cat converters

[bluee36e36]

is it worth the trouble or should i just put 2 straight pipes where the cats are now?

[camnipotent]

Are you taking the cats out?

[bitcore]

If you remove the cats, you will not pass the US State emissions tests. May be a good idea for a track-only car but it won't be street legal.

[camnipotent]

He's right. What you can do is get it inspected and then take them out. It adds some rumble to the engine that sounds bad. When I say bad, I mean good. Also, I am not sure where, but I have seen kits that you can put in your car that make it look like you have cats in, but they are hollow. If you're interested, I will look for the place to get them.

[bitcore]

I dont think it matter if it looks like you have cats or not, Don't they hook a tube to your exhaust and test it that way? ...Whole point of emissions testing right?

High flow cats are your best bet if you think your cats are your engine's exhaling chokepoint and wnat to be really streat legal. If you don't care.. Rip the F-ers out

One bootleg way to get "high flow" cats is to take them out, and push a rod in there and get some of the honeycombe out. This can do more harm than good if you dont get the excess out or it dosent break apart really well. Does the trick if you want to remove the cat, but not want to spend money putting new piping in.

[camnipotent]

I am assuming the fake cats are for when your emissions test is somewhat 'shady' and they check to see if you have them in. Another way: It's not what you know, it's who you know....that means if you know someone who works at a shop that is certified to inspect vehicles you couold just get them to check it for you....

[schilke]

There isn't a standard US emissions spec. My state only requires emissions testing in certain counties. I don't happen to be in a county that requires any mechanical inspection or emissions test, and I keep getting a Catalyst Efficiency Below Threshold code.

I am considering removing the cats as well, but...

What could you do to fool the O2 sensor? If you remove the cats with pipes, will you also need to do something to keep the CHECK ENGINE light off?

[Kevin325i]

Isn't the 02 sensor on the manifold before the cats, removing the cats should have no effect on your sensor readings. It will just be crazy loud.

My $0.02 = high flow cat. It eliminates the headache of having to put them in later should your state add emissions testing and if you sell it across state lines.

Kevin

[bitcore]

Originally posted by Kevin325i@Apr 20 2004, 05:48 PM
Isn't the 02 sensor on the manifold before the cats, removing the cats should have no effect on your sensor readings. It will just be crazy loud.

Yes, O2 is before the cats. I've replaced it twice. (I keep burning them :lol

The cats only do some minor noise reduction, so I wouldn't say crazy loud. Noise reduction is not their purpouse, but a side effect of how they work. Mufflers are obviously what reduces the noise. (think: fart cannons on ricers... Eww)

[Kevin325i]

Originally posted by bitcore@Apr 20 2004, 04:12 PM
The cats only do some minor noise reduction, so I wouldn't say crazy loud. Noise reduction is not their purpouse, but a side effect of how they work. Mufflers are obviously what reduces the noise. (think: fart cannons on ricers... Eww)

Ah yes, that's what I get for jumping between the tread on cats and the thread on mufflers. :lol:

Kevin

[camnipotent]

cat means cataytic which means catalyst. It is there to provide a solid medium for CO3 chemical reactions to occur. That's what you know when you major in Biochemistry......