High flow cats??
 

Well, anyone know where we can get them for our cars and how effective they are?

There universal, you can pick one up off jegs. Then take it down to the shop and have them cut the old one and weld up a new one.

Not very effective maybe 3-4hp.

not really looking for a lot of horsepower from them, but with my Cat-back it should help a little... just want to free up the airflow some more...

Universal. I bought a high flow one for a mitsu mirage off ebay, i cut of the flanges on it and cut the old out out and weld in place. You loss a little of power in the low end, but you gain back in the high end.

By "low end" do you mean RPMs? What would you call low, I usually like to cruise through town at 3000 to 4000 or so RPM where I can romp on it and get the max jump when I want in and out of traffic. Do you mean it's weaker under that area of revs but more powerful in the same sweet spot, or does it only help when I'm running WFO like in a race? I'd rather have the responsive street driving performance.
I've heard the same said about CAIs. I'd like to add both, but one at a time as I scrape up the bucks for it. I'm open th the same sort of advice on those too.

What low end, a highflow cat should up power through out the rpms.

Remember all your doing is taking away the restriction. However expect all that power to come in the highend. Lowend I guess would be to 3k on our cars, it depends on the car. Personally I would pulloff the primary cat (first) that should free up more power and still keep you legal, as well as giving a crazy deep sound.

If your not looking for power then its just not worth puting one in. It makes the exhaust all raspy. Is it wrong for me to be more conserned with the sound then the power? ;)

Its the lower rpm range. it might be different for the 1.8 or 2.0 engine. I was the wimpy 1.6L. You want to free up the exhaust but, you dont want to free it up so much that you lost backpressure and results in power loss. The engine need a little back pressure. Its fine for street performance. I replaced the 2nd one and the sound is nice and deep not raspy.

While you're replacing the cat with a high flow, you might want to just have the exhaust shop make you a custom midpipe with the cat in it, that way you'll have a full header back quality exhaust.