[AndreM818]

I want to take out my secondary cats. I have the full stock system on. Will I lose any horsepower or torque?

Thanks

[scalbert]

No, you will be fine.

[**335i**]

Originally Posted by AndreM818

I want to take out my secondary cats. I have the full stock system on. Will I lose any horsepower or torque?

Thanks

if u remove secondary cats is it that u want better sound or what? i see your signature sais "Muffler delete" u deleted both mufflers?

[FVM3]

if you have deleted muffler and take out the 2nd cats, it sounds raspy

[Transport3r]

Are the secondary cats necessary for passing emissions? Will it throw codes without an O2 spacer?

[Penn999]

Originally Posted by joshuo

Are the secondary cats necessary for passing admissions? Will it throw codes without an O2 spacer?

You mean emissions. And usually, yes. It depends on where you live. If you are in Cali, they do emissions testing and its very strict(fines a lot bigger). But in Virginia we only have a visual inspection, no CARB regulations. In states like Tennessee they dont have any visual inspection at all...Just look up your local laws. I have the Active Autowerke exhaust that has no cats, only mufflers and I have no codes at all.

[AndreM818]

Originally Posted by **335i**

if u remove secondary cats is it that u want better sound or what? i see your signature sais "Muffler delete" u deleted both mufflers?

Oh no, I just put my mufflers back and and forgot to change that. But I'm not looking for sound I'm looking for power.

[k726]

Secondary cats will yield no power. Just sound. If you want power you want downpipes!

[Transport3r]

Hah wow, cant believe i said admissions.
Here in Pennsylvania they actually test..
I thought the secondary cats might have just been to be extra environmentally friendly but not required to stay under the legal limit. guess not

Originally Posted by Penn999

You mean emissions. And usually, yes. It depends on where you live. If you are in Cali, they do emissions testing and its very strict(fines a lot bigger). But in Virginia we only have a visual inspection, no CARB regulations. In states like Tennessee they dont have any visual inspection at all...Just look up your local laws. I have the Active Autowerke exhaust that has no cats, only mufflers and I have no codes at all.

[cb1111]

Originally Posted by joshuo

Hah wow, cant believe i said admissions.
Here in Pennsylvania they actually test..
I thought the secondary cats might have just been to be extra environmentally friendly but not required to stay under the legal limit. guess not

If you are in PA then there is a good chance that you'll fail inspection.

[Penn999]

Originally Posted by k726

Secondary cats will yield no power. Just sound. If you want power you want downpipes!

Are you serious? haha come on. Deletion of ANY cats will give you increased hp. It really just comes down to HOW MUCH HP. When you delete cats your exhaust becomes less restrictive and can flow more efficiently. This reduces backpressure which=MORE HORSES and TORQUE. I believe that if you do some more reading that you will find this to be correct. Here I got you a head start...check out turner's website. They go into detail about it.
http://www.google.com/search?hl=en&s...AAAKoEBU_QrwrA

[Penn999]

Originally Posted by cb1111

If you are in PA then there is a good chance that you'll fail inspection.

The only way to pass in a state that requires testing is to pay someone to turn their head and IF you get pulled you say you installed it last week so the police dont go after you buddy that turned his head OR take the time to re-install your stock exhaust.(A weekend project) If you are that worried about it I would just stay legal. If you are willing to take the gamble, look at it like this. Its only one day of out 365 that you need to be able to pass...so one day out of the year plan to swap out the exhaust or find someone cool and drop um an extra $50 bucks.(which I do) Way more cost effective.

[Iwantm3]

how restrictive are our mufflers ? or do I not know wtf am I talking about ? Also what about the parts where the pipes are really squashed ? its a little bit before the mufflers, would getting same thickness pipes provide a better flow ? thanks

[**335i**]

Originally Posted by Penn999

Are you serious? haha come on. Deletion of ANY cats will give you increased hp. It really just comes down to HOW MUCH HP. When you delete cats your exhaust becomes less restrictive and can flow more efficiently. This reduces backpressure which=MORE HORSES and TORQUE. I believe that if you do some more reading that you will find this to be correct. Here I got you a head start...check out turner's website. They go into detail about it.
http://www.google.com/search?hl=en&s...AAAKoEBU_QrwrA

are u saying that if i delete secondary cats and leave all other exhaust like it is no change yet dps how much hp i can gain?

[Iwantm3]

Yo Lithuania do you have a tune ?

[**335i**]

Originally Posted by Iwantm3

Yo Lithuania do you have a tune ?

dont u see in my signature

[k726]

[QUOTE=Penn999;8296034]

Originally Posted by k726

Secondary cats will yield no power. Just sound. If you want power you want downpipes!

Are you serious? haha come on. Deletion of ANY cats will give you increased hp. It really just comes down to HOW MUCH HP. When you delete cats your exhaust becomes less restrictive and can flow more efficiently. This reduces backpressure which=MORE HORSES and TORQUE. I believe that if you do some more reading that you will find this to be correct. Here I got you a head start...check out turner's website. They go into detail about it.
[url]http://www.google.com/search?hl=en

[Penn999]

Originally Posted by Iwantm3

how restrictive are our mufflers ? or do I not know wtf am I talking about ? Also what about the parts where the pipes are really squashed ? its a little bit before the mufflers, would getting same thickness pipes provide a better flow ? thanks

Mufflers are MAINLY there for sound, but deleting the cats will give you the most HP gain. Ideally you want to get an exhaust that is roughly 3inches ALL THEY WAY BACK. I dont know if you are asking about the thickness of the pipe or the spread of the pipe?

[Iwantm3]

Why don't you get it ?

[Penn999]

Originally Posted by **335i**

are u saying that if i delete secondary cats and leave all other exhaust like it is no change yet dps how much hp i can gain?

Refrase your question, I cant uderstand what you are asking? sorry

[Iwantm3]

Originally Posted by Penn999

Mufflers are MAINLY there for sound, but deleting the cats will give you the most HP gain. Ideally you want to get an exhaust that is roughly 3inches ALL THEY WAY BACK. I dont know if you are asking about the thickness of the pipe or the spread of the pipe?

If ill find a good exhaust pic of e92 I'll show you, do you have a pic by any chance ?

[**335i**]

Originally Posted by Penn999

Mufflers are MAINLY there for sound, but deleting the cats will give you the most HP gain. Ideally you want to get an exhaust that is roughly 3inches ALL THEY WAY BACK. I dont know if you are asking about the thickness of the pipe or the spread of the pipe?

so cats can be deleted and mufflers left as it is or no?

Originally Posted by Penn999

Refrase your question, I cant uderstand what you are asking? sorry

i was talking about stock 335 exhaust do i just delete secondary cats and leave mufflers as it is http://img46.imageshack.us/f/oem20exhaust.jpg/