HEY THERE GUYS, I have a new style ford and Im wondering if anyone had taken off the cats yet?? I've heard the 2 back ones are just noise reductors and you can take them off. Im currently running a dual straights but want it loudeer, I just bought a K&N Cold Air, I noticed it got a little louder but I want it LOUD!!! Any tips please to taking these out will be appreciated.

 

Ok, what year, what engine. No you can not take off the cats, and OBD-II laws states that you must maintain all the factory cats unless your local laws say otherwise, or unless the converter you are using as a replacement has been approved as a two for one replacement. You cannot simply cut the cats off, but there are a number of aftermarket converters that have been approved, but I would still need to know exactly what truck you have to make any recommendations. The two back ones are not noise reducers, they are fully functional converters that aid the front one. GM uses single larger converters, but they break, by making them smaller and splitting them into multiple units, they become much stronger and have a lower incidence of failure.

 

Uh... sure. Pretty expensive noise reducers

 

um i have a 2004 f150 fx4 new bodystyle

 

first its against the law everywhere to remove cats, they have to do with emissions laws, which are federal, and your going to need to do work on your computer to make it not run lean/rich, cuz of the 02 sensor i believe, so its a lot of work and it wont be all that great

 

It really won't gain you any power, little economy gain, and on some applications, it hurts fuel economy. It will make a world of difference where you bring out the tailpipe. If you exit in front of the rear tires, it will be more audible inside the cab. I'm sure its already plenty loud, try rolling down the windows. The cab is designed to be as quiet as possible, which may be defeating what you are trying to do.

 

I never heard of second series of cats, they are probly resonaters. Carefully sawzall them off and slip in some eliminater pipe. Don't rid the cats though, not really much need to.

 

There are no resonators. There are converters. If you have never heard of them, you apparently haven't ever looked at a Ford system. On trucks, excluding the heavy duty models, there are almost always two converters per bank.

If you are looking for more sound, just use a high flow converter as a replacement for the rear cats. Even then, you won't gain much sound. As a mentioned above, you can often gain a lot of sound by where you exit the tailpipes. In front of the rear tires is much louder and more noticeable from inside the cab.

 

Ok first off the rear cats are real functioning converters but are mainly sound dampeners. Thats what they do unfortunately. But I dont think anyone hear asking about removing their cats cares if its illegal or not. The only time that you need to worry about that is if your state requires emissions tests. If not, then gut or remove them completely. It does make a pretty big difference in loudness.

 

If you remove the cats, your CEL will come on. Other than making the truck a bit louder, there is nothing to be gained.

 

Bear River I agree with you, but you're never going to convince these guys. This will go on forever.

 

I had the rear cats removed when i installed my true dual system. I gained about 1mpg and have not thrown a CEL code yet. You will gain some low end power too.If you examine the law carefully it states you have to have a cat system on your vehicle. The loophole is it only requires 1 cat per bank not 2. My system was installed by a professional shop so it must be legal, i would think.

 

i would have to agree with rplatt56

 

NGibbsons55- I totally agree with the others, removing the cats won't gain you much more sound, it will change the sound to a deeper tone but that's about it, on these trucks anyway.

I've had a 91 F150 4.9L and a 98 Ranger in the past. Both trucks I've removed the cats completely. The volume was only somewhat louder but the sound was definetly deeper. You want to try and get some serious sound out of your truck, I would suggest some long tube headers and stick with your current setup along with some high flow cats. That's about as loud as it gets without doing engine mods.

 

I just had true dual exhaust 2.5" pipe all the way back out to the corners of the bumper into two stainless steel 3" tips I bought from Bear River ( those tips are really sweet by the way) and gutted my two back cats and it is one loud sob! I love the way it sounds.