hello everyone im on my cell phone right now so i dont know if there is a thread about this or not.

my question is would i have a performance gain if i removed my secondary cat? (im only running 1 cat right now)

or

get a high flow cat with a high flow resonator?

which one would have more hp gain?

 

2nd Cat is not necessary at all....just remove it.

Do you have a catted dp?

 

Be careful, depending on where you live it may be illegal to remove the Cat and may fail your car at a state inspection. Assuming the mechanic knows what he is looking at.

 

Its illegal everywhere to run without cats. And you will get some power out of it for the fact that it will flow exhaust better but its not really worth it. But dyno it and find out.

 

no i have a catless dp from rr, and a secondary cat is there for what purposes? lol, restrict more air flow? and sound?

yeah i was probably gonna do that just to make sure if there are any increases or not

yea i know but its all good, i have another year before my inspection is up again

 

Its not illegal everywhere!

I lived in a rural town in Washington state where emissions was not needed. Well, I guess technically it is illegal still but I did it anyways since I did not have to get inspections.

If you are running a catless DP there would really be no point to a cat after your O2 sensors except to help with emissions testing. Otherwise remove it!

 

I believe its just so the car can pass emissions after a cold start.

Pretty useless! If you're already running without your main cat, definitely take out the 2nd one too.

 

Having a catalytic converter is required everywhere in the United States. I live in Florida which has no state inspection and if you are pulled over without a cat on your car it gets impounded. Its a federal requirement just like having a MAF. And this all depends on year of your car but, the MINI falls in the requirement to have them

 

It's a federal requirement to have a MAF?

 

pretty sure cause almost all cars are the world don't have them except the US

 

so i finally decided to cut my secondary cat off. i paid 45 to get it cut off and welded a straight pipe back on.

first i would like to say there is a noticeable power gain. second, it actually didnt get louder until full throttle. also ever since i got my tune, my car has been running lean. removing the cat makes my car feel alot smoother. i had a hesitating issue in 1st and 2nd gears after 3k rpm where the car stutters like huhhuhhuhhuhhuhhuhhuhhuhhuh, but after removing the cat it made it better, instead of constant huhhuhhuhhuh, its more of a huh pause for 1 sec huh pause for 1 sec huh pause for 1 sec huh

well just wanted to say that removing the second cat i guess was a good thing. the only down side was that it smells alot worse now haha oh well

 

huhuhuhuhuuuuuu

Post sound clips!

 

haha ill make a video right now

 

here are some sound clips

first one is normal driving without sports mode

http://www.youtube.com/watch?v=dOORw1yH3OQ

second one is again normal driving without sports mode

http://www.youtube.com/watch?v=V0AFG0-Y9To

and the last one is driving normally with sports mode on

http://www.youtube.com/watch?v=hQn8nqxr2Ck

 

Your info says you have a alta exhuast but in the video it sounds stock?

 

thats cause im not really stepping on it, im only showing what happens when driving slow

 

Ugh, watching those videos and hearing the exhaust it sounds exactly like mine. Mines dual catted but it seems just as loud (although I dont have a tune yet :(). It makes me wish I had a window seat to stare at my car and pass the time daydreaming

 

Come on man.....you know we need exterior video clips.

 

I'm surprised all the green folks haven't complained about this thread yet...

 

OK, I'll do it. Those cats weren't robbing stinkytofu of anything except emissions!

On the other hand, my neighbor probably pollutes more just fueling his old tractor, much less actually running it.

 

thanks! Good man

 

will do today

 

That's because I just saw it!!
With all that is going on with global warming, it is a bit selfish and inconsiderate to everyone that you are now pumping MORE exhaust and emissions into the world. One of the reasons I waited an extra year for Simone was to get a car with lower emissions.

 

Im still pumping out less emissions than most cars, and mines modded .