Open Downpipe

Headers, cats, uppipes, downpipes, midpipes and mufflers.

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92legacyss
First Gear
Posts: 99
Joined: Thu May 07, 2009 2:39 am

Open Downpipe

Post by 92legacyss »

What are everyones thoughts on running an open Downpipe. other then loss of back pressure are there any problems with doing it?
92 ss 5MT..TD04, 02' Wrx TMIC, XS power Atmos. BOV and Gripforce stage 2 w/ WRX OEM Flywheel, Equal length headder and catless uppipe. Open DP and soon tobe CBE, WRX struts and springs, MBC
gijonas
Fourth Gear
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Joined: Sat Nov 08, 2008 10:57 pm
Location: Damariscotta, Maine

Re: Open Downpipe

Post by gijonas »

Noise,exhaust fumes,legality,catching shit on fire,lack of benefit.Other than that its a sweet idea.
94SS.Wiseco forged pistons,TD04,TMIC,WALBRO 225,440's,3" all the way,revtronix stage 2,enough other crap to fill the internet.

THE TRIBUTE BUILD>>>LINKY LINK>>> http://bbs.legacycentral.org/viewtopic.php?p=295455#295455
93forestpearl
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Location: Twin Cities, MN

Re: Open Downpipe

Post by 93forestpearl »

92legacyss wrote:What are everyones thoughts on running an open Downpipe. other then loss of back pressure are there any problems with doing it?


Uuuuhhhhggg. The mere mention of the word "backpressure" makes me want to punch babies.





On a turbo car, the faster you can expel energy after the turbo the better. 4in downpipe? Hell yes. No downpipe? Even better. Whatever you can put up with is best.


On N/A cars, maintaining exhaust velocity is what is important. Somehow, the term "backpressure" came in and totally skewed what actually counts in an exhaust system.
→Dan

piddster34 at h0tma1l d0t c0m
92legacyss
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Posts: 99
Joined: Thu May 07, 2009 2:39 am

Re: Open Downpipe

Post by 92legacyss »

Well i'm not 100% on doing it yet but i think i will give it a try at least untill i have to get an inspection. i just need the flow i have header and 2" catless uppipe on the car already but i have heard that your exhaust is only as strong as its weakest point sooo open downpipe sounds good right about now. i will keep you all updated
92 ss 5MT..TD04, 02' Wrx TMIC, XS power Atmos. BOV and Gripforce stage 2 w/ WRX OEM Flywheel, Equal length headder and catless uppipe. Open DP and soon tobe CBE, WRX struts and springs, MBC
sqc151
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Re: Open Downpipe

Post by sqc151 »

are u running an o2 sensor or no?
92legacyss
First Gear
Posts: 99
Joined: Thu May 07, 2009 2:39 am

Re: Open Downpipe

Post by 92legacyss »

Just factory o2 no wideband yet
92 ss 5MT..TD04, 02' Wrx TMIC, XS power Atmos. BOV and Gripforce stage 2 w/ WRX OEM Flywheel, Equal length headder and catless uppipe. Open DP and soon tobe CBE, WRX struts and springs, MBC
Mattheww044
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Joined: Tue Nov 28, 2006 8:17 am
Location: Spokane, WA

Re: Open Downpipe

Post by Mattheww044 »

I ran the DP with the midpipe for a few days, and it sounded soooo freakin awesome. But rediculously loud. I would keep it like that if I could, but not worth getting tickets and all the attention it brings
Redlined
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Joined: Tue Apr 12, 2005 7:00 am
Location: Portland, OR

Re: Open Downpipe

Post by Redlined »

Dunno about with turbo cars but I know on NA cars (specifically V-8s) you want to keep about a foot of pipe on after the head to prevent Cool air rushing in and warping your exhaust valves when you shut off after a hard run. Not quite the same thing but id worry about damage to the turbo/wastegate.

Just food for thought.
Dave
_________________
1993 Legacy Sport Sedan 4EAT "Angel" *sold*
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