So, you're okay with running lean in one cylinder and blowing the engine because the O2 is looking the other direction?

Not saying it would happen, but rather 'could'.
Old 08-17-2008, 08:23 PM
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thats why you run an x-pipe with the o2 in the middle
Old 08-17-2008, 08:28 PM
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and doesn't the 3.0 have an O2 in front of the cat, and another behind the cat?
Old 08-17-2008, 08:29 PM
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and if you're willing to siamese the runners for the cat and O2, then why run duals?

answer- there is no benefit in doing it that way.

we're talking about an engine with 3.0 displacement. 2.25 tubing, DOM bent, is more then enough.
V6 duals always sound like rice anyways.

Last edited by abecedarian; 08-17-2008 at 08:32 PM.
Old 08-17-2008, 09:05 PM
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Originally Posted by Strings
I like the Idea of an X pipe! I never thought of it I was going to use an H pipe. Would dual 2.25 be enough back pressure?
x-pipe, h-pipe, w/e, they do basically the same thing just the x-pipe is smoother. good luck finding a good place for it. might have to be off set of the gas tank back by where the old muffler was...maybe?
Old 08-17-2008, 10:45 PM
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Originally Posted by abecedarian
and doesn't the 3.0 have an O2 in front of the cat, and another behind the cat?
Nope. Only the california spec'd trucks have duel o2 sensors.
Old 08-17-2008, 10:55 PM
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Originally Posted by abecedarian
@Matt16-
so you're okay with the ECU sampling 1/2 your engine in order to determine the best fuel ratio for the whole engine...
... the O2 isn't seeing what is happening with the other 1/2...

So, you're okay with running lean in one cylinder and blowing the engine because the O2 is looking the other direction?

Not saying it would happen, but rather 'could'.
I suppose you could place the O2 sensor at the x junction in the duel pipe. I don't think the two banks would ever receive different mixtures, unless something is seriously wrong anyways ie: dead cylinder, clogged injector, failed cold start injector. Basically, I think you'd be fine barring the strangest of circumstances.
Old 08-17-2008, 11:19 PM
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Here's a sketch of what I would do/will do.

Old 08-18-2008, 05:02 AM
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Originally Posted by Strings
I know the first thing you guys are going to say is it's not worth the money. Well I can't bring myself, after spending $428 on headers, to choke the exhaust down to one tube only to seperate it out after the muffler so I can have dual tips. Any way I'm wondering whats the best way to run duals? I want to run 2 1/4 inch pipe and I really want both tips to come out under the rear bumper. Any ideas would be great!!!!



so let me get this straight. You are will to spend, im sorry, waste money to achieve 1/2 hp out of a 3.0.. maybe.



Dude, its not a chevy
Old 08-20-2008, 09:09 PM
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Wow you guys sure can kill a mans dream, but you do raise alot of good points. Maybe I should just leave well enough alone and do a Y-pipe into a Hi-Flow cat and Cherry Bomb extreme (or Super 40 Haven't decided yet). I just thought i might be able to achieve a Deeper more aggressive tone with true duals.


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