Downpipe produces a lot of smog

dominic828 · 11-26-2013, 10:21 PM

Hi, folks
I just installed VRSF dp few weeks ago and noticed that it produces a lot of smog and smelled so bad. I know that smelling bad is normal but wondering if producing a lot of smog is normal?

rdeterman · 11-26-2013, 10:26 PM

catless downpipes will do that.. plus you live in California.. smog is the norm

Sandman614 · 11-26-2013, 10:30 PM

Quote:

Originally Posted by rdeterman

plus you live in California.. smog is the norm

silver07335i · 11-26-2013, 10:56 PM

No catalytic converters on VRSF downpipes. You will fail smog with those so I hope you saved your stock downpipes for smog time.

dominic828 · 11-27-2013, 04:27 AM

OK, thanks for responding

Edogg218 · 11-27-2013, 01:06 PM

Quote:

Originally Posted by dominic828

Hi, folks
I just installed VRSF dp few weeks ago and noticed that it produces a lot of smog and smelled so bad. I know that smelling bad is normal but wondering if producing a lot of smog is normal?

I have an N54, and kept my stock midpipes with my VRSF DPs and Maddad whisper exhaust. It smells some, but I can't imagine how bad it would smell without any cats at all. Those days (350Z without cats back in the day) are over for me.

WedgePerformance · 11-27-2013, 01:27 PM

135Pats · 11-27-2013, 01:45 PM

Quote:

Originally Posted by WedgePerformance

When you remove the main piece of hardware dedicated to reducing emissions….you’ll have increased emissions.

11-27-2013, 01:50 PM

Pointless...I see no point in going catless on a car that is tag/titled for the street.

WedgePerformance · 11-27-2013, 02:08 PM

Quote:

Originally Posted by FCobra94

Pointless...I see no point in going catless on a car that is tag/titled for the street.

DP's help with performance and reduce back presser on the turbo, but removing the secondary cats I would agree. I made that mistake once and quickly put them back.

Tiago@VRSF · 11-27-2013, 02:27 PM

Quote:

Originally Posted by FCobra94

Pointless...I see no point in going catless on a car that is tag/titled for the street.

I disagree, it's an easy/cheap power mod that will keep your turbos healthy by the removal of backpressure and there are very few mods on this platform that can beat it hp per dollar.

11-27-2013, 02:34 PM

I understand that...I just can't see adding more pollutants to the environment for a couple more horsepower. Hardly worth the difference IMO. I'd rather find power in other ways.

If my stock DPs did require replacing, I'd probably go for high flow cat versions...or get catless versions and weld high flow stand alone cats downstream somewhere to supplement the secondaries lol tree hugger.

It would be interesting to see emmisons readings for each configuration though.

Lankster · 11-27-2013, 09:28 PM

Quote:

Originally Posted by silver07335i

No catalytic converters on VRSF downpipes. You will fail smog with those so I hope you saved your stock downpipes for smog time.

We are in the process of converting to DME testing only. So find a place that does that and you are good

808AWD325xi · 11-27-2013, 10:28 PM

Quote:

Originally Posted by FCobra94

It would be interesting to see emmisons readings for each configuration though.

Some recent CA readings:

http://www.e90post.com/forums/showpo...2&postcount=47

http://www.e90post.com/forums/showpo...9&postcount=54

Rotorocious · 11-28-2013, 10:39 AM

Lol at the tree hugger.

11-26-2013, 10:21 PM	#1
dominic828 Private 3 Rep 63 Posts Drives: BMW 335i coupe Join Date: Nov 2012 Location: San Francisco, CA iTrader: (0)	Downpipe produces a lot of smog Hi, folks I just installed VRSF dp few weeks ago and noticed that it produces a lot of smog and smelled so bad. I know that smelling bad is normal but wondering if producing a lot of smog is normal?
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11-26-2013, 10:26 PM	#2
rdeterman First Lieutenant 11 Rep 399 Posts Drives: 2008 335i Coupe 6mt Join Date: Apr 2012 Location: Iowa iTrader: (2)	catless downpipes will do that.. plus you live in California.. smog is the norm __________________ JB4 G5 ISO W/BMS FLASH, FBO, Walbro LPFP, Spec S2+ SMFW
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11-26-2013, 10:56 PM	#4
silver07335i Captain 25 Rep 755 Posts Drives: 335i titanium silver metallic Join Date: May 2013 Location: CA iTrader: (5)	No catalytic converters on VRSF downpipes. You will fail smog with those so I hope you saved your stock downpipes for smog time. __________________ Car: 2007 e90 335i 6MT - sports, premium, cold weather, light, and smoker's package. Performance Mods: Cobb AP v3, ETS 7" FMIC, Injen DCI, Michelin PSS, CDV delete, rear spoiler, BMW PE w/ Magnaflow tips, PTF pro-tune, VRSF downpipes, ER chargepipe w/ Tial Q, APEX 18" EC-7 wheels, MP outlet/ inlet, MMP Stg. 3 turbos. Other mods: BMW cargo liner, 20% window tint, BMW alarm system, Weathertech floorliner, Lux E90 V6 bulbs, Philips X-treme Vision H7 bulbs, Blackvue DR650GW-2CH.
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11-27-2013, 04:27 AM	#5
dominic828 Private 3 Rep 63 Posts Drives: BMW 335i coupe Join Date: Nov 2012 Location: San Francisco, CA iTrader: (0)	OK, thanks for responding
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11-27-2013, 01:27 PM	#7
WedgePerformance BimmerPost Supporting Vendor 1342 Rep 1,701 Posts Drives: Slot Machines.. Keep Taking $ Join Date: Oct 2013 Location: Portland, OR iTrader: (0) Garage List 2007 BMW 335i Sport [9.67]
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11-27-2013, 01:50 PM	#9
FCobra94 Guest 0 Rep n/a Posts Drives:	Pointless...I see no point in going catless on a car that is tag/titled for the street.
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11-27-2013, 02:34 PM	#12
FCobra94 Guest 0 Rep n/a Posts Drives:	I understand that...I just can't see adding more pollutants to the environment for a couple more horsepower. Hardly worth the difference IMO. I'd rather find power in other ways. If my stock DPs did require replacing, I'd probably go for high flow cat versions...or get catless versions and weld high flow stand alone cats downstream somewhere to supplement the secondaries lol tree hugger. It would be interesting to see emmisons readings for each configuration though.
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11-28-2013, 10:39 AM	#15
Rotorocious Lieutenant Colonel 105 Rep 1,520 Posts Drives: 335xi Join Date: May 2010 Location: Colorado iTrader: (3)	Lol at the tree hugger.
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