downsides? aside from violating law is there a hinderence in performance? 99 3.0 flex

 

If I remeber right there should be a few cats. The last one I don't think as an o2 sensor, you can take that one out and get a little more sound. Make sure to always run a muffler though or else you won't have enough back pressure and you will lose low end torque.

 

thats what i was thinking. does the cat really hinder performance that much? as in will i notice a big difference without it

 

Doubt it.

 

You'll be fine removing the final cat

 

just the final one?

 

Fine - yes.

Gain anything - no

 

Yep


Didn't say anything about gains lol

 

True, true

lol

 

unless you are boosted see and logan03CO you thought you were done...

You dont have to run any cats at all, but you need the proper tuning to make it run right.

 

i dont know if mine are stuffed up so i guess i'd try removing them if i dont need them. is it legal to remove the fina one, as in will a shop remove it and weld in a piece of pipe? i did that with my donut seal under the pass seat, and it was $20. so i imagine it wouldn't be much

 

Depends on the shop. Its not legal to remove any emissions items but they may.

 

The shop I went to didn't have an issue removing the last one.

 

so what tuning do you speak of to make it run good without cats?

 

Your O2 sensors measure based on the cats being there. Your computer needs to be tuned to know what the new reading will be

 

X3 to tuning. If you want to get rid of them all do that first then get a tuner and send your guy datalogs so he can adjust.

They also have mil eliminators for mustangs they I've heard work on a ranger

 

ok. sounds good to me i'd rathe rnot run cats. i have a jet performance ecm chip now but i think i'd rather go datalog

 

To get it to run worth a damn it's going to run a fair amount of $$$ for hardly anything in return....just saying.

 

thats kinda what i was getting at, is it worth it to take them out. how about just the rear?

 

Taking out the rear cat didn't give me a cel. You should be fine

 

You'll notice everyone is telling you that you will be 'alright' or 'fine' taking out the last one - but nobody is saying you will gain anything by doing it. lol

Just a little observation.


As far as the question about being 'worth it or not'? What's the endgame here? What positive is to be gained? Louder - Is that it?

 

Yeah there's no gain from it just a deeper tone. If you pull your last cat ask the shop if they'll cut you a deal if you let them keep the cat.

I wouldn't pull all of mine out, the last one only at most.

 

i've heard it takes back pressure off the motor. i have no clue about the 3.0 but if it does then i'd imagine it'd help a tad, but if there's no downside i'd remove the rear one, but i wasn't sure how much difference the cat made. i've also been told that they clog up over time and reduce power? not sure how much truth is behind that. but if it is true i'd imagine it's one less thing to worry about, and mine might be clogged and it'd help with clearing things up a bit?

 

The engine was tuned with exhaust so back pressure was already accounted for.

Reducing back pressure wouldn't help.

Cats clogging seem to be a myth as far as I'm concerned, it has to take a lot of miles with dirty exhaust to clog them to the point of having to replace them.

 

gotcha, kinda what i wasd thinking. i found a shop that'll remove the rear cat, and put in a piece of steel pipe. at the very least i'll walk away with a deeper sound.