Which mods are most likely to cause me to fail an emissions test in Texas?
Keep in mind, we're not talking about California here. Is Texas going to be that difficult or is it really nothing to worry about?

High flow cats? Risky or safe
Headers? Risky or safe

Obviously, any exhaust system will most likely be safe (with cats installed).

 

First of all not all parts of texas even have emissions testing. I live outside houston and we didnt have emissions till last year. So unless you live in a big city like houston, dallas or SA, you only get a visual inspection. That said, you will pass emissions with both the high flow cats, and headers. I am not sure about a G35, but with my mustang with off-road H-pipe I pass emissions even without any cats ( with the appropriate trick of course ) So provided that someone makes the required part for the G, you could even run test pipes and pass emissions in texas.

 

Very true. I go to school in Austin, but my car is registered in Houston so I have to make the trip all the way back to Haris County just so I can get an inspection along with the emissions test.

Whenever I've taken my car to get it inspected before, they always check under the car and under the engine, looking at the cats and the headers. I've always been stock so I haven't had anything to worry about, but I know that the places I've taken it to do visually inspect it quite closely. A cat-back should by no means cause you to fail, but other parts taht actually alter the stock cat configuration could very well cause you to fail.

 

Actually as long as you have cats, you will pass the visual test even if they are aftermarket cats. And headers dont do anything to emissions either. Also I avoid swanky auto shops in sugarland with waiting rooms with free pastries, instead go to lil hole-in-wall looking places. They dont look under the car with the mirrors and stuff and will often let lil things like tint, condensation in headlamps etc slide. But if they do a visual inspection on test pipes then you will fail.