Don't know anything about this.

I would like to get a high-flow cat and I would like to know if it will pass emissions...

If I get the shell from custommaxima, will that pass emissions?

They don't stick anything in my tail pipe for the check if that helps at all and where would my O2 sensors go and will I get a CEL???

Some advice would be nice...

I just came back from replacing out my high-flow Magnaflow POS cat on my Acura & I'll tell you now its not worth the engine light begin on. Stick with OE replacement cats.

There aren't any sensors on the main cat on 5.5 gens. Swapping it out for a test pipe will be just fine, and won't trigger a SES light. Just make sure you find a way to make it look like a converter so you can pass emissions.

You can use a test pipe in a 5.5 gen without getting an SES light. No problems passing emissions in Texas without a main cat. They check for OBD codes and I have none.

cattman has a fastcat

If you want a true cat and not a test pipe, you can do OE replacement or get a Fastcat from Cattman. The Fastcat apparently flows better than any other true cat. It's $200+ though...

I would go with Fastcat for the OE replacement is also $200+.

While you and I don't have tailpipe testing, some garages may fail you if they don't see a cat so a testpipe. You could go the CustomMaxima cat "shell" route, but then your exhaust will smell bad.

I have a good friend in the garage I go to so I should be ok. I just wanted to make sure there were no sensors I had to worry about so I might do the test pipe thing. thanks for the info.

any gains at all from the test pipe?

a flanged unit from Cattman or WSP!