I have the proper funds to finally purchase a custom exhaust (the famous mangaflow setup.)

I just have a very specific question regarding droning and deleting either the 2nd cat, resonator, or both.

My plan was to remove the 2nd cat and keep the resonator with 2.5 inch piping. Or should i remove just the resonator instead? If i hear any drone, during cruising speeds, i might hurt myself...

I am actually turned off by the burbling sound most of the big mufflers make but i think ill be able to deal with it if it looks sweet. any ideas?

 

I can't speak for sound, but you'll have problems with check engine lights and the like if you get rid of a cat.

 

also... is there even a reason to go from 2.3 (stock) to 2.5?

 

really? there isnt an o2 sensor post 2nd cat... i only saw one on the dp

 

i dont think there is an o2 sensor after the 2nd cat...

that said, im running a 3" catback and there is drone.. im actually considering going back in to get a resonator installed.

 

You will NOT have Engine lights by removing the 2nd cat and/or resonator. If loudness is your main concern I would get rid of the 2nd cat while still having a resonator. It shoudl be fairly quiet while freeing up some exaust flow. Since you are going with Magnaflow, check out their resonators. Just find a competent shop that will know the proper placing of the resonator for the best sound reduction and overall exhaust sound.

 

+1 removing the 2nd cat does nothing in terms of causing CEL's.

 

i have EU version Mini, there is no second cat, i replaced the milltek which is only 2.5", there is an obvious improve of performance....

see the old one...

 

agree with above. I have an EU car here and no 2nd cat!

Milltek:

http://i437.photobucket.com/albums/q...0pics/new3.jpg

Only Cat on EU cars :

http://i437.photobucket.com/albums/q...6112008062.jpg

I thought the Flex join was a second cat Futureal33 quickly corrected me!

 

Have the Invidia exhaust here. It doesn't have a provision for the 2nd cat, no CELs thus far. It does have a larger resonator and I do get drone at highway speeds but I think rather than add a cat back in I'll look into replacing the resonator with one of better quality. Magnaflow defiantly makes some good stuff.

 

Well, I'm happy to be corrected if that's the case, I just can't imagine an automaker having an un-monitored catalyst.

 

The only reason I can figure it's there is for added emissions and to quite things down even more. Otherwise it doesn't really do anything.

 

Theres an 02 sensor at the top of the dp and one at the bottom and the cat is inbetween. Where is this 2nd cat you talk of located?

 

It should be noted that federal law states that it is illegal to remove any emission control device. Violators are subject to a $2500 fine even if it is an unmonitored cat. You may not set off any CELs but those who have a tailpipe probe (sniff test) for inspection may want to think twice. If the federal law doesn't stop you. That being said, its your car do as you like. I just want folks to be aware of the law.

 

If you have a NON EU version then....
after the dp... there is another cat followed by a resonator. the welding of the 2nd cat makes it look like an enlarged pipe. Watever you do, dont touch it after a drive. made that mistake and burnt off a few finger hairs...

 

i was thinking of removing both resonator and 2nd cat... but i wanted to add my own aftermarket resonator to properly take advantage of the 2.5 tubing.

from other random forums, people have said that the magnaflow resonators are bad quality(wears out after a year)... any other reputable companies that make solid 20-25 inch resonators?

edit: anyone know the mini s stock resonator size?

 

cheers!

Its wierd that there is that difference. Burnt my hand probably more times than i should have on my exhaust

 

Pillar, where in MD are you? I've got a 2.5" cat back with a resonator and magnaflow muffler on mine. Got it done by Mandrel Bend Solutions in Pasadena for $450. I love it, especially for the price. Let me know if you want to check it out.

 

No 2nd cat or resonator for 50k with no CEL's or failed emission tests.

 

Hmmm... I've heard of that law, so I wonder how all these manufacturers get away with sellin' illegal products? Maybe, as long as the vehicle passes an emissions test, no one cares. Maybe it's considered a "certified" (by whom?) replacement part? Perhaps someone who is more knowledgeable than myself, a vendor or repair tech, can answer the question. I'd love to hear a definitive answer.

I've seen these disclaimers: "Off road use only" "Not legal for use in California"

 

As Ghosthound and lxjose9xl have already stated above, there are no CELs, but definitely drone at highway speeds with the custom set-up. I'm seriously thinking about giving the Stratmosphere system a try. Anyone have some benji's they want to donate to the cause???

 

Haha Lets have a carwash or cookie sale for a fundraiser.

 

 

I recommend keeping the center resonator. You'll have big drone without it. There's no reason to keep the 2nd cat unless you have strict state emissions testing, or you like to snort your exhaust.

 

im keeping everything stock until after the resonator. change to 2.5 inch piping with the magnaflow setup. if its too soft, then i will take it a step up, remove the stock resonator and 2nd cat and get a nice aftermarket resonater. if its too loud... haha yeah right!