[335i4u2nv]

Has anyone done this? is there any sound clips? Ive searched but havent found much. Also does ur Check Engine light come on b/c ur O2 sensors now will read to high of heat resistence and throw a code? I know u can get a extension bung but has anyone had this problem? Ive only seen under the car once a couple weeks ago and believe there r 4 cats? no sure thanks for everyones help

[musc]

I think a few guys have done this. Here is a recent thread with some pics from Walked U's car with the resonator deleted and test pipe.

http://www.e90post.com/forums/showthread.php?t=67255

Removing the secondary cats and resonator shouldnt cause any CEL as these are after the 02 sensors. I have heard the sound, and it actually sounds pretty good with the stock mufflers. Maybe WalkedU can chime with a video clip.

[Walked U]

Originally Posted by catm3

I think a few guys have done this. Here is a recent thread with some pics from Walked U's car with the resonator deleted and test pipe.

http://www.e90post.com/forums/showthread.php?t=67255

Removing the secondary cats and resonator shouldnt cause any CEL as these are after the 02 sensors. I have heard the sound, and it actually sounds pretty good with the stock mufflers. Maybe WalkedU can chime with a video clip.

+1,

Ya cats right, you wont throw a CEL.





Heres a clip of the exhaust with no post cats / resonator. Just idle with liek 3k revs. I know I took more but cant find them right now.

Miss that crappy camera. Hahah




fly by



The stock mufflers sound really good. Only reason i got rid of mine was to drop a little weight and get a little bit more flow out of it.

Ive went through a 2.5 inch exhaust system, and now I have a dual 3 inch system. Ill probably put back my stock mufflers on and run an electric cut out because the drone on the 3 inch duals are annoying in 2-2.5k rpm.

[Mikes12985]

that sounds pretty nice for stock mufflers, i like. Mike.

[AW335TT]

Originally Posted by Walked U

+1,

Ya cats right, you wont throw a CEL.





Heres a clip of the exhaust with no post cats / resonator. Just idle with liek 3k revs. I know I took more but cant find them right now.

Miss that crappy camera. Hahah




fly by



The stock mufflers sound really good. Only reason i got rid of mine was to drop a little weight and get a little bit more flow out of it.

Ive went through a 2.5 inch exhaust system, and now I have a dual 3 inch system. Ill probably put back my stock mufflers on and run an electric cut out because the drone on the 3 inch duals are annoying in 2-2.5k rpm.

I was going to do an electric cut out also but the guy told me i have no room. :mad:...I have my cats removed also, but mine sounds diff and a lot louder than the videos you posted...maybe its the camera. Im also running the stock mufflers, but looking to change them soon..just dont know what to put, any ideas??


Where are you getting the electric cut out done??

[Walked U]

Originally Posted by AW335TT

I was going to do an electric cut out also but the guy told me i have no room. :mad:

Dont worry man. Theres always room. Just need to make it.

There was no room for dual 3 inch. But you just have to customize and get rid of some stuff.

[CASHBY]

Originally Posted by Walked U

Dont worry man. Theres always room. Just need to make it.

There was no room for dual 3 inch. But you just have to customize and get rid of some stuff.

3 inch Downpipes would be the shit!

[Walked U]

Originally Posted by CEA 3

3 inch Downpipes would be the shit!

SHHHH hahaha

[335i4u2nv]

wow so the top pic is what they removed? and they fabbed all the rest? or did they just cut out sections and weld in the missing sections?

[Walked U]

Originally Posted by 335i4u2nv

wow so the top pic is what they removed? and they fabbed all the rest? or did they just cut out sections and weld in the missing sections?

Basicly. Just replaced it with 2.5 inch pipes.

I had both pipes divorced, but it was kinda raspy up top.

So I went back to get the H pipe put on.

I have a few more pictures, but i have to find them. Been a long time since my car was close to stock.

[335i4u2nv]

so its better to h pipe it? and im guessing if i explain this all to a shop and bring pics i should be fine?

[judec]

the pure straight pipes will cause drone and ricer sound, especially with the cats deleted and straight flow mufflers applied. I'm not sure it's worth of that +3 HP it adds. So yepp, U should use the H pipe and/or the X pipe, if U want to maintain the cruising comfort and differentiate your fine machine from your neighbour's teenager son's ricer civic...

[sambonator]

Originally Posted by Walked U

...Heres a clip of the exhaust with no post cats / resonator. Just idle with liek 3k revs. I know I took more but cant find them right now....

Are you sure you took the cats out? It sounds like you put the cats in... it purrs

[Cadillac Johnson]

I think that sounds pretty good.

I'm planning on doing a custom dual 2.5in turbo back exhaust using Vibrant metal core race cats with Vibrant straight through mufflers. It shouldn't be too bad and I'm not worried about highway drone. I'm actualy suprised your getting drone at all. My Evo had 3in turbo back exhaust with a testpipe and 3in straight through muffler and I had no highway drone. Adding cats will keep the sound down quite a bit, if it's still too loud I'd add resonators before I changed the design of the exhaust. H-pipes, X-pipes rob power, more than 3hp too, the reason they are quieter is because they hurt flow plain and simple.

[judec]

Vibrant metal core race cats are an excelent choice, they should do the trick and keep your emission tests in order.

How do U handle this?

Aftermarket catalytic converters are only permitted if your vehicle does not have a converter or if a government emissions testing program has determined that the existing converter needs replacement. It is prohibited by law in the United States and Canada to remove a properly functioning factory catalytic converter.

[Walked U]

Originally Posted by Cadillac Johnson

I think that sounds pretty good.

I'm planning on doing a custom dual 2.5in turbo back exhaust using Vibrant metal core race cats with Vibrant straight through mufflers. It shouldn't be too bad and I'm not worried about highway drone. I'm actualy suprised your getting drone at all. My Evo had 3in turbo back exhaust with a testpipe and 3in straight through muffler and I had no highway drone. Adding cats will keep the sound down quite a bit, if it's still too loud I'd add resonators before I changed the design of the exhaust. H-pipes, X-pipes rob power, more than 3hp too, the reason they are quieter is because they hurt flow plain and simple.

I get drone from 2k - 2.5k. Higher than that I dont get any.

I have a resonator also. ( the resonator is 1 canister but dont share flow)

The stock mufflers did a great job in muffling the sound. Also the random crimps in the stock piping helped the noise too.

When i removed the resonator and 2ndary cat there was really no drone in the cabin. It was only when i got aftermarket exhaust systems.

The 3 series cabin is just hard to get rid of drone @ around 2-2.5k, with aftermarket exhaust and get a good gain in hp

[Walked U]

Resonator picture.

[Cadillac Johnson]

Originally Posted by judec

Vibrant metal core race cats are an excelent choice, they should do the trick and keep your emission tests in order.

How do U handle this?

Alright, I looked into this further and it is a federal law that it can only be replaced if the stock cat is damaged, or not functioning properly. It also has to be replaced in the stock location.

Here's the thing, unless your in California where they're rediculous with their testing, the average person working at an emission testing station has no idea where or what kind of cats were on the vehicle stock.

I've never had a problem with it. As long as it has cats, and the tailpipe is clean, and there's no OBDII codes thrown I've passed.

If worse comes to worse, I can put the stock exhaust back on for the testing, which is like every 5 years, or register the car in a county where they have no testing. Since it's never come to that, and I've had nothing but good luck with Vibrant metal cores, I'm not worried about it.

[danielg]

Has anyone done this?

Yes several members on here have, including myself.

is there any sound clips?

See above.

Also does ur Check Engine light come on b/c ur O2 sensors now will read to high of heat resistence and throw a code?

No.

I know u can get a extension bung but has anyone had this problem?

You can get an extension if you want, there's no need to however.

Ive only seen under the car once a couple weeks ago and believe there r 4 cats?

2 @ the downpipe, 2 in the mid section.

[danielg]

Originally Posted by judec

I'm not sure it's worth of that +3 HP it adds. ...

I willing to bet it's more than 3 HP. This is a turbo car we're modding here, and they respond to exhaust mods the most.

[CASHBY]

I just wish someone would come out with 3 inch Downpipes!

Car would make well over 20 HP to the WHEELS! and About the Same TQ!

[DCJAX]

Originally Posted by Cadillac Johnson

Alright, I looked into this further and it is a federal law that it can only be replaced if the stock cat is damaged, or not functioning properly. It also has to be replaced in the stock location.

Here's the thing, unless your in California where they're rediculous with their testing, the average person working at an emission testing station has no idea where or what kind of cats were on the vehicle stock.

I've never had a problem with it. As long as it has cats, and the tailpipe is clean, and there's no OBDII codes thrown I've passed.

If worse comes to worse, I can put the stock exhaust back on for the testing, which is like every 5 years, or register the car in a county where they have no testing. Since it's never come to that, and I've had nothing but good luck with Vibrant metal cores, I'm not worried about it.

Quite a few states don't do the tailpipe test at all these days, they just look in the OBD for emission codes.

I've never heard of anyone being busted for moving/deleting cats. The only time it might be a problem is if the car was impounded and they were trying to find stuff to pin on you.

I deleted the cats on my old car, but doing that extra bit of damage to the enviornment isn't worth it to me these days. A proper race cat should have minimal power losses.

Originally Posted by judec

the pure straight pipes will cause drone and ricer sound, especially with the cats deleted and straight flow mufflers applied. I'm not sure it's worth of that +3 HP it adds. So yepp, U should use the H pipe and/or the X pipe, if U want to maintain the cruising comfort and differentiate your fine machine from your neighbour's teenager son's ricer civic...

In turboed applications an X or H pipe only serves for sound right? I wouldn't imagine it would offer much in the way of TQ gains. (as compared to NA) Hmm, well it actually should show a slight loss of power.