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Legal exhaust system? DP's?
I'd like to plan out an exhaust upgrade. I've looked into the legality of what I can do and I think the Akrapovic evolution exhaust will do fine since it's legal (i believe? It doesn't get rid of the CAT), what I'm having trouble with is downpipes. Are all of them pretty much illegal? I've looked at the magnaflow but it doesn't really seem to make a difference though. I'd like to be able to pass any emission's test. I saw the mod that takes the O2 sensor a bit farther back. Would this allow the car to pass?
Edit: I'm also open to any other good legal exhaust systems that you might recommend, and also forgot to mention the delete-r for the downpipe code. |
What state are you in?
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Depends where you live. If Cali, then go with the NM engineering exhaust. The 2nd cat is still there and you can choose if you want a resonator or not. Also the FJCW exhaust is nice.
If you don't live in Cali then there's Millitek, NM(delete 2nd cat), DDM exhaust, and the FJCW exhaust. I had the magnaflow and it sucked. I like the FJCW exhaust I put on. I deleted the 2nd cat and resonator and it is perfect for everyday commuting. |
Originally Posted by CarlosDMotor
(Post 3862807)
What state are you in?
Originally Posted by RobMuntean
(Post 3862819)
Depends where you live. If Cali, then go with the NM engineering exhaust. The 2nd cat is still there and you can choose if you want a resonator or not. Also the FJCW exhaust is nice.
If you don't live in Cali then there's Millitek, NM(delete 2nd cat), DDM exhaust, and the FJCW exhaust. I had the magnaflow and it sucked. I like the FJCW exhaust I put on. I deleted the 2nd cat and resonator and it is perfect for everyday commuting. |
I think it is illegal to remove any cat if it is there from the factory. I think it's a federal law not state law.
That being said, I don't think they'll come knocking down your door. |
Originally Posted by cerenkov
(Post 3862850)
I think it is illegal to remove any cat if it is there from the factory. I think it's a federal law not state law.
That being said, I don't think they'll come knocking down your door. |
Originally Posted by Scooby Doo
(Post 3862853)
What do I need to worry about when emissions test comes around?
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Ah ok thanks. Have you had any problems with CELs coming up with a new exhaust and removing the 2 cat? Also, any ideas about the downpipe? From what I have seen it's not really 100% possible.
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The 2nd cat is not monitored so you can't get a CEL. You will definitely get a CEL from most high flow cat DPs or catless DPs. I installed a catless DP and got a CEL with 100 miles, the typical P0420. I removed it because it was just too loud.
Some people report some luck with spacers (can lead to a P0430 code) and such but the best way to go is to install a delete-R from Akropovic, it will still make you fail emissions though I believe. |
So I guess I'm SOL with the DP eh? From what i have heard it deletes the code but leaves a pending code.
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Yeah, I think the pending code will still be there, just gets rid of the light.
To be honest it's really not that hard to swap it out once a year. When I installed the DP for the first time it took me about 4-5 hours. When I swapped it back it took just over an hour. Having a new exhaust band clamp (where the DP connects to the rest of the exhaust) really helps out - it's a $12 part. I did it on rhino ramps in my garage. A magnetic socket for the 10mm heat shield bolts would be great too. I forgot, the CAN Tool from Burger will get rid of the CEL too. |
I definitely wouldn't mind swapping it out. How difficult would you say it is? I was planning on getting all this done at a shop since I don't have the proper space or tools to really do it. I can't say I'm experienced with cars this would be my first project. Still trying to learn and decided to start with the exhaust and later move on to the engine.
Will the CAN tool just get rid of the light? |
It's really straight forward, the problem is the tight space you're trying to work in.
There is: 10 bolts for the upper and lower heat shields 3 nuts on the DP to turbo connection 2 nuts on the DP bracket (from under the car) 1 band clamp connecting to the rest of the exhaust 2 O2 sensors need to be removed (use an offset O2 socket) After you do it once you figure out tricks to speed up the process You can do it in a parking lot on a nice day on ramps and a very basic set of tools. 1/4" drive socket wrench 1/4" extension (3") 10 mm magnetic socket (1/4" drive) 13 mm socket (1/4" drive) 10 mm ratchet wrench 13 mm open end wrench 3/8" drive socket wrench 16 mm deep socket (3/8" drive) offset O2 sensor socket (3/8" drive) The thing to be careful of is the studs/nuts on the DP to turbo connection. One of my studs backed out and then seized. It ended up striping the threads on the turbo and I had to retap it. It could have been much worse. https://lh6.googleusercontent.com/-a...o/IMG_4205.jpg Here is the specs on the CAN Tool: http://burgertuning.com/CAN_reader_tool_for_BMW.html If you're planning a tune, then most tuners can tune out the CEL. |
Which cat is the more restrictive one, first or second? I'm also considering a Akrapovic DP and deleting my second cat and perhaps my Bolra resonator. :grin:
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Originally Posted by Scooby Doo
(Post 3862842)
I live in Illinois Awesome, do you know how I can check about the 2nd cat being gone and how legal it is for Illinois? Also have do you have downpipe exhaust? Which state are you from if you don't mind me asking. Thanks
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Originally Posted by Systemlord
(Post 3863002)
Which cat is the more restrictive one, first or second? I'm also considering a Akrapovic DP and deleting my second cat and perhaps my Bolra resonator. :grin:
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Originally Posted by cerenkov
(Post 3862904)
It's really straight forward, the problem is the tight space you're trying to work in.
There is: 10 bolts for the upper and lower heat shields 3 nuts on the DP to turbo connection 2 nuts on the DP bracket (from under the car) 1 band clamp connecting to the rest of the exhaust 2 O2 sensors need to be removed (use an offset O2 socket) After you do it once you figure out tricks to speed up the process You can do it in a parking lot on a nice day on ramps and a very basic set of tools. 1/4" drive socket wrench 1/4" extension (3") 10 mm magnetic socket (1/4" drive) 13 mm socket (1/4" drive) 10 mm ratchet wrench 13 mm open end wrench 3/8" drive socket wrench 16 mm deep socket (3/8" drive) offset O2 sensor socket (3/8" drive) The thing to be careful of is the studs/nuts on the DP to turbo connection. One of my studs backed out and then seized. It ended up striping the threads on the turbo and I had to retap it. It could have been much worse. https://lh6.googleusercontent.com/-a...o/IMG_4205.jpg Here is the specs on the CAN Tool: http://burgertuning.com/CAN_reader_tool_for_BMW.html If you're planning a tune, then most tuners can tune out the CEL. |
Originally Posted by RobMuntean
(Post 3863004)
The DP is more restrictive. You'll get a CEL unless you get a can tool or Delete-R to get rid of it. Otherwise go with no resonator and 2nd cat(not monitored) and won't cause a CEL.
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Originally Posted by Systemlord
(Post 3863072)
What's a Delete-R?
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Sorry, I'm late, but is this a race car? If you don't require every last hp, why bother with a dp? The Mini is not, and never will be, a fast car. Even if you get 300 hp out of it, (which you really can't), you can't effectively put it to the ground.
Spend your money where it will do the most good. Tires, suspension, and driver training. |
As others stated, depends on which state you are in and their emissions inspection process. Here in AZ, they plug a laptop in the OBD port and look for an emissions related code. The only thing they actually inspect is the gas cap.
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Originally Posted by richardsperry
(Post 3864725)
Sorry, I'm late, but is this a race car? If you don't require every last hp, why bother with a dp? The Mini is not, and never will be, a fast car. Even if you get 300 hp out of it, (which you really can't), you can't effectively put it to the ground. Spend your money where it will do the most good. Tires, suspension, and driver training.
lol but in all seriousness you're right. Good suspension, not the crappy stuff, tires, and of course, proper driving technique to make the most of it. |
Originally Posted by richardsperry
(Post 3864725)
Sorry, I'm late, but is this a race car? If you don't require every last hp, why bother with a dp? The Mini is not, and never will be, a fast car. Even if you get 300 hp out of it, (which you really can't), you can't effectively put it to the ground.
Spend your money where it will do the most good. Tires, suspension, and driver training. I also do plan on driver training. I wouldn't say I'm a perfect driver but I can do basics like heel-toe. I want a car I can enjoy since I love driving, but it also needs to be a DD for now. |
You are of course free to do whatever you want. But until you get it tuned,get in intercooler, other boltons, all a downpipe really does is make it loud, make it stink, and causes more work to replace it to pass emissions.
You really want to be faster? Tune the car, install a LSD, and sticky tires. Is a good stat. Traction control is no substitute for actual traction. |
Originally Posted by richardsperry
(Post 3864738)
You are of course free to do whatever you want. But until you get it tuned,get in intercooler, other boltons, all a downpipe really does is make it loud, make it stink, and causes more work to replace it to pass emissions.
You really want to be faster? Tune the car, install a LSD, and sticky tires. Is a good stat. Traction control is no substitute for actual traction. |
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