flat flange dpipe & Cobb cat back
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flat flange dpipe & Cobb cat back
As many of you know, Cobb is backed up in getting their downpipes out to cuStomers. I received everything but the down pipe for their Stage II package. I have to admit, the cat back looks beautiful. Anywho, I have been waiting on the down pipe for six months and have run out of patience. The Cobb guys are great, but said it will still be another two months, so I have two quick questions (and I have searched the forums already):
1. Will a Down Pipe with a Cat such as Helix or TurboXS with a cat in the down pipe keep you street legal. If not, I might as well get a pipe without a cat.
2. Since Cobb uses a bell mouth, I want to keep in the same vein so that I can continue to use their Access Port maps. I want to get the Helix pipe, but I believe it has a flat flange (Group-S could not give me a definitive answer except "it should be ok"). Has anyone used this with their stock exhaust? I ask because the Cobb cat back is supposed to fit the stock down pipe. This means you have to use the 3" doughnut gasket, but I do not know how this would fit with a flat flanged Helix Pipe which seems to be the most popular after TurbosXS. The TurboXS downpipe and cat combo apparently will not fit with a stock exhaust, and you would have to get the "Stealth" exhaust without a cat to fit with a stock exhaust ergo, the same connection that Cobb uses.
If the answer to question #1 is that a cat will not help you pass inspection, then I can a non cat pipe from either Helix or TurboXS. I will just keep my old stuff to swap out once a year for inspection.
Thanks in advance !!!!!!!!!!!!!!!!!!!!!!!!!!!!!
1. Will a Down Pipe with a Cat such as Helix or TurboXS with a cat in the down pipe keep you street legal. If not, I might as well get a pipe without a cat.
2. Since Cobb uses a bell mouth, I want to keep in the same vein so that I can continue to use their Access Port maps. I want to get the Helix pipe, but I believe it has a flat flange (Group-S could not give me a definitive answer except "it should be ok"). Has anyone used this with their stock exhaust? I ask because the Cobb cat back is supposed to fit the stock down pipe. This means you have to use the 3" doughnut gasket, but I do not know how this would fit with a flat flanged Helix Pipe which seems to be the most popular after TurbosXS. The TurboXS downpipe and cat combo apparently will not fit with a stock exhaust, and you would have to get the "Stealth" exhaust without a cat to fit with a stock exhaust ergo, the same connection that Cobb uses.
If the answer to question #1 is that a cat will not help you pass inspection, then I can a non cat pipe from either Helix or TurboXS. I will just keep my old stuff to swap out once a year for inspection.
Thanks in advance !!!!!!!!!!!!!!!!!!!!!!!!!!!!!
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Joined: Feb 2004
Posts: 720
From: The Hunted Forest
Car Info: Mazda Protege '02 (Wishing protege has AWD and a H6 twin turbo)
Street legal depends on where you live.
In california i believe taking the cats out is not legal but it would probably pass their sniffer test and thus pass alot of other states becuase they don't inspect for aftermarket parts.
If you want to mate the helix up to something not a flat pipe flange 3" metal then you will probably have to do some welding. I really should have taken pictures of the last full tbe + up pipe system i had the pleasure to install.
It was helix up and down pipe which fit awesome imo. Had to weld a 3" sleeve onto the downpipe's flat flange (thought it was the easiest method) to attach a borla hush catback twin tip. Which clamped right onto the 3" sleeve with no leaks i could find.
I suppose you will have to weld somethin on the downpipe to fit a catback to it.
In california i believe taking the cats out is not legal but it would probably pass their sniffer test and thus pass alot of other states becuase they don't inspect for aftermarket parts.
If you want to mate the helix up to something not a flat pipe flange 3" metal then you will probably have to do some welding. I really should have taken pictures of the last full tbe + up pipe system i had the pleasure to install.
It was helix up and down pipe which fit awesome imo. Had to weld a 3" sleeve onto the downpipe's flat flange (thought it was the easiest method) to attach a borla hush catback twin tip. Which clamped right onto the 3" sleeve with no leaks i could find.
I suppose you will have to weld somethin on the downpipe to fit a catback to it.
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Thanks for the reply! This means I will have to find someone who can weld. My area is not know for being modifier friendly at all and fabrication is not my area.
I was able to get a picture of the Cobb flange. Take a look at the attachment. Since you have seen both Helix and the Borla flange, did the Borla Flange look anything like the Cobb in the attached picture?
Thanks!
I was able to get a picture of the Cobb flange. Take a look at the attachment. Since you have seen both Helix and the Borla flange, did the Borla Flange look anything like the Cobb in the attached picture?
Thanks!
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Car Info: Evo X, 04 STI, 335i, Fit
Runningman-
-I'm not sure where you live, but in California, any modifications to the Catalytic converters (like switching them for high-flow aftermarket ones) are illegal.
-As for the Helix Downpipe mating properly to a Cobb Catback, yes it will w/o modifications. We have installed for customers a Cobb Catback mated to a Helix Up & Downpipe combo w/ no problems at all. Feel free to PM or shoot me an E-mail at soren@mpjperformance.com if you have any more questions.
-Soren
-I'm not sure where you live, but in California, any modifications to the Catalytic converters (like switching them for high-flow aftermarket ones) are illegal.
-As for the Helix Downpipe mating properly to a Cobb Catback, yes it will w/o modifications. We have installed for customers a Cobb Catback mated to a Helix Up & Downpipe combo w/ no problems at all. Feel free to PM or shoot me an E-mail at soren@mpjperformance.com if you have any more questions.
-Soren
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