how bad is the exhaust smell w/cats removed?

Singletrack · 12-16-2009, 10:00 PM

Quote:

Originally Posted by Nawaaz

Wow, that's actually pretty surprising!

I have the fabspeed HFCs, and the only time I smell my exhaust is at startup in the garage. I've never noticed any smell during any kind of driving.

H Bomb · 12-16-2009, 10:10 PM

i have the Dinan catless midpipe. mine isn't bad at all. if the window is down you can smell it a little bit when at a stop light but nothing horrible like some explained. maybe it is different with other brand pipes?? i haven't seen anyone behind me or on the side of me make any jestures or comments so i am assuming it isn't that bad. i am sure if i sat there and revved it then that would be different

MrHarris · 01-03-2010, 05:46 AM

The smell going catless is pretty bad. It sucks when it's a really nice day outside and you have the windows down but you're stuck at those 3 minute traffic lights..

WOT · 01-04-2010, 07:00 PM

Quote:

Originally Posted by MrHarris

Every stop light I smell my exhaust. It gets annoying after a while... which is why I'm putting in HFC's.

I've had experience with Riss Racing's 200cell HFC's and it took away the smell 100%.

MrHarris, Where are the Riss Racing HFCs located in your exhaust system ? I have an E93, and I want to get Fabspeed HFC and resonated X-pipe. I will mate this to a Vangaurd axle back. I can't remember where I read that placement of the HFCs is important to exhaust smell, but I recall reading that. My dad has a 1955 Chevy. It stinks up the whole shop. I really would like to aviod the stink bomb effect.

mvagusta · 01-18-2010, 10:16 PM

I wonder of the dinan 4 resonator's smell less than a hfc -x -pipe combo? Or is more?

Splinter4784 · 01-22-2010, 05:25 AM

I have the Rpi Gt Race Exhaust and it smells like a go kart

If my windows are down and im at a red light, i have to play the "how long can i hold my breath game" haha

As long as you keep your windows up and air con off at extended stops and lights, you should be good

King Tut · 01-22-2010, 10:13 AM

I also have the RPi GT Race Full Exhaust. I definitely smell like exhaust after driving my car for a decent length of time with the windows down. I don't hold my breath, but keeping the windows up and using the A/C I normally don't smell it.

AMPowerJ · 01-22-2010, 10:56 AM

Not bashing but just wondering is this really worth those few extra horses if you had to do it all over again? I ask because I was dead set on going catless or at least HFCs but I don't think I want my car to smell like a 1970 Oldsmabuick at every light.

miamie92m3 · 01-22-2010, 10:58 AM

I have the AA x-pipe with HFC's. No smell at all.

zamm3k · 01-22-2010, 11:03 AM

I have RPi's catless x pipes and the smell is pretty bad. To the point where I can't drive with windows down bcuz I'll intoxicate myself at stoplights. The price you pay!

King Tut · 01-22-2010, 03:27 PM

Quote:

Originally Posted by AMPowerJ

Not bashing but just wondering is this really worth those few extra horses if you had to do it all over again?

It's worth it. I don't drive the car for the luxury, I drive it for the performance.

Ben335 · 01-22-2010, 04:03 PM

Quote:

Originally Posted by mvagusta

I wonder of the dinan 4 resonator's smell less than a hfc -x -pipe combo? Or is more?

Any Catless will smell more than HFCs. Resonators don't catch any smell or fumes. They are only there for sound and drone reduction.

HFC at least will catch some of the gases and fumes.

Lemans_Blue_M · 01-22-2010, 08:05 PM

Quote:

Originally Posted by AMPowerJ

Not bashing but just wondering is this really worth those few extra horses if you had to do it all over again? I ask because I was dead set on going catless or at least HFCs but I don't think I want my car to smell like a 1970 Oldsmabuick at every light.

tightie · 01-22-2010, 11:29 PM

its not too bad... it depends which exhaust set up u go with of course.

eclipsisNA · 01-23-2010, 06:01 PM

I had a no cat straight pipe setup on my car for five days before I got hi-flow cats, and I got a headache every time I got in my car from the horrible exhaust fumes. The cats helped immensely but kept the sound the same, which is what I was after.

NatAsp-M3 · 02-27-2010, 04:41 PM

Quote:

Originally Posted by Eclipsis

I had a no cat straight pipe setup on my car for five days before I got hi-flow cats, and I got a headache every time I got in my car from the horrible exhaust fumes. The cats helped immensely but kept the sound the same, which is what I was after.

Headaches, Yikes!
Don't forget a lot of the catless exhaust is unconverted carbon monoxide which tightly binds hemoglobin. Carbon monoxide is actually odorless, but far more toxic than the gassy smell. Surely if you can smell the fumes, you're also getting too much carbon monoxide... the first symptom of which is a headache.

Maybe those running catless want to consider placing one of those home carbon monoxide monitors in their car, LOL!

MrHarris · 02-27-2010, 06:29 PM

Quote:

Originally Posted by WOT

MrHarris, Where are the Riss Racing HFCs located in your exhaust system ? I have an E93, and I want to get Fabspeed HFC and resonated X-pipe. I will mate this to a Vangaurd axle back. I can't remember where I read that placement of the HFCs is important to exhaust smell, but I recall reading that. My dad has a 1955 Chevy. It stinks up the whole shop. I really would like to aviod the stink bomb effect.

The Fabspeed HFC's are slightly farther up than Riss Racings HFC's. Not sure how it would affect smell, but the Riss, and now my current Gintani has NO smell.

swamp2 · 02-28-2010, 02:46 AM

Quote:

Originally Posted by PencilGeek

I have to turn on my recirc when I'm warming up the car -- just so I don't smell the exhaust.

Isn't it widely accepted that you should not or do not need to warm up any modern car while sitting still, stroker or not?

swamp2 · 02-28-2010, 02:48 AM

Quote:

Originally Posted by miamie92m3

My wife will soon figure out that its my car that smells like crap and decide she wants a prius to offset the emissions I'm throwing off.

Keep in mind that you can do more for the global warming cause by stoping your consumption of beef and dairy than by having a Prius over an M3. Really. Check the research!

Route 16 · 07-23-2018, 12:07 PM

Quote:

Originally Posted by eclipsisNA

I had a no cat straight pipe setup on my car for five days before I got hi-flow cats, and I got a headache every time I got in my car from the horrible exhaust fumes. The cats helped immensely but kept the sound the same, which is what I was after.

which hi-flow cats were those? I want to maintain sound while getting fumes gone.

Mvy · 07-23-2018, 03:01 PM

HFC plus resonators. Because the other bad thing about catless is raspy sounds. Vibrant has served me well in the past for HFC and I use magnaflow resonators and mufflers.

wyatth · 07-23-2018, 04:16 PM

A catless setup would sound like shit, smell like shit, and pollute unnecessarily given the lack of additional power over HFCs.
I am curious what smell exists with the primaries deleted, running only the secondaries or HFCs. Also curious how quality HFCs compare to the OE secondaries in terms of scrubbing (how well they convert pollutants and disrupt the raspy sound waves).
I really want to go stage 2, but am afraid of the volume/rasp and smell.

12-16-2009, 10:10 PM	#24
H Bomb Lieutenant Colonel 65 Rep 1,676 Posts Drives: 08 M3 Join Date: Jul 2007 Location: FL to NY iTrader: (4)	i have the Dinan catless midpipe. mine isn't bad at all. if the window is down you can smell it a little bit when at a stop light but nothing horrible like some explained. maybe it is different with other brand pipes?? i haven't seen anyone behind me or on the side of me make any jestures or comments so i am assuming it isn't that bad. i am sure if i sat there and revved it then that would be different __________________ Street- 08 E92 M3- Sparkling Graphite/ Fox Red/6sp Track- 10 CRF 250-PR2 Race Motor/Ohlins TTX Susp Hauler- 06 Ford Skyjacker F250 4WD
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01-03-2010, 05:46 AM	#25
MrHarris yodog 197 Rep 5,026 Posts Drives: '86 Corolla Join Date: Jun 2007 Location: Diamond Bar, Ca iTrader: (5) Garage List 2009 BMW [10.00]	The smell going catless is pretty bad. It sucks when it's a really nice day outside and you have the windows down but you're stuck at those 3 minute traffic lights.. __________________ 2009 E92 M3 \| Alpine White \| Black Extended \| Advan RS \| Turner Test Pipes \| Dinan Axle-Back \| OETuning \| Eibach Springs \| UUC SSK \| VRS Front Lip \| VRS Type I Diffuser \| Matte Black \| RPi Scoops \| MS Filter \| Yokohama AD08 \| F1 Pinnacle Special Thanks: Gintani \| OETuning \| eAs
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01-18-2010, 10:16 PM	#27
mvagusta Lieutenant 16 Rep 473 Posts Drives: 2008 m3 coup Join Date: Jun 2008 Location: michigan iTrader: (1)	I wonder of the dinan 4 resonator's smell less than a hfc -x -pipe combo? Or is more?
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01-22-2010, 05:25 AM	#28
Splinter4784 414 little horsies 56 Rep 405 Posts Drives: 2008 M3 Join Date: Jan 2009 Location: Beverly Hills iTrader: (2)	I have the Rpi Gt Race Exhaust and it smells like a go kart If my windows are down and im at a red light, i have to play the "how long can i hold my breath game" haha As long as you keep your windows up and air con off at extended stops and lights, you should be good __________________ Race Precision Inc
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01-22-2010, 10:13 AM	#29
King Tut NASA SpecE30 Racer 82 Rep 1,307 Posts Drives: 2006 Honda S2000 TT3 Join Date: Jul 2008 Location: Gulf Breeze, FL iTrader: (2)	I also have the RPi GT Race Full Exhaust. I definitely smell like exhaust after driving my car for a decent length of time with the windows down. I don't hold my breath, but keeping the windows up and using the A/C I normally don't smell it. __________________ King Tut 2012 BMW M3 Individual: Sold lsb.ridedomain.com 1987 BMW 325is SpecE30: spece30.ridedomain.com 2009 BMW M3 Coupe: Sold e92.ridedomain.com
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01-22-2010, 10:56 AM	#30
AMPowerJ One mod leads to another ... 415 Rep 2,900 Posts Drives: 2014 F10 M5 Join Date: Apr 2008 Location: Blythewood, SC iTrader: (10)	Not bashing but just wondering is this really worth those few extra horses if you had to do it all over again? I ask because I was dead set on going catless or at least HFCs but I don't think I want my car to smell like a 1970 Oldsmabuick at every light. __________________ Current: 2014 F10 M5 Previous: 2015 F80 M3, 2013 E92 M3, 2013 F10 M5, 2009 E90 M3, 1998 E36 M3
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01-22-2010, 10:58 AM	#31
miamie92m3 Private First Class 28 Rep 176 Posts Drives: M3 Join Date: Mar 2008 Location: Miami iTrader: (0)	I have the AA x-pipe with HFC's. No smell at all.
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01-22-2010, 11:03 AM	#32
zamm3k Bla! 82 Rep 909 Posts Drives: F82 M4 Join Date: Apr 2008 Location: Miami, FL iTrader: (4)	I have RPi's catless x pipes and the smell is pretty bad. To the point where I can't drive with windows down bcuz I'll intoxicate myself at stoplights. The price you pay! __________________ ......................::.........................
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01-22-2010, 11:29 PM	#36
tightie JOSH SHOKRI. 523 Rep 5,881 Posts Drives: 991 GT3RS, 964, Raptor Join Date: Aug 2005 Location: los angeles, california. iTrader: (7) Garage List 2008 BMW M3 [7.90]	its not too bad... it depends which exhaust set up u go with of course. __________________ Current: 16 991 GT3RS , 91 964 C2, 17 Raptor \| Past: 2015 991 GT3, 2015 i3,15 YMB F80 M3, 13 E92 M3 DCT, 08 E92 M3 6MT, 07 E60 M5, 02 E46 M3 Instagram: @josh_speeddistrict #SpeedDistrict @SpeedDistrict
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01-23-2010, 06:01 PM	#37
eclipsisNA Colonel 350 Rep 2,937 Posts Drives: 2013 Estoril 328i M Sport Join Date: Oct 2007 Location: Beverly Hills, CA iTrader: (6) Garage List 2014 BMW 428i [7.76]	I had a no cat straight pipe setup on my car for five days before I got hi-flow cats, and I got a headache every time I got in my car from the horrible exhaust fumes. The cats helped immensely but kept the sound the same, which is what I was after.
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07-23-2018, 03:01 PM	#43
Mvy Captain 540 Rep 979 Posts Drives: 2008 E93 M3 Join Date: Nov 2014 Location: GA Peach iTrader: (0)	HFC plus resonators. Because the other bad thing about catless is raspy sounds. Vibrant has served me well in the past for HFC and I use magnaflow resonators and mufflers. __________________ Harrop Supercharger, BPM Tune, K/W Coil over kit, Stoptek BBK, Magnaflow exhaust, ear to ear grin everytime I drive...
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07-23-2018, 04:16 PM	#44
wyatth Colonel 3549 Rep 2,823 Posts Drives: E90 ZCP Join Date: Dec 2007 Location: Bay Area iTrader: (0)	A catless setup would sound like shit, smell like shit, and pollute unnecessarily given the lack of additional power over HFCs. I am curious what smell exists with the primaries deleted, running only the secondaries or HFCs. Also curious how quality HFCs compare to the OE secondaries in terms of scrubbing (how well they convert pollutants and disrupt the raspy sound waves). I really want to go stage 2, but am afraid of the volume/rasp and smell.
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