how bad is the exhaust smell w/cats removed?

[Fen335i]

I keep reading about folks complaining about the smell of their exhaust systems for those that have removed their cats. Just curious how bad it is. Is it a terrible rotten-egg type smell or is is just the smell of a normal exhaust, but just a lot stronger??


Also, does the smell enter the interior of the cabin easily (with windows closed)?

[CanM3]

I only smell it occasionally....just a whiff of exhaust when the windows down...not a real big deal. Usually noticeable after stopping at a light

[Alias]

Its just a strong exhaust smell

[M3 Montreal]

Originally Posted by Fen335i

I keep reading about folks complaining about the smell of their exhaust systems for those that have removed their cats. Just curious how bad it is. Is it a terrible rotten-egg type smell or is is just the smell of a normal exhaust, but just a lot stronger??


Also, does the smell enter the interior of the cabin easily (with windows closed)?

It's pretty bad on the outside...

I barely ever smell anything inside the car but people behind and outside DO . You definately dont want a cop car anywhere near you and Ive had some people at stoplights pinch their nose and point at my car.

[Singletrack]

Pretty damn bad. Even with my HFCs, at startup, the smell is pretty unbearable if you are standing behind the car - like loading up the trunk. In my case, it is not a rotten egg smell, just very pungent exhaust smell.

[BimmerRob08]

I've got the Encore xpipe installed with HFC and it's a noticable difference than stock. But I work around aircraft and engine exhausts allot so I might not be as sensitive to it. But I personnely don't think it's a huge difference, just a bit stronger exhaust smell. No one has complained yet to me so far.

[Fen335i]

thanks to all of you for your responses...very helpful information.

[miamie92m3]

yep. I agree. Smells bad from the outside. Not really noticeable on the interior. My garage now smells like a lawn mower. 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.

[Eugene-TAIWAN]

Its pretty bad on cold starts. But once it gets going it NOT that bad..... well then again maybe because I am always in the drivers seat.

[Ca$hOnly]

Originally Posted by M3 Montreal

It's pretty bad on the outside...

I barely ever smell anything inside the car but people behind and outside DO . You definately dont want a cop car anywhere near you and Ive had some people at stoplights pinch their nose and point at my car.

LOL

[Singletrack]

Originally Posted by Ca$hOnly

LOL

LOL!

What Montreal said really is funny.

All I know is that I rode behind my buddy's WRX after we put a full catless exhaust on and it was awful - I had to change lanes to try to escape the smell.

[xxe92xx]

its all about the smell

[JCtx]

Originally Posted by Fen335i

Is it a terrible rotten-egg type smell or is is just the smell of a normal exhaust, but just a lot stronger??

The 'rotten-egg' smell is when you're poisoning the cats. Without cats, there's no such odor. But it smells like crap, and it stays in your clothes. And the richer your engine is running, the worse its smells. Definitely not 'green' .

[graider]

that's the thing with delete the cat.

[chungdae]

If you have ever been at the race track with all the high performance cars zooming by, the rancid gasoline/exhaust smell is pretty much what it smells like.

[FStop7]

With no cats it smells like some redneck's ratted out 1988 Monte Carlo.

[Nawaaz]

I guess I'm ok with the smell. I mean I don't prefer it, but I knew how it would be before getting a full exhaust on my M, since I had one on my previous car.

I honestly feel it's not too big of a deal if you're the one inside the car driving.....Unless you're just super-sensitive.

[mvagusta]

is it 50 percent less smell with hfc's then a catless exhaust?

[Nawaaz]

Originally Posted by mvagusta

is it 50 percent less smell with hfc's then a catless exhaust?

I personally haven't experienced hfc's, but I don't think it would be 50% less.

I'm thinking maybe...20-25%?

[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%.

[Nawaaz]

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%.

Wow, that's actually pretty surprising!

[igom3]

Originally Posted by Alias

Its just a strong exhaust smell

BS