[neroneuman]

Hello Guys,

I'm really confused on whether to put a Downpipe in my E90 335i.

I have been reading the forum that with Catless/Catted Downpipes, the car cant pass smog.

But the power gains cant be fully realized without Downpipes.

I have smog two years away but then I cant do the DP install myself and thinking do I need to spend $150 everytime to swap the pipes


for all the Norcal guys running DPs , do you swap out before smog or is there any other solution?

[mythek]

hey man, having aftermarket downpipes will most likely fail smog test.

here are two easier solutions:

1) buy a downpipe fix (cost like $60-100) and can be used to pass many smog checks
2) just pay a shop $120-150 so they can pass the smog for you

swapping out downpipes should be considered only when you can do it yourself.

[neroneuman]

Cool.

I will go with downpipes and the DP fix

[s!ke]

Yeah dp swaps from a shop are $350-500

Use the downpipe fix, and cross your fingers. Hopefully they won't catch it not ready if the DP fix doesnt work.

[Maximo'sE82]

If u lived in SoCal I can do the DP swap for $100

[mikex25]

If you can get a dp install for 150, mind sharing where?

[neroneuman]

I was referring to Rob in Anaheim.

http://www.n54tech.com/forums/showthread.php?p=324778.

[Me333]

What about the new smog law that they will only download info from the ecu? Will they not get more info about how you've been driving the whole time? Unless you reset the ecu back to stock, but I don't know if that clears all the logs. If you could clear it back to stock, but then it would still know you don't have chatted pipes...not sure how to resolve this. You need at least 50 miles of the ecu of data so you don't fail smog. I failed once because I didn't drive the car for a month and it just sat there.

[mythek]

Originally Posted by Me333

What about the new smog law that they will only download info from the ecu? Will they not get more info about how you've been driving the whole time? Unless you reset the ecu back to stock, but I don't know if that clears all the logs. If you could clear it back to stock, but then it would still know you don't have chatted pipes...not sure how to resolve this. You need at least 50 miles of the ecu of data so you don't fail smog. I failed once because I didn't drive the car for a month and it just sat there.

i know in california they do obd test (ecu). even so, you just cannot pass smog test by simply clearing all the error codes before going to the test. Even when there's no active error, your car will not pass if it's not "READY". To be in ready state your car must be driven a certain distance....and by the time your car is ready, all of those error codes will come back.

[Me333]

Originally Posted by mythek

i know in california they do obd test (ecu). even so, you just cannot pass smog test by simply clearing all the error codes before going to the test. Even when there's no active error, your car will not pass if it's not "READY". To be in ready state your car must be driven a certain distance....and by the time your car is ready, all of those error codes will come back.

I don't see anyway out of getting away with it. what about those catted DPs? I know some vendors have catted down pipes, but I heard they will not pass either. Any one have catted down pipes and passed smog ? I want to put dps too, but I don't want to be screwed by changing them out every 2 years, then annually after 10 years (I think that's the rule).

Anyone have any ideas about catted down pipes?

[Fundguy1]

Move to FL. No emissions test or inspection either. No state income tax and buy all the high capacitymagazines filled with hollow points you want for your conceal carry weapon of choice.

[Fundguy1]

I never understood why they wouldn't let you pay a waiver fine for emissions like say $100 a year and then use the money to pay for some clean energy projects like windmills. But then again I'm the guy with the bumper sticker over his armada's tailpipe that reads I'm changing the environment, ask me how.

[LSx]

Originally Posted by Me333

I don't see anyway out of getting away with it. what about those catted DPs? I know some vendors have catted down pipes, but I heard they will not pass either. Any one have catted down pipes and passed smog ? I want to put dps too, but I don't want to be screwed by changing them out every 2 years, then annually after 10 years (I think that's the rule).

Anyone have any ideas about catted down pipes?

I've read a few posts stating that the Wagner catted DP doesn't throw codes...haven't seen anyone talk about trying to pass the sniffer with one yet, but that shouldn't be an issue anymore because of the way the DADS smog check will work.

I'd love to see some real info on what the Wagner does for turbo spool, throttle response, and power compared to the catless DPs.

[Me333]

Originally Posted by Fundguy1

Move to FL. No emissions test or inspection either. No state income tax and buy all the high capacitymagazines filled with hollow points you want for your conceal carry weapon of choice.

As lovely as that sounds, moving to Florida is not a viable alternative based in reality. And frankly, I don't want to be around people with high capacity magazines or hollow points or people that conceal carry weapons. I have a job, houses, family (including children), etc, that are all in California. I don't think that my family will be ok with moving so I can have downpipes (reality check).

So I need a viable option based in reality. If anyone has working down pipes that have passed smog in CA, please say so, and I will happily buy those from that manufacturer. Has anyone tried a custom build that includes cats that has passed smog? I feel like everyone just changes dPs to stock or buys their way out of it. I'm fine with the $$ but who will do that now since they will see everything on the OBD?
No way OUT!!

[yas_e92]

VRSF has a dp fix that passes emissions. I have 08 335xi with vrsf catless dp and the fix. going to get my emissions done soon too lol hope it works

[shadow191]

The resolution is the DPFix. It alters the voltage from your rear O2 so your ECU doesn't know there's no cats there. Basically install DPFix, clear your codes and drive around or do the drive cycle. Eventually, all of your monitors will show ready and then you take it in to get checked. If all your monitors are ready and you have no codes, you'll pass.

If you don't use a DPFix and have catless DP's, you'll throw a code as soon as the readiness checks finish.

Catted downpipes will likely still throw a code since the cats are high flow and not as efficient as OEM. The voltage will still be off on the rear O2.

Originally Posted by Me333

What about the new smog law that they will only download info from the ecu? Will they not get more info about how you've been driving the whole time? Unless you reset the ecu back to stock, but I don't know if that clears all the logs. If you could clear it back to stock, but then it would still know you don't have chatted pipes...not sure how to resolve this. You need at least 50 miles of the ecu of data so you don't fail smog. I failed once because I didn't drive the car for a month and it just sat there.

[jmbillsta]

I think i may be the only Californian that passed the functional inspection with dpfix only to fail the visual. Now contemplating whether to visit another shop or revert back to stock. Feeling the pain fellas

[princelybug]

Interested to see if someone has a reliable & viable solution.

[888Concept]

same my registration is expiring in july and it's time for smog check again. I have DPFix but my car really smell so bad, I'm afraid theyre gunna fail me anyway.

[tc535i]

can I borrow someone's DP fix? Got a smog due in 2 weeks :/

[Fundguy1]

Originally Posted by Me333

As lovely as that sounds, moving to Florida is not a viable alternative based in reality. And frankly, I don't want to be around people with high capacity magazines or hollow points or people that conceal carry weapons. I have a job, houses, family (including children), etc, that are all in California. I don't think that my family will be ok with moving so I can have downpipes (reality check).

So I need a viable option based in reality. If anyone has working down pipes that have passed smog in CA, please say so, and I will happily buy those from that manufacturer. Has anyone tried a custom build that includes cats that has passed smog? I feel like everyone just changes dPs to stock or buys their way out of it. I'm fine with the $$ but who will do that now since they will see everything on the OBD?
No way OUT!!

War is the answer, especially for guys who think God wants them to take over the world and who want you to do what they say or they will cut off your head. Introduce them to their 40 virgins. Sorry you prefer to hang around in a group where only the criminals have the guns and the cops investigate why you and your family were murdered instead of you standing a chance of surviving. That said, go catless, pay whatever fine, swap if needed to pass, then move on. If the DP fix works then great. But don't forget you'll be adding to global warming without cats. That's the biggest threat to the nation and the world right now lol. Back to burning trash.