Let me start off by saying i have a 2004 new body.

I know this has been brought up alot and everything however what do you gain cutting the rear cats off? The person who installed my exhaust setup said that the only thing i would gain was one (1) HP per cat. I know that you will get better sound through the muffler but will the MPG increase as well?

Someone please help me out!!


Greg

 

it will sound alot better. I cut mine off of my 04. what exhaust set up you have?

 

Wont gain any power at all, maybe just slightly more torque to the rear wheels from the less restriction. My truck stock could not break the tires loose from a stand still punch, but when I did it I was able to chirp them with the stock tune still but that was all. Custom tune FTW, now my Toyo 33s can drift out of a parking lot

The cat job is simple, 12" pipes pre-flanged, cut old out, install new with a buddy. The right side will be a major PITA, left side will be a breeze since there isn't a solid welded exhaust right behind it like in the passenger side.

 

Rite now i have flowmaster 40 series SI/DO 3 1/2 tips. What do you have?


I talked to my exhaust guy he said that he wouldnt do it, said i wouldnt gain a thing from doing it except that lousy 1 HP gain, all i really want is better sound just something a lil louder. did any of you 2 gain any more MPG?

 

didnt notice and MPG or power gain. But it will for sure deepen the sound. I have muffler delete and rear cat delete on my truck

 

Taking perfectly good, working cats out of any vehicle is just plain stupid. You gain NOTHING. Repeat, NOTHING.

 

exept sound

 

My truck

http://www.youtube.com/watch?v=BcwqHYC9s8o

Darrens truck, both 04's with rear cat delete(Hope he doesn't mind me posting)

http://www.youtube.com/user/DarrenWS...13/oNNu68iQ7xY

 

Youre right. You gain a crappy, raspy noise that is found on 70s and 80s model trucks that are straight piped. Stupid.

 

its all opinion, I like my truck sounding like a truck. You cant make these trucks sound good with 4 stupid cats in it.

 

Does deleting the rear cats cause any CEL's or anything? Or do the first 2 cats handle the o2 sensors and stuff?

 

you are more likely to lose performance than gain anything. These vehicles aren't like the old days. Ford spends alot of money and time with each part that they utilize.

The cats aren't a restriction on the stock 5.4 3v motor.

If you want a louder truck, get flowmasters...or just run a dumped exhaust.
and it's also illegal

that is why his exhaust guy won't do it. he's looking at a $10,000 fine if ever caught.

 

The only thing I gained was 0.3mpg on my avg econ reading. Otherwise it was the same, but like I said, I was able to chirp the tires better.

 

I live in Canada so its not illegal. The front cats have all the censors and everything. I get comments all the time on how my truck sounds and I like the sound. Its your truck do what you want. Personally I like it, others may not. Its all personal preference

 

I agree. It will just make your exhaust stinky and give the authorities a reason to write you a fat ticket. If you are going to mess with the cats, at least replace them with aftermarket converters.