What's the difference between a high flow CAT and a Test Pipe?

 

In a few words-DON'T pollute the air with a test pipe on the street! They are illegal (Federal and many states) and really do nothing for overall performance for an otherwise unmodified car. A High Flow CAT costs more and will give you peace of mind (environment). As to the physical difference-look thru the pipe and try to look thru the CAT. We use our CAT as a resonator That's my 2 cents

 

I noticed mine, and the old cat wasn't clogged either, and I passed emmisions with the pipe.

 

A high flow catalyitic converter still has a honeycomb-looking catalyist partially blocking the exhaust pipe, it just flows much better while still keeping the car within emissions regulations.

A "test pipe" is a straight peice of exhaust pipe with flanges on the front and back to bolt in place of a cataylitic converter. It flows better but is not street legal on any vehicle short of special exemptions (like fire department vehicles that drive over brush and the like.)

 

Well, when I bought the car it came with and stil has a ITR 4-2-1 header, and then a straight piece of pipe welded in where the CAT was, and then a resonator, then around a bend, and another resonator, and then finally a Tanabe Medallion Muffler. Should I get a High Flow CAT welded in place of the piece of pipe? Or Should I get a test pipe? Also If I put the High Flow CAT inplace, it will lower the noise level and not throw out as much smoke as usually, and it will have the same amount of flow too. right?

 

Also, where the collector (at least thats what I think it's called) is at. It is the like piece that bends. It has a small hole it in, the size of a quarter. Should I get some exhaust wrap and wrap that hole up?

 

If you want to quiet it down, a cat will help. If the smoke is unburnt hydrocarbons (gas) it will also get rid of that as long as it isn't too rich.

Yes, the leak should be welded up or somehow patched.

 

Yea, I guess I will go with the High Flow cat. I need to get it then, becasue it does smell sorta like unburt gas. And I want to quiet it down a little too.

 

I figure I pretty muhc already have a test pipe on my car, cuz it is just a piece of pipe in place of the CAT. So I think I will get the HIGH FLOW CAT and get it welded onto my exhaust. Also the bendable piece after my header has a small hole in it*from scraping) Should I get that hole patched up, or it doesn't matter?