Secondary Cat Delete/Removal Videos

stewey · 11-16-2015, 08:38 PM

Hi guys, finally took the plunge and removed the secondaries. This is a 2006 325i with an otherwise stock exhaust. The intake has subtle mods. Specifically the charcoal filter delete and a silicone intake boot from rev motoring. If you have a similar setup don't hesitate to do this mod. The sound change is very subtle and the butt dyno says: sure +9hp, I guess I can feel that.

BEFORE

AFTER

rich123321 · 11-16-2015, 10:49 PM

I paired mine with a muffler delete and it sounds amazing

stewey · 11-17-2015, 01:33 AM

Do you have a clip of it? Did you remove the secondaries, the resonator and the muffler? I'm worried that would be too loud for me.

gds52 · 11-18-2015, 10:54 AM

did you get any service engine light ?
I got SES light after secondary cats delete, waiting for my diagnostics tool and read the codes.
I also have AA tune and BMW performance exhaust on my 328i.

stewey · 11-21-2015, 11:00 PM

Nope, no check engine light. Yours might be for something else. There are no sensors after the secondaries so it shouldn't cause a CEL.

mg4734 · 11-22-2015, 11:00 AM

Where did you get your secondaries cut out? Would love to do this, but don't want to get harassed by a shop for wanting emissions equipment removed, or by the dealer if they notice this when I go there for the more complex services/repairs.

That335iGuy · 11-22-2015, 11:14 AM

great thread!

JasW · 11-23-2015, 05:50 AM

Quote:

Originally Posted by mg4734

Where did you get your secondaries cut out? Would love to do this, but don't want to get harassed by a shop for wanting emissions equipment removed, or by the dealer if they notice this when I go there for the more complex services/repairs.

Best place would be a custom exhaust shop. If you live in or near a large metro area, there's bound to be one. Failing that, a regular non-chain muffler shop. They're not going to harass you. As far as the dealer goes, it shouldn't be an issue unless you're coming in for something that's related to emissions.

I had my secondary cats deleted and replaced with Vibrant 1790 resonators, although not for sound/hp reasons, but to get rid of the rasp I had in the 4500-5500 RPM range after installing catless dps. It didn't get rid of the rasp -- something that's apparently the result of the 335is muffler paired with catless DPs -- but the sound is great.

Be warned about the stink with pump gas, though. It was really bad with catless DPs. I've since swapped out the catless DPs for catted, but there's still something of an odor running 93 octane with no secondaries. Running E60, no.

mg4734 · 11-23-2015, 08:27 AM

Quote:

Originally Posted by JasW

Best place would be a custom exhaust shop. If you live in or near a large metro area, there's bound to be one. Failing that, a regular non-chain muffler shop. They're not going to harass you. As far as the dealer goes, it shouldn't be an issue unless you're coming in for something that's related to emissions.

I had my secondary cats deleted and replaced with Vibrant 1790 resonators, although not for sound/hp reasons, but to get rid of the rasp I had in the 4500-5500 RPM range after installing catless dps. It didn't get rid of the rasp -- something that's apparently the result of the 335is muffler paired with catless DPs -- but the sound is great.

Be warned about the stink with pump gas, though. It was really bad with catless DPs. I've since swapped out the catless DPs for catted, but there's still something of an odor running 93 octane with no secondaries. Running E60, no.

Thanks, mostly concerned about the dealership so glad that shouldn't be an issue. I've stuck with catted dp's for now, just looking to get a bit more out of the PE mufflers.

stewey · 11-26-2015, 10:15 AM

I imagine it might depend on your dealer. I went for an inspection at the dealer a week after I had the secondaries removed and it was no issue. Actually, the only thing the service manager gave me a hard time about was the fact that I haven't done the three stage intake and tune yet

Route 16 · 11-26-2015, 10:58 AM

leaving a comment here so i can post my video later on today

11-16-2015, 08:38 PM	#1
stewey Second Lieutenant 71 Rep 246 Posts Drives: 2006 325i 6MT Join Date: Apr 2015 Location: Victoria, BC iTrader: (0)	Secondary Cat Delete/Removal Videos Hi guys, finally took the plunge and removed the secondaries. This is a 2006 325i with an otherwise stock exhaust. The intake has subtle mods. Specifically the charcoal filter delete and a silicone intake boot from rev motoring. If you have a similar setup don't hesitate to do this mod. The sound change is very subtle and the butt dyno says: sure +9hp, I guess I can feel that. BEFORE AFTER
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11-16-2015, 10:49 PM	#2
rich123321 Captain 72 Rep 838 Posts Drives: BMW 325i E90 Join Date: Jan 2012 Location: South Florida iTrader: (1) Garage List 2015 335i [0.00]	I paired mine with a muffler delete and it sounds amazing
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11-17-2015, 01:33 AM	#3
stewey Second Lieutenant 71 Rep 246 Posts Drives: 2006 325i 6MT Join Date: Apr 2015 Location: Victoria, BC iTrader: (0)	Do you have a clip of it? Did you remove the secondaries, the resonator and the muffler? I'm worried that would be too loud for me.
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11-18-2015, 10:54 AM	#4
gds52 Colonel 886 Rep 2,720 Posts Drives: BMW Z4M Coupe, BMW 328i E93 Co Join Date: Oct 2011 Location: NJ iTrader: (0)	did you get any service engine light ? I got SES light after secondary cats delete, waiting for my diagnostics tool and read the codes. I also have AA tune and BMW performance exhaust on my 328i.
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11-21-2015, 11:00 PM	#5
stewey Second Lieutenant 71 Rep 246 Posts Drives: 2006 325i 6MT Join Date: Apr 2015 Location: Victoria, BC iTrader: (0)	Nope, no check engine light. Yours might be for something else. There are no sensors after the secondaries so it shouldn't cause a CEL.
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11-22-2015, 11:00 AM	#6
mg4734 Lieutenant 28 Rep 409 Posts Drives: 2009 335i M-Sport Coupe Join Date: Dec 2012 Location: Illinois iTrader: (2)	Where did you get your secondaries cut out? Would love to do this, but don't want to get harassed by a shop for wanting emissions equipment removed, or by the dealer if they notice this when I go there for the more complex services/repairs. __________________ 2009 E92 335i M-Sport - MHD Stage One - BMW Performance Exhaust - BMS Oil Catch Can - CDV Delete - K&N Panel Filter - Arc Angel H8 bulbs - Gloss Black Kidney Grills - Painted Reflectors - VRSF Charge Pipe
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11-22-2015, 11:14 AM	#7
That335iGuy Private 3 Rep 84 Posts Drives: 2010 335i Join Date: Nov 2015 Location: Florida iTrader: (0)	great thread!
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11-26-2015, 10:15 AM	#10
stewey Second Lieutenant 71 Rep 246 Posts Drives: 2006 325i 6MT Join Date: Apr 2015 Location: Victoria, BC iTrader: (0)	I imagine it might depend on your dealer. I went for an inspection at the dealer a week after I had the secondaries removed and it was no issue. Actually, the only thing the service manager gave me a hard time about was the fact that I haven't done the three stage intake and tune yet
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11-26-2015, 10:58 AM	#11
Route 16 I got lei'd 844 Rep 7,593 Posts Drives: '10 E90 M3 Join Date: Sep 2011 Location: Dark Side of the Moon iTrader: (62)	leaving a comment here so i can post my video later on today
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