A Serious ? For Serious Answers!!

[dmanmccann]

Hey everybody im a newbie here. My question is for my 99 ranger XLT 4.0. I know there are some very similar questions about this but i'll give it a shot. I want to get an exhaust system put on basically. I want to run a magna flow SI/DO into a 2in pipe branching off into two 3in chrome black tips right in front of the rear passenger tire. Now is it possible to replace the 1st cat with a magnaflow high flow cat and chop off the 2nd cat and rework the o2 sensor to fit behind the first cat?? so basically 1 cat 2 o2 sensors? Ive read about back pressure and all that but i figure running 2in pipe wont hurt anything.

Basically i just want the full potential sound of my 4.0 to come out w/o any restrictive air flow. Headers are in the works but not now.

Thanks for all the posts if there are any....

 

[4LO 4.O]

As long as you keep all the o2 sensor's i dont see why it wouldn't work.
The cats that are installed from the factory are high flow units, so don't expect any horsepower gains from removing it.

 

[Ranger5.0]

im pritty sure you cant do anything with your cats....legaly that is. take it to an exasut shop and ask them what they can do, or will do. Thats prity much what it comes down to. If the are willing, then go for it. The second O2 sensor is there to compare the exaust befor an after the cat. When the cat stops working, it will let the user know

 

[Sunk]

The cats are in there for a reason. I highly doubt a shop would remove them.

 

[Hahnsb2]

A single cat will replace ALL the cats and perform (emissions wise) just as good or better than the factory cats but dont expect more power, just a bit louder,

 

[dmanmccann]

preciate it

Thanks fellers. I should have said the reason also for removing the cats are # (1). they look like shit. #(2) they look like shit and are rusting through..but thanks for the posts..

 

[Jeepman401]

Technically the cats need to be defective to replace them, but nobody is going to give you trouble as long as you replace them with something equivelent, which a high flow cat is

 

[Gabe8810]

im pritty sure you cant do anything with your cats....legaly that is. take it to an exasut shop and ask them what they can do, or will do. Thats prity much what it comes down to. If the are willing, then go for it. The second O2 sensor is there to compare the exaust befor an after the cat. When the cat stops working, it will let the user know

a shop will not remove your cats because if a emissions supivisor or police pul you over for too loud of exhaust they will ether fine you for pulling your cats or if you say the shop pulled them off the shop will be fined.Also if it sets off engie codes for too much flow, you can try and get some mil eliminators

 

[Chic N Stew]

im running straight pipe on my truck right now, but only because i need it to get back and forth to work, doing the exhaust at school with a brand new pipe bending machine, this thing is awesome

 

[85_Ranger4x4]

a shop will not remove your cats because if a emissions supivisor or police pul you over for too loud of exhaust they will ether fine you for pulling your cats or if you say the shop pulled them off the shop will be fined.Also if it sets off engie codes for too much flow, you can try and get some mil eliminators

Shops get inspected for having cats laying around without the paperwork to go with them, it is a $25k fine for the shop that did it and $5k for the tech that did it. Some small shops will do it though, cash only with no receipt, after hours, you keep the cat, and if you get caught (unlikely around here) they have never seen you before. Even those shops are hard to find, the guy almost had a coniption fit when I asked for true duals on my F-150, I had to explain mine had two cats per bank from the factory and they would stay in place with the duals.

Unless you have 02 sensers behind the cats your truck will not know if the cats are indeed there or not, modern cats flow well enough that their resistance will not be noticed much if they are not there. Especially if you are running a high flow and a muffler as well.

 

[rickcdewitt]

go under your truck a block away from the shop with a large sledge hammer and "accidentally" make the cat in question defective.thats what a lot of people do when they want a new high flow cat to go with their cat-back and no trouble with the smog police.also, a one into two muffler will subdue the sound.i have flowmaster 40 series systems with single and dual exit,and the single system is louder.

 

[dmanmccann]

So what ur saying

rickcdewitt...so what ur saying is that a shop will not replace a cat if nothing is wrong..so i make it wrong and they will right?? and a SI/DO muffler will not sound as loud as a SI/SI muffler branching off under the rear passenger tire??? I want to make this clear..

ALSO!!!!!!!!!! everyone knows what their exhaust looks like right? I have 2 o2 sensors before the 1st cat on both sides than 1 o2 after the 2nd cat..So can i AT LEAST take the first cat off and just have 1 cat..or do i need to have both so the check/engine light doesnt come on???

Basically i want my danger ranger to scream....but legally

 

[85_Ranger4x4]

Yeah if you wack with a hammer it they won't be able to tell if it was a hammer or a pothole that did it in provided you don't dent the heck out of it, even then it is damaged and needs to be replaced.

The O2 sensers after the cats tell the computer how effective your cats are at cleaning the exhaust up. If you don't have anything you will get a CEL, depending on how the high flows work out you probably wouldn't get one. If you only have one of the stock ones then there is a good chance you will get a CEL.

Personally I would just leave the stock cats in place and do whatever from there, it would save alot of hassle and money. For a stock application they are not that restrictive. I know it is a completly different truck but my F-150 really opened up just playing with the muffler(s).