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11-30-2014, 09:50 PM | #1 |
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Downpipe Question
Can someone explain how an aftermarket downpipe makes additional horsepower in comparison to a stock unit? I totally understand turbocharging, but don't really understand the role of the DP. Thanks.
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12-01-2014, 01:41 AM | #2 |
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depending on whichever you go will give you different power gains.
Catless being the most power gain vs. catted being less of a gain Downpipes give you more power because they let the exhaust from the motor flow more freely (catless flows more freely than catted hence the power gain). picture a hose with a kink in it being your stock down pipe…. then remove the kink from the hose thats your aftermarket down pipe…… flows better without the kink right? Thats the dummy way of explaining it lol |
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12-01-2014, 06:45 AM | #3 | |
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12-01-2014, 06:56 AM | #4 |
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I've been just reading about the same, so please have a look at this very simple and clear article: http://forums.nasioc.com/forums/showthread.php?t=445812
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12-01-2014, 09:32 AM | #5 | |
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12-01-2014, 10:32 AM | #6 |
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12-02-2014, 01:29 AM | #7 |
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Yes you will still see gains even with an aftermarket catted DP because it still flows better than the stock cat. My hose reference explains it the best. Any free up in the restriction of an exhaust system (especially a turbo motor) will see an increase in horsepower.
Before I got my 550 2 weeks ago I had a 2012 mustang GT. Back when I deleted my cats before adding headers, i gained 20rwhp just from deleting them. |
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12-02-2014, 07:54 PM | #8 |
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Yep I get. So gain is mainly realized with the removal of the cat, or replacement of the OEM cat with a less restrictive one. Basically what I was getting at is there is more to it that just replacing a very short length of exhaust piping. My next question is, are our cars able to pass emissions testing with the catted DP options? I already know they won't pass without cats.
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12-03-2014, 02:03 AM | #9 | |
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You can pass with the catted down pipe, Catless will be more of a hassle, but it can be done. I am going carless on mine |
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