I have read alot of posts where guys talk about gutting their catalytic converters or cutting them out. Is the catalytic convert not an emission control device that is illegal to modify or remove or is it just me? What's the deal here or are these guys rolling the dice?

 

its illegal.. if your caught.. ur screwed... big money. ha but my old truck had no cats becuz it was mainly an offroad truck and we dont have checks up in northern mn. i dont kno why some guys take off all 4 cats on their fords.. ford has decent flowing exhaust that i would put money on they lose hp with removing them. but they gain a slight more loudness to their exhaust.. personally if i were to take mine off i would put highflow ones on just so that i dont have to worry about the sniffer tests

 

Legally, it is a federal offense to remove the cats on your vehicle. You can be fined heavily if caught. Not only that, removing them does almost nothing for you in terms of HP. The cats that have come out in the last 5-7 years are very efficient and cost almost nothing in HP. You're only legally allowed to replace them after 50,000 miles or if they are faulty but the keyword is replace.... you're not suppose to remove them or "gut" them.

Not only that, but having a car/truck with no cats kinda sucks when you have your windows open and all you can smell is unburned exhaust blowing in your window. Been there, done that, didn't like it.

 

Okay, that's what I thought but I keep hearing of guys messing with theirs....... oh well.

 

i dont know, when i was living in montana people use to always tear off their cats. out in cali, thats another story..lol i agree though, i dont think it will make much of any difference performance wise.

 

Mine got fouled because of an overly rich tune when I initially got my blower. Factory cats were about $1000, so it was off to E-Bay for some Magnaflow high-flows, like $60 apiece.

I wouldn't have bothered replacing them if I didn't need to. I don't think the factory cats are significantly better or worse (performance-wise) than the aftermarket ones.

 

Here's the long version:
http://www.epa.gov/otaq/cert/factshts/catcvrts.pdf