Catalytic converter help

[Karpiel73]

I have an 01' ex sport and the cats are making noise while idleing. Has anyone here replaced them? Or just removed them completely? If so how did you do it and post pictures if you have any.
Thanks!

 

[Fifty150]

It could just be loose heat shields. Check those first. You can always replace them with Magnaflow direct fit cats. Removing them? What about state vehicle inspection?

 

[Karpiel73]

I was actually thinking of taking the last two cats off and leaving the ones that are just below the headers on. Is that legal? I want to put stainless headers on it but leave 2/4 cats on it to save the cost.

 

[my pos mounty]

It would be legal to remove the secondary cats, as far as I know.
Like what was already mentioned, check those heat shields. That is the most likely source of the noise you hear. Its very typical for those shields to break free at the weld point and rattle at idle.

 

[Karpiel73]

It would be legal to remove the secondary cats, as far as I know.
Like what was already mentioned, check those heat shields. That is the most likely source of the noise you hear. Its very typical for those shields to break free at the weld point and rattle at idle.

I'll check out those shields then. Thanks alot guys!

 

[gavin]

I was actually thinking of taking the last two cats off and leaving the ones that are just below the headers on. Is that legal? I want to put stainless headers on it but leave 2/4 cats on it to save the cost.

depends on state requirements for emissions.

On the Federal level? Yes, it would be legal to remove the rear cats.
If you have no local emissions testing, then it would be fine.

but yeah as stated, check the heat shields. I know a weld broke on one of the cat heat shields. I just took a hose clamp and tightened it down; got rid of the annoying rattle.

 

[Karpiel73]

There are no emissions testing in my county. But there is an o2 sensor (I believe) between the two cats in the rear. If I take them out do I just customize a spot for that sensor?

 

[gavin]

There are no emissions testing in my county. But there is an o2 sensor (I believe) between the two cats in the rear. If I take them out do I just customize a spot for that sensor?

you will not need to (and should not) remove the rear o2 sensor.
The ECM detects the differences between the front and rear o2 sensors and adjusts the air/fuel trim accordingly to get them within their threshold.

 

[Fifty150]

I don't know how much you will gain with a cat-delete. If you have a lifted truck, with more space, then you can get really creative with the exhaust. I've always thought that I could delete the secondary cats, run an x-pipe, then glasspacks under the frame rails on each side, and angled exit just in front of the rear tires.

 

[Karpiel73]

I don't know how much you will gain with a cat-delete. If you have a lifted truck, with more space, then you can get really creative with the exhaust. I've always thought that I could delete the secondary cats, run an x-pipe, then glasspacks under the frame rails on each side, and angled exit just in front of the rear tires.

Cats are ridiculously expensive. That's my gain haha. I'm going for a fully stainless exhaust and couldn't believe how much cats are.

 

[gavin]

Cats are ridiculously expensive. That's my gain haha. I'm going for a fully stainless exhaust and couldn't believe how much cats are.

direct-fit OEM replacements are expensive.
The "universals" are not that expensive.

Yeah, $80 or so each is quite a bit when you need 4, but direct-fit replacements are more expensive.

 

[ranger7ltr]

Try > $40 each for universal cats...

And I don't believe local emission laws usurp federal regulations which make removing a catalytic device illegal in any state of the union...

For my cats, I used www.performance-curve.com and got the thunderbolt spincat units[4] for my truck...Those, an x-pipe, and the Magnaflow dual in/dual out muffler works well on my truck...

 

[gavin]

And I don't believe local emission laws usurp federal regulations which make removing a catalytic device illegal in any state of the union...

no, BUT... as long as you don't remove ALL catalytic converters, you are still abiding by federal law with the "emission devices." As long as both banks are going through at least 1 catalytic converter.

although... it may be a gray area.