high flow cat placement question

anthonyrb98 · 04-13-2005, 04:15 PM

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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snvin · 04-13-2005, 04:51 PM

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?

anthonyrb98 · 04-13-2005, 05:51 PM

i don't really care about the environmental aspect (HA HA), I just need it to pass my yearly smog test.

Focus4 · 04-13-2005, 05:55 PM

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?

Gethin · 04-13-2005, 05:55 PM

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.

stircas · 04-13-2005, 06:05 PM

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.

Gethin · 04-13-2005, 06:10 PM

The Helix replaces the third stock cat too....it's full length.

anthonyrb98 · 04-13-2005, 06:15 PM

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.

Jimbo · 04-13-2005, 09:22 PM

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

anthonyrb98 · 04-17-2005, 04:01 PM

bumppp

silvscorp · 04-17-2005, 04:06 PM

put it where the stock 3rd cat is, right before your midpipe.

GoRacerXGo · 04-17-2005, 05:19 PM

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.

anthonyrb98 · 04-17-2005, 05:25 PM

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.

vitaminwrx · 04-17-2005, 06:30 PM

High flow cat, no matter where you place it, wont have a very big impact on overall performance.

04-13-2005, 04:15 PM	#1
anthonyrb98 Scooby Guru Member#: 48307 Join Date: Nov 2003 Chapter/Region: SCIC Location: san diego Vehicle: 02 bugeye hbspeed tuned 18g sleeper	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? * Registered users of the site do not see these ads.

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04-13-2005, 04:51 PM	#2
snvin Scooby Specialist Member#: 50578 Join Date: Dec 2003 Chapter/Region: Tri-State Location: -= /\ is awesome.=- Vehicle: 2009 2.5i. Bleh. -=Forza Azzurri=-	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?

04-13-2005, 05:51 PM	#3
anthonyrb98 Scooby Guru Member#: 48307 Join Date: Nov 2003 Chapter/Region: SCIC Location: san diego Vehicle: 02 bugeye hbspeed tuned 18g sleeper	i don't really care about the environmental aspect (HA HA), I just need it to pass my yearly smog test.

04-13-2005, 05:55 PM	#5
Gethin Scooby Specialist Member#: 2998 Join Date: Nov 2000 Chapter/Region: VIC Location: BC Vehicle: 2002 WRX WRB	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.

04-13-2005, 06:05 PM	#6
stircas Scooby Newbie Member#: 53886 Join Date: Jan 2004	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.

04-13-2005, 06:10 PM	#7
Gethin Scooby Specialist Member#: 2998 Join Date: Nov 2000 Chapter/Region: VIC Location: BC Vehicle: 2002 WRX WRB	The Helix replaces the third stock cat too....it's full length.

04-13-2005, 06:15 PM	#8
anthonyrb98 Scooby Guru Member#: 48307 Join Date: Nov 2003 Chapter/Region: SCIC Location: san diego Vehicle: 02 bugeye hbspeed tuned 18g sleeper	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.

04-13-2005, 09:22 PM	#9
Jimbo Scooby Newbie Member#: 28809 Join Date: Nov 2002 Location: Bay Area Vehicle: 2003 WRX Wagon Platinum Silver Metallic	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

04-17-2005, 04:01 PM	#10
anthonyrb98 Scooby Guru Member#: 48307 Join Date: Nov 2003 Chapter/Region: SCIC Location: san diego Vehicle: 02 bugeye hbspeed tuned 18g sleeper	bumppp

04-17-2005, 04:06 PM	#11
silvscorp Scooby Specialist Member#: 28480 Join Date: Oct 2002 Location: NJ	put it where the stock 3rd cat is, right before your midpipe.

04-17-2005, 05:19 PM	#12
GoRacerXGo Scooby Specialist Member#: 41605 Join Date: Aug 2003 Chapter/Region: SCIC Location: San Diego, CA Vehicle: 2003 STG 4 WRX Sedan Sonic Yellow	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.

04-17-2005, 05:25 PM	#13
anthonyrb98 Scooby Guru Member#: 48307 Join Date: Nov 2003 Chapter/Region: SCIC Location: san diego Vehicle: 02 bugeye hbspeed tuned 18g sleeper	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.

04-17-2005, 06:30 PM	#14
vitaminwrx Scooby Newbie Member#: 46978 Join Date: Nov 2003	High flow cat, no matter where you place it, wont have a very big impact on overall performance.