Cats Vs Off Road Mid Pipe

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Do high flow cars really reduce emissions or should I just go with an off road pipe?
Does it really matter IF you live in a state with a required inspection? An off road pipe would never pass a state inspection.

In a state that would allow a non certified replacement exhaust system the resultant system is never tested to see if it actually works. So even if the replacement high flow cats did increase emissions slightly no one would know.

Most of the makers of high flow cats would want you to believe their product meets or exceeds the OEM. No reason to believe this isn't true for a name brand. Maybe not so true for imported.....

To me you should be asking questions such as:
  • Do you live in a state with a required inspection?
  • Do you care that having an off road pipe may hurt the resale value
  • Is there a possibility that you could move to a state with an inspection in the future? Or maybe where you live now adopt an inspection requirement in the future?
  • Do you as an individual care if your car meets emission standards or not?
IMO the best piece of advice I can give you is to save the old exhaust system. Take care when removing. You don't really know just how hard it is to find a used factory exhaust system until you have to actually find one. In many states the salvage yards are not allowed to re-sell exhaust systems. Or often the salvage yards don't keep cats because the metal inside is simply worth too much.
 
I don't really care so much about passing the inspection I would just switch back to my old mid pipe. I was just wondering if having 2 high flow cats would really be better on gods green earth, then having no cats at all.
 
They are used by people that have to pass emissions and if the OP spends that kind of money and fails.......... Yes they work and pass emissions, at least the branded ones I have seen do.
 
Off road H pipe! You cant deny the sweet sounds of exhaust through straight pipe into some 40 series flowmasters! I got around my emissions with a set of MIL eliminators. The only reason to ever run cats is if your state looks for them being physically on the car.
 
Yes, they work. The modern cat pipes are markedly more efficient than the systems that came on cars 20 years ago. Guys are swapping out 4-cat pipes for the 2 cat pipes and still meeting federal regs.

Personally I prefer cats on a modern vehicle. I can drive behind a 1960's muscle car without cats no problem at all, but for some reason the modern cars just give off fumes I cannot tolerate for long. My state doesn't even do emissions testing anymore, but I prefer to run cats.

Usually most people see the cost difference between the two and just go to the off-road pipe anyway.
 
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Usually with the new cars, it's just an OBD2 check. If your CEL is off, and all the monitors are complete, they send you on your way.

I forget which states actually do a sniffer check. MA used to do it on pre-OBD2 cars yearly, but all of those pretty much rusted away by now so they eliminated it a decade ago. I think CA does smog every 2 years. Unsure what other states do.
 
It's a Bi-annual test in Washington and I'm not worrying about passing it. Anyway is there anyone who knows a good H pipe that fits like a glove? It's a 2003 GT with a 5 speed. Any experience on what fits without any problems?
 
Don't get the summitracing one. I have that and had fitment issues where the h pipes connect to the mufflers. Of course this may have been a one time deal but I also have friends who have had success with the BBK brand.