Gotcha. So what are the negatives of removing a cat?
i wouldnt be the best guy to ask, but i'll do the best i can.
first off would be emissions laws. if your vehicle ever gets inspected you could get fined.
second would be environmental impact. i'm no "save the trees, go green" prius-driving environmentalist, but i do understand that my vehicle has the potential to poision the air we all breathe if i start screwing with the emissions system. and i know that the benefits (if there are any at all) of removing the catalytic converters on a near-stock engine are negligible. unless you're building a high performance/race engine those cat's probably arent going to get in the way, and if you're still concerned with it, they make high-flow catalytic converters that still meet emissions standards.
third would be noise ordinance, in my little "barely-on-the-map" city, we used to not have to worry about this, but all the redneck kids at the local high-school with their chopped up exhaust systems got so out of hand, that the police really started cracking down. i even got pulled over for my exhaust and i've got both of my cats and 2 glass packs. (thankfully i didnt get ticketed).
fourth, from the way i understand exhaust (and i may be wrong) you can actually lose some performance if you cut out the cats, and just leave your factory pipe. your factory exhaust system was engineered to perform best WITH the cats in place, so if you decide to remove them, you would probably need to redesign your exhaust system to negate any performance losses, or take advantage of any performance gains
it's your decision but personally i didnt see any need to remove the cats on my truck. i dont really have a problem with anyone who does (except the rednecks in my town who think that their trucks popping like firecrackers in a pvc pipe is the coolest thing ever) as long as they have a properly tuned exhaust to keep it from sounding like crap. remember you're not the only one who has to listen to your truck.
