[Fearl3$$]

Hi guys I am trying to find some infot on doing Decat on the Tiida,
What is the pro's and cons of doing a Decat and freeflow on the Versa/Tiida?

What will be required if you decat?

Some cars fuel milage goes through the roof if you decat?
Is this the case for the Versa/Tiida aswell?

 

[07Versa6MT]

Cats have been free flowing for a while now, and IMO it is a bit of a myth that they choke up engines, at least stock for stock, on most 80's-on motors. They do cause backpressure, they consist of a waffle/mesh grid inside, measureable, but the gain to removing is not really worth it, if at all measureable. You might notice it with an optimal header design. Every header out there for the Versa also comes with a downpipe that replaces the two cats.

Basically, cars without cats stink, IMO not a bad smell, but it chokes you out. Without a cat carbon monoxide will be an issue when starting it in an enclosed area. It may also change the sound a bit, since cats do offer some sound absorbtion or resonance to a degree.

 

[SilverV]

 

[Fearl3$$]

Thank you For the Info. Thus Decat is not a good idea..
hehe, just get a Freeflow box at the back..

 

[rstolz]

Probably the bigger issue is going to be the codes you'll throw from not having them. if you have a catback exhaust like the DC unit, it's a larger diameter than the section of pipe for teh cats, so you get some restriction there that'd be opened up by removing them.

However, there's still a choke point on the exhaust manifold. Right after the collector, the throat of the manifold is choked down for some reason, so to truly get the full effect from opening up the exhaust, you have to do the whole thing, from the manifold back.