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Old 04-13-2005, 04:15 PM   #1
anthonyrb98
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Default high flow cat placement question

just got a magnaflow high flow cat and was wondering if i can put it post downpipe? i have a full helix and i don't want to have the cat welded onto it. would it be ok the have it welded just right after my helix downpipe with the catback?
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Old 04-13-2005, 04:51 PM   #2
snvin
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If it fits in that location, you COULD do it, and the farther back you put it the less of a restriction it becomes - BUT the farther back you put it the longer it takes to "light off" the catalyst, so puting it closer to the turbo means the catalyst can do its environmental job better.
Does that make sense?
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Old 04-13-2005, 05:51 PM   #3
anthonyrb98
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i don't really care about the environmental aspect (HA HA), I just need it to pass my yearly smog test.
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Old 04-13-2005, 05:55 PM   #4
Focus4
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Quote:
Originally Posted by anthonyrb98
i don't really care about the environmental aspect (HA HA), I just need it to pass my yearly smog test.
well if you want it to pass shouldn't it be able to do its job?
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Old 04-13-2005, 05:55 PM   #5
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Let me know the results if u get it soon as i'm planning a similar setup later this year. I've got a metal substrate 3" cat going into the midpipe right after the Helix.
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Old 04-13-2005, 06:05 PM   #6
stircas
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put it where the stock 3rd cat was you will be fine for the test.i know from experience and before the o2 sensor and no cel's. if there not all ready taken care of.
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Old 04-13-2005, 06:10 PM   #7
Gethin
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The Helix replaces the third stock cat too....it's full length.
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Old 04-13-2005, 06:15 PM   #8
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yeah, i really don't want to hack up my helix. i'd rather have the cat welded into my catback just right after where the dp and catback bolt up.
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Old 04-13-2005, 09:22 PM   #9
Jimbo
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Not sure how the helix is, but the scoobysport is similar to stock with two mid-pipes, so I had my Magnaflow welded in the front mid-pipe which is same as the stock location.

Jim
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Old 04-17-2005, 04:01 PM   #10
anthonyrb98
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bumppp
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Old 04-17-2005, 04:06 PM   #11
silvscorp
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put it where the stock 3rd cat is, right before your midpipe.
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Old 04-17-2005, 05:19 PM   #12
GoRacerXGo
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I have a random tech setup. It has no cat in the downpipe, and a cat in the 3rd pipe (before the catback). I got it for this same reason, I wanted there to be less turbulence going into the cat, and it being less restrictive. But I can see how the theory of the cat not "lighting up" could be possible. You should check it out. It's a great product.
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Old 04-17-2005, 05:25 PM   #13
anthonyrb98
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well, my real question is whether or not there will be a big difference in terms of performance and the whole smog issue if i weld it into my helix dp where the 3rd cat would be or just right after in my catback piping. the main reason is that it would just be easier to take off the catback and have the cat welded into it than having to take off the downpipe to get the cat welded in.
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Old 04-17-2005, 06:30 PM   #14
vitaminwrx
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High flow cat, no matter where you place it, wont have a very big impact on overall performance.
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