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Exhaust? X-pipe or straight through-why?
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03-21-2007, 11:55 AM | #1 |
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Exhaust? X-pipe or straight through-why?
Ok, we now have several manufacturers coming out with exhaust for our cars. Some have a built in x-pipe(crossover) and others are straight through.
Shiv's is straight through and recommends exhaust without the x-pipe to get the full potential. If thats the case, why are these top-notch companies'(Milltek) putting crossovers in theirs. Obviously they do R&D so they must have come up with some idea. If it comes down to sound being muffled then I understand, but if people want performance, they should have options. At least available baffles that you can put in or take out to keep sound down. Thats something Thermal offers on their exhaust for Audis.
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03-21-2007, 12:20 PM | #2 |
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Having a X pipe is in my opinion the most retarded design ever made for an exhaust. What are the really advantages of a design that makes the flow to be altered and disrupted?
Go to your backyard and have to water hoses with water shotting at 100mph collide and see what happens. Water and gases have some flow similarities, the flow of less resistance overrules. Why in the hell would you want a X pipe to disrupt and slow down flow? Not to mention that whenever maintenance needs to be done the weight of both pipings are increased because the cat-backs are united. If someone can please "explain" the benefits of a X pipe maybe I buy beer. my .2c I am with Vishnu on that, straight flow always overrules on turbo cars. Carlos |
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03-21-2007, 12:33 PM | #4 |
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My point exactly. So why is every exhaust being made now pretty much incorporating this backwards design?
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03-21-2007, 01:47 PM | #5 | |
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03-21-2007, 02:01 PM | #6 |
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I cant find pics anymore of the Miltek but I see the Ultimate Racing and CPE exhausts both have it.
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03-21-2007, 02:40 PM | #9 |
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03-21-2007, 02:45 PM | #10 |
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03-21-2007, 02:53 PM | #11 |
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For future reference, you can just go to the "thread tools" pull down at the top and click "subscribe to thread". However, if you knew about that then you were not adding anything to the thread except a count in your favor.
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03-21-2007, 02:59 PM | #13 |
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I think but dont hold me to it but the crossover pipe (x-pipe) may reduce the raspy sound in the exhaust. Since most companies are using straight thru resonated design mufflers the crossover pipe may help balance the air going thru and control the sound a bit.
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03-21-2007, 03:06 PM | #14 | |
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This is a possible explanation concerning your fluid dynamics question. There is laminar and turbulent flow. X-over creates turbulent flow. Believe it or not, turbulent flow moves faster than laminar flow. This has been very well documented for flow kinematics. Thus the possible X-over design. I believe if there are fins arranged inside the tube to create a vortex, such as the spiral grooves in the gun barrel, exhaust may exit faster. |
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03-21-2007, 07:53 PM | #15 |
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I was always under the impression that X-pipes offer substantially better balancing of the exhaust gas pulses. It all comes down to gas velocity. The X-pipe will have better flow.
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03-21-2007, 08:14 PM | #16 |
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Which coming from an exhaust maker brings me to my original question. Why would Shiv say his exhaust is better without it and why would Miltek(I was wrong originally) also not incorporate one? I can only assume that everyone is dynotesting theirs.
Shiv or anyone else(manufacturing exhaust) care to chime in at anytime please.
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03-22-2007, 03:55 AM | #17 |
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http://www.moddedmustangs.com/ford-m...-upgrades.html
This site explains it, read the Mid pipes section. And this http://www.drgas.com/articles/art_syncronicity.php
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Last edited by ac2; 03-22-2007 at 04:18 AM.. |
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03-22-2007, 04:10 AM | #18 |
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This site actually has a better explanation-- I don't know whether or not it applies to the 335i, but the stock exhaust DOES have an x-pipe, if I am correct...
http://www.enjoythedrive.com/content/?id=10185 |
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03-22-2007, 04:33 AM | #20 | |
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03-22-2007, 04:34 AM | #21 |
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03-22-2007, 12:56 PM | #22 |
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