See title plz Trying to figure if it is possible to maybe put a cat after the y w/ headers? Just throwing out ideas for cat placement other than on the y pipe

 

Technically, in CA, it's illegal to move the cats. But that didn't stop me . I'm sure an exhaust shop could rig something up. Then all you have to do is find a smog shop that doesn't know what to look for when they inspect.

 

We could interpret your question in a couple of different ways:
1) You want to know the California legalities regarding modification
of the cat(s) for emissions testing.
2) You want to know how far you can move the cats before they
become ineffective.

Heck, you may want to know the answer to both 1 and 2 . I'm not in
California, but I've read the same thing Green96Z mentioned - in CA,
part of the emissions inspection is validating stock placement of cats
(and probably number of). As far as #2 goes, yes it's true, the further
away the cats get from the fresh exhaust, the less effective they are,
because cats do their job most effectively with hot exhaust gases.

 

What kind of headers and y-pipe are we talking about here? Long tubes, mid-lengths, shorties?

 

I was talking about LT headers and just any y pipe that would fit, but im trying to figure out if it would be possible to put a cat at the very start of the i pipe, after the y pipe. I have a hard time seeing exhaust temps lowering that much by only moving the cat about two feet down the line. It just seems like a lot of people complain about little problems here and there with cats on a y pipe. If anything, maybe someone could put a couple of cats back to back on the I pipe. Like I was saying I'm just throwing out ideas. Has anyone tried I pipe cats with LT headers? BTW, I am aware that moving the cats is illegal, but that is stupid and makes no since if it still can pass emissions sniffer tests. I can find some one for testing even if the cat is moved. Another reason why I ask is that I would like to put cutouts right after the headers

 

I think putting the cat in the i-pipe is really pushing it. Even putting it at the end of the y-pipe, the cat still will not be nearly as efficient as if it were directly after the header or exhaust manifold.

 

I'd say that if you put them *that* far downstream, they wont do their job
as designed. The cat(s), at a minimum, need to be right after the collectors.

 

Lame...Well guess that idea is out the window...

 

Yeah it sucks doesn't it? heh

 

You could always consider running dual cats in the y-pipe as well. Instead of running a single cat at the end of the y-pipe, run a cat in each of the branches of the y-pipe.

 

Yea . . . like these: http://picasaweb.google.com/calder.c...45096234007794

 

Yep. Unfortunately, Kooks is the only one that offers a catted y-pipe for the LT1 headers.

 

Ill probably, just run cats right off the collectors or in the branches like you where saying 2000gtp. Im not going to put the cut outs right after

the collector either just because of better scavaging/power at a y/i pipe cut out. Not looking to spend the money on kooks tho, anyone know

what kind of cats fit right on the collector, i've seen some posts of people talking about it, but im tired and my eyes hurt lol.

 

You could get the ORY for your headers, then have a shop just weld cats in there.

 

On the passenger side, you can run just about anything, there is plenty of room. The drivers side is a challenge, you have the floorboard, fuel/brake lines, and torque arm in the way. That is where a smaller length cat such as the mini-cat becomes beneficial.