[BimmerF32_430i]

I was thinking of getting a downpipe but I don't want to deal with the smell, however, I know going the catted way is going to be expensive. Is there a catless downpipe that y'all recommend that doesn't smell as bad as others? How about a catted downpipe?

Also, I don't want to run a tune so I was thinking of doing the BMS canflap to delete codes. Is there a cheaper way to simply delete the cel that the dp will throw?

I just mainly want the dp for sound and not performance.

[R32DBP]

Any catless dp will be the same. Pipe is pipe. Just paying for a name IMO for a catless pipe. They will all smell. In terms of defeating the CEL you can get an o2 spacer but idk how long that will last you. Your best bet will be the can flap module I believe. I'm not too familiar with it but I've heard it's the way to go to get rid of CEL without a tune. I have a Enzo Performance tune on my car and it's definitely worth it. The increase in power is amazing. Paired with the catless dp and your golden.

[BimmerF32_430i]

Originally Posted by R32DBP

Any catless dp will be the same. Pipe is pipe. Just paying for a name IMO for a catless pipe. They will all smell. In terms of defeating the CEL you can get an o2 spacer but idk how long that will last you. Your best bet will be the can flap module I believe. I'm not too familiar with it but I've heard it's the way to go to get rid of CEL without a tune. I have a Enzo Performance tune on my car and it's definitely worth it. The increase in power is amazing. Paired with the catless dp and your golden.

Have you had experience with VRSF? It's the cheapest one that I see but I still see the majority running ER.

[Nickon]

I have the ER downpipe. sounds great. performs well. love it but you should definitely get a tune IMO you wont regret it at all

[G30 B58]

Originally Posted by chaudhrysn

I was thinking of getting a downpipe but I don't want to deal with the smell, however, I know going the catted way is going to be expensive. Is there a catless downpipe that y'all recommend that doesn't smell as bad as others?

Also, I don't want to run a tune so I was thinking of doing the BMS canflap to delete codes. Is there a cheaper way to simply delete the cel that the dp will throw?

I just mainly want the dp for sound and not performance.

Get a Shiftek catless dp and a JB4 for under $800 total. Anyone with a Fisher-Price set of tools can install these two items. Enjoy the extra 80hp and 100 ft/lbs of torque. No CEL and you'll still have the CANflap even though you won't use it.

It will smell, no way around it.

[BimmerF32_430i]

Originally Posted by F32 N55

Get a Shiftek catless dp and a JB4 for under $800 total. Anyone with a Fisher-Price set of tools can install these two items. Enjoy the extra 80hp and 100 ft/lbs of torque. No CEL and you'll still have the CANflap even though you won't use it.

It will smell, no way around it.

But then I'll need a chargepipe as well. Trying to keep it all under $500

[G30 B58]

Originally Posted by chaudhrysn

But then I'll need a chargepipe as well. Trying to keep it all under $500

BS. Your charge pipe might break while you're stock. I bought one, it's in the trunk, in the box, uninstalled.

You don't NEED a charge pipe.

[BimmerF32_430i]

Originally Posted by F32 N55

BS. Your charge pipe might break while you're stock. I bought one, it's in the trunk, in the box, uninstalled.

You don't NEED a charge pipe.

Yeah but I think I'd rather play it safe and have it on instead of hoping it doesn't bust and then being stuck on the side of the road one day. Either way I have no need for a tune. Simply looking for an increase in sound and a way to delete the cel without a tune.

[Buckeyes]

Everyone needs a tune, they just don't know it yet.

[BimmerF32_430i]

Originally Posted by Trcb777

Everyone needs a tune, they just don't know it yet.

Well this is obviously becoming a pointless thread. Let's get everyone who wants to tell me to get a tune out of the way so someone can actually help me out.

All I simply want is advice on a catted or catless downpipe that doesn't smell. So I now know catless down pipes are going to smell no matter what, so if someone who has a catted downpipe wants to chime in on how bad the smell is, please let me know. Is it going to be less than a catless downpipe?

[Tech567]

Okay, well just helping you with wording, a "cat- less" downpipe is simply called a downpipe...other than that theres a catalytic converter or a high-flow catalytic converter. Getting a high-flow cat would help reduce the exhaust smell...but you won't make the same numbers or sound as a downpipe so it remains kinda pointless in your case if you're not trying to spend money. Go to a local muffler shop and see if they have a custom high-flow cat for you. That would be your cheapest route.

[RoundelM3]

OP: Actually, a downpipe can be just that with or without a catalytic converter. There are downpipes with high-flow catalytic converters and those with the catalyst removed altogether. A "catted" downpipe would have a catalytic converter with less restriction and likely be slightly larger in diameter as well. There's a secondary catalytic converter further down the exhaust system where the downpipe connects to the center section. The purpose of the "cat" as it's called is to burn any unburned hydrocarbons in the exhaust stream. If you remove or reduce the amount of catalyst material, the exhaust will have more of an odor than it would with both cats intact. So a catted downpipe will give you more flow, but there'll be a bit more smell (stand behind a '60's musclecar with the engine running and you'll understand what it's like). The early catalytic converter cars from the mid-1970s had a really horrible rotten-egg smell back when gasoline had lots of sulfur in it, and there was a distinct "burnt" smell as well. Low-sulfur gasoline and better catalyst materials have reduced that significantly, but any time you modify or remove one or both of the catalysts, it's going to smell quite a bit. Depending on where you live, you may or may not pass inspection, specifically if they use a tailpipe sniffer instead of just checking the OBDII output for a "ready" status. I recall that there is also a $10K fine for "tampering with federally-mandated emissions equipment", although I've not heard of anyone or any shop getting nailed for that.

[Buckeyes]

I think Volkswagen will be getting a fine slightly larger then $10k. Hahaa.

The n55 335i has only one cat.

[Jadar]

If you want a catless downpipe without the smell lol it's not gonna happen. There is no converter hence it will stink like a skunk.

Even Hiflow catted ones have a bit of a smell because they have a 200cel design for high flow instead of 800.

It's the price you gotta pay for sound and power. Not sure what else to tell ya.

[zerreissen]

The smell with a cat-less down-pipe on this car really isn't that bad; I rarely notice it except when I'm backing the car into the garage.

[BimmerF32_430i]

Originally Posted by roundel335

OP: Actually, a downpipe can be just that with or without a catalytic converter. There are downpipes with high-flow catalytic converters and those with the catalyst removed altogether. A "catted" downpipe would have a catalytic converter with less restriction and likely be slightly larger in diameter as well. There's a secondary catalytic converter further down the exhaust system where the downpipe connects to the center section. The purpose of the "cat" as it's called is to burn any unburned hydrocarbons in the exhaust stream. If you remove or reduce the amount of catalyst material, the exhaust will have more of an odor than it would with both cats intact. So a catted downpipe will give you more flow, but there'll be a bit more smell (stand behind a '60's musclecar with the engine running and you'll understand what it's like). The early catalytic converter cars from the mid-1970s had a really horrible rotten-egg smell back when gasoline had lots of sulfur in it, and there was a distinct "burnt" smell as well. Low-sulfur gasoline and better catalyst materials have reduced that significantly, but any time you modify or remove one or both of the catalysts, it's going to smell quite a bit. Depending on where you live, you may or may not pass inspection, specifically if they use a tailpipe sniffer instead of just checking the OBDII output for a "ready" status. I recall that there is also a $10K fine for "tampering with federally-mandated emissions equipment", although I've not heard of anyone or any shop getting nailed for that.

I'm just used to saying catless and catted haha In my area they don't test for it so I should be good for now. Thanks for the help. I'll try out a catless dp and if the smell is bad I'll try out a catted and see how it is.

Thanks for the help everyone

[Jadar]

Originally Posted by zerreissen

The smell with a cat-less down-pipe on this car really isn't that bad; I rarely notice it except when I'm backing the car into the garage.

Pretty much my experience as well, only on cold starts is it really bad. Other then that I'd stick wi what I got is never go for a true catless dp. Yes the gains are more but I me 10 more hp is just not that much more to me to jump up and down about.

[kdog26372]

I've got Fabspeed catted downpipe and there is no extra smell that I can perceive from this mod. The power gains aren't that far off from catless; so far no CEL either, and I believe they recently updated the catted version to further avoid CEL. But if extra power and no extra smell is what you want, then this would be a good option from personal experience.

[zerreissen]

Originally Posted by dd1981

Pretty much my experience as well, only on cold starts is it really bad. Other then that I'd stick wi what I got is never go for a true catless dp. Yes the gains are more but I me 10 more hp is just not that much more to me to jump up and down about.

But the cat-less was just so much cheaper... http://www.ebay.com/itm/Shifteck-N55...1fd94c&vxp=mtr

[Jadar]

Originally Posted by zerreissen

But the cat-less was just so much cheaper... http://www.ebay.com/itm/Shifteck-N55...1fd94c&vxp=mtr

Yep totally get that. Combine that with more hp gains I'm sure it's why most run that setup.

[R32DBP]

Originally Posted by chaudhrysn

Have you had experience with VRSF? It's the cheapest one that I see but I still see the majority running ER.

I actually have the VRSF dp on my car. Just got it installed a couple weeks ago and the quality is spot on. You wont be disappointed in the quality of the VRSF plus it has lifetime warranty. I posted a thread not too long ago and how it sounds after I installed it.

[mike@x-ph.com]

Originally Posted by chaudhrysn

I was thinking of getting a downpipe but I don't want to deal with the smell, however, I know going the catted way is going to be expensive. Is there a catless downpipe that y'all recommend that doesn't smell as bad as others? How about a catted downpipe?

Also, I don't want to run a tune so I was thinking of doing the BMS canflap to delete codes. Is there a cheaper way to simply delete the cel that the dp will throw?

I just mainly want the dp for sound and not performance.

All downpipes will smell the same as long as you are getting a good brand.

Most smell issues i see are because the downpipes are cheap and do not fit 100%