catalytic convertor solution proposed

[expo5.0]

I have been researching what to do about the cats and the o2 sensors. as far as i can discern you can just remove the rear two cats because they won't set off the check engine lights. all you have to do is run a big fat pipe from the 2nd cat on back but still screw the stupid 02 sensors back in so they can still control the mixture going to the engine. anybody know anything that would suggest thats either right or wrong. that would work in theory. but would it work in real life?

 

[Phi 844]

I think that in theory you can just remove the cats and put a straight pipe in place of them. The only problem is that you wont pass any emissions tests. I do think that since the O2 sensor is in front of the cats that it shouldn't be a problem. You'll have to do it your self because unless you know someone at a shop no one will just weld in a straight pipe in place of the cats. So if you can weld there's only on way to find out if it will set off the check engine light and that's to just do it. Let us know what you decide.

 

[expo5.0]

I INTEND TO DO IT UNLESS SOMEONE RESPONDS SAYING IT DOESN'T WORK. IF I TRY IT AND IT DOESN'T WORK IT WILL BE PRETTY EASY TO RETURN IT BACK TO STOCK ANYWAYS. I WANT TO MAKE IT CLEAR THOUGH THAT I WILL BE RETAINING THE FRONT CAT AND PRE-CAT AND THE REAR 02 SENSORS. I BELIEVE THAT EVEN WITHOUT THE CATS BEING THERE THEY WILL STILL BE NECESSARY TO PROPERLY CONTROL THE MIXTURE. I WILL JUST WELD THE PIPE FROM THE BACK OF THE FIRST CAT ON BACK AND RETAIN THE STOCK O2 SENSOR MOUNTS AS PART OF THE PIPE. IF ANYONE HAS TRIED THIS AND IT DIDN'T WORK PLEASE TELL ME.

 

[Phi 844]

Oh, I missunderstood what you meant. Yeah, I don't think that should be a problem, but then again that's me and I never said I knew what I was talking about.

~Andy

 

[Alto]

That's what I did!

I removed my cats about 5 months ago. I had a local shop remove my cats install my flowmaster. I however had then put on flanges so that when we go back to the good `ol USA I remove my staight pipe and install new cat.

I installed new my 2 new 02 Sensors. I don't have any after the cats. I have no light coming on.

I have notice some loss of MPG but I truely believe that is because of the sh*ty gas over here. The price maybe around $0.70 a gallon but the quality is not as good as it is in the states.

Hope it helps!

 

[Ray Lobato]

Why do you want to remove your cats?
What do you believe you will accomplish from doing this.
I'm just curious, since it is prohibited by fedral law to do this.

 

[LOGJOCKY]

Right now i have the rear cat removed and i have a pipe jammed through the front 1. I dont have my engine light on. I also didn't experiance any loss in mileage when i first did it. Right now though i dont have as good ofmilage as I had but this started just recently. I've had the pipe through the cat for 5 months or so.

 

[Boman01]

Here is what i did, i was driving to a freinds one night and noticed my manifolds glowing when i got out. I thought my cat was plugged. so i took it off and guted the pipe. i then put it back on and also removed my muffler and put a cherry bomb in its place, this made for one mean soundin exuast. i have not had and troubles with lights, BUT you will notice a loss in torque. That is why i am gettin ready to put a all new exuast on mine seein that i do alot of trailer towin my demolition derby cars around! so it all depends on the reason you want it off and what you do with your explorer.

 

[mrboyle]

Originally posted by Ray Lobato
Why do you want to remove your cats?
What do you believe you will accomplish from doing this.
I'm just curious, since it is prohibited by fedral law to do this.

Bravo Ray!
I was going to ask the same question, as well as inform everyone that if caught tampering with federally mandated emissions equiptment they can be subject to jail time as well as a minimum of $2500 fine.

expo5.0, why do you think removal of your cats will increase ypur engine performance? Have you ever seen what the inside of a monolithic cat looks like? You can see clear through them and they flow gas stright through with very little restriction.
Also, I can almost guarentee that removal of the rear cat will set the check engine light.

 

[LOGJOCKY]

ive ahd my rear cat off for half a year and my engine light has never come on. when i took off the rear i noticed a slight increase in power( very slight ) and also a little more noice.the m,ilage is a bit better too. I put a pipe through the first 1 and it dropped in tourque a little. I did not loose any milage though, and my light has still never come on.

 

[youl luz]

i have also removed my back 2 cats .. did it about 2 months ago and no there is no o2' s behind the last cats so the computer doesnt even know you've messed w/ it .. now when you take off the front 2 cats you will get a check engine light.. the cure for this is to buy some "mil eliminators " from dallas mustang.. cost about $60 and just plug into the 02's and tell the computer that the front cats are still there..i have mine but havent had time to gut the front cats .. soon i hope..as far as a torque loss... i dont think i would do this mod on a v-6, but on a v-8 its no problem...

 

[jimmiecakes]

OK, I don't want to point fingers and I don't want to start a flame war. This is just a simple statement and it is just my opinion.......

Pollution is a very, very real problem all over the world and particularily in "civilized" countries. It's one of those areas where, if you're not part of the solution, then you must be part of the problem.

Maintaining a vehicles emission controls can be a spendy proposition, I'll agree. But if we bear in mind that we are simply borrowing this planet from our children, it can make the pill a little easier to swallow.

 

[LXTra]

Do you think that your stock cats are the major bottle-neck in your trucks performance right now or just an easy mod? Since your answer will probably be the second of those two why don't you do it right and get a couple of high flow performance type catalysts and weld them in. You'll get 90% of the performance benefit of throwing out the stock ones without the bad karma. Not to mention the fines and hassles if you get busted. Hi-po cats aren't cheap but they're a hell of a lot cheaper than $2,500.

 

[LXTra]

By the way, I'm not "Mr. Green Jeans" or anything. I haven't actually looked at the exhaust on my X yet but when I do I will probably see 4 cats under there and puke on my driveway. Even if you rip out the 4 stock cats and replace them with 2 hi-flow units you should still be able to pass emissions anywhere. If someone ever makes headers for the SOHC V6 I will probably do a full exhaust with performance cats just like my mustang.

 

[expo5.0]

I want to make it clear that I don't intend to remove my cats. Just the rear two, in all likelyhood the truck would still pass emissions testing. i have friends who have tried emissions here in Arizona with 500 hp 350 with no cats and passed. I realize that my truck will probably pollute a little more, but I'm a strong proponent of the theory/fact that it's not the cars that do the polluting but all the time we are forced to spend in them sitting in traffic. If highways were improved slightly and traffic flow increased pollution would decrease a hundred fold more times than if every vehicle was a LEV vehicle. So i guess i might offend people and risk that fine, but i don't feel that i will be bringing any more bad karma unto myself than i already do by simply driving my v8 powered suv. I would, however, like to reiterate that I'm sorry if I offended anyone, I won't be removing all of my cats, and that we should all encourage out tax money to go to better freeways and traffic management. That last part goes double for those of you who were angered by my post.