My downpipe includes a cat delete as it is a larger difference in power. It also includes a special O2 bung so as to not set off CEL. Part of the smell is excess fuel which is lessenned when tuned properly.

 

FYI

There are HUGE fines for getting caught with a car with tampered emissions controls..

And there is a huge gain to be had by just going with a better flowing Cat.. From some of the testing, there doesnt seem to be a huge HP difference between using a 3" Cat (catco or other performance) and a Cat Delete.. Also have some respect for the environment, the more we do things like remove a catalytic converter, the more restrictive laws will become about making modifications.

I ran my car with both just to test out my theory.. THERE WAS NO DIFFERENCE in my quarter mile times (Not attributable to driving style that is) I was within a few hundreths.. I think 5-8 hp loss is well worth having the cat.. Plus it quiets down what otherwise would have been a loud exhaust system on my car.

 

I still have my CAT and check out my signature.
I make about 300 at the wheels and I don't have to worry about having a non-street legal vehicle in case the cops decide to check my car out. If you are discovered to have a CAT delete they will confiscate your car and good luck getting it back.

 

I have one. The car definately feels much better especially up top. Honestly though, it stinks and I can't bear the thought of dumping all that garbage into the atmosphere so I'm getting a high flow and putting my cat back on until it arrives.

 

Not at idle. With out a cat your eyes tear at the stop light.

This car smells really bad with out a Cat.

Eric

 

Same with me, without my cat at stoplights it would bother my eyes. I was like if it smells this bad at idle, what is it like at WOT?

 

I could feel the power increase with the delete pipe.

 

One day some manufacturer will get a clue and start selling cats with 10 degree cones on each end, then we'll have cats that flow almost as well as open pipes.

One day...

 

Now which smell would you guys rather have? That awesome, burnt high octane smell, or that rotten-*** egg cat converter smell?

Personally, I'd rather tear up to high octane any day.

 

it's possible that the stock piece is not TOO restrictive, but still...it's a smaller diameter than peoples 3" systems so it makes sense to upgrade it

 

I have stock headers with 2.5 inch downpipe to a 3 inch exhaust with resonator and 3 inch outlet. I want to delete the cat but i am worried that it might make the care boggle down due to insufficient backpressure? would the rrm highflow cat be better?

 

Depending on the state youre in, it is required by emissions to have a cat. They wont pass your state inspection either you can go through the hassel, but not really worth it for such a insignificant gain.

 

i have true 3in from my turbo out and i have no bogging issues at all, taking off at lower rpms is better with a test pipe and the smell isnt that bad. and honestly its like 15 min job if you want to switch it back so why not? or if your that worried about it just spend the extra money and get an electric cutout

 

An 11 year old thread haha. Yea straight 3 inch all the way works great. Hell they even have a 3.5". Probably over 100,000 people running straight 3 inch pipe

 

Wow! This thread is older than my kids.

Keep your stock cat for emissions. Throw it on when you need to pass. When your emissions are done, throw your test pipe back on put the cat away in the basement. Happy motoring.