[ZakH]

Might be posting this in the wrong forum, my apologies if I did.
But, I was wondering on changing my Cat. I am running a dual Cat-back exhaust from Magnaflow with a Injen Cold air Intake. I was wondering:

1. if there would be any performance gains or change in sound?

2. Would it mess around with my O2 sensor and screw up my cars computer?

also, I was thinking on picking up Headers so I was wondering if that would also give any performance gains? They're in a 4-2-1 set-up.

Thanks for the help, any help will be appreciated.

 

[brian v]

You will definately have to get a tune for that set up as an Exhaust and intake ..

Good Luck shopping for Tunes !

You can let us know how IT sounds Later ...................

 

[Robby]

The only restriction point (and it isn't much) is the turbo inlet/outlet point if you are asking about the 1.4.

Flow modifications prior to or after the turbo would have little effect except at the very top of the rpm scale.....this eighty some odd cubic inch engine doesn't make a lot of 'blow' so the turbo port has to be small to avoid a endless turbo lag.

Short answer, without expensive mods, not much point in making changes to the exaust.
A tune would get more bang for the buck.

If you are asking about the 1.8.......the cat is already larger than needed for the displacement it must handle.
A tuned header, with corresponding tuning, MAY loosen up a few more HP at the top of the rev range.

Rob

 

[CDNCRUZIN]

what about keeping the exhaust stock but replacing the pre-cat with a high-flow cat? one of the guys at the muffler shop was showing me basically the work they would be doing on my exhaust if I wanted a cat-back exhaust and mentioned that I have my cat.. and a pre-cat.. he said that there's restrictions around the pre-cat and that i should change it to a high-flow cat... is this guy just blowing smoke up my a$$ for a few extra bucks?? Their shop came highly recommended to me..

 

[Robby]

The catalyst is not a restriction point on this small engine......a 'high flow' cat just drains your wallet unless changes have been made that create the need for more flow.....primarily being operated at a higher rpm than currently designed.

Rob

 

[CDNCRUZIN]

The catalyst is not a restriction point on this small engine......a 'high flow' cat just drains your wallet unless changes have been made that create the need for more flow.....primarily being operated at a higher rpm than currently designed.

Rob

Thanks Rob! It is tuned (Trifecta) so it's putting out much more power. Still a waste?

 

[Robby]

As I said earlier.....the exaust restriction point (if even measurable) is the inlet and outlet at the turbo........every component of the exaust, from the turbo outlet to the tip of the tailpipe, exceeds the flow at the turbo outlet.

Changing anything beyond the turbo outlet will likely produce no gain (unless sound is what you are looking for) and even that doesn't change much after the turbine beats the soundwaves to death.

Rob