Catalytic removing or gutting

[keithstef]

Has anyone removed or "mod'ed" the catalytic converters on their trucks?

 

After looking at my exhaust I see that it may be posible.

 

The questions that poped up is what will the computer do? Since there is a O2 sensor before and after.

 

I understand the enviorment and legal concerns....

 

If anyone tried this, did torque, power, or MPG change?

[Frank S]

It'll probably be opening the back end up too much and you'll lose low end performance.I'd also imagine that it would cause the post cat O2 sensor to throw some codes.

 

I don't see where it would be overly beneficial to gut it considering the above facts plus keep in mind that it is illegal.If you want to try and gain performance,try a hi flow cat though I doubt you'd notice much of a gain from that either.

[MS3DALE]

I'd also imagine that it would cause the post cat O2 sensor to throw some codes.

Yes,It will more than likely set some DTC's because the O2 sensors need to see a certain amount of backpressure and if you "gut" the converter it will definetly change the backpressure,we've seen it here at the dealership a couple of times and believe me you don't want to have to buy a new converter,lotsa' $$$$$!

[GMCSierra04]

Hi, don't remove your cat or gut it. Yes besides the fact of tampering is a federal law, you will maybe only see 1 or 2 hp difference. The new 3-way catalyst design is very efficent in flowing exhaust gases and cleaning up "dirty" engines that it will be more trouble than its worth. The only benifit I could see is having a badass sounding truck

 

O2 sensors do not read back pressure in the exhaust. Yes it will change the amount of backpressure by taking out the cat but thats another thing. The way the O2 sensor works is that power is sent to the sensor and once they are heated up the amount oxygen that flows by it will change the resistance in the head of it. This information is sent back to the PCM via a AC signal where the computer can then make changes to the A/F ratio. Either the more or less voltage seen by the PCM will deturmine pulse width of the injectors to achieve that desired 14.7:1 A/F ratio.

[silverado3500]

I removed the kats from my obs 3500 454/4L80E, without throwing any DTCs, however, it should be noted that my truck has NO o2 sensors after the cats, only the 1 on each manifold.

 

You will loose a little off of the low end, unless you are towing heavy loads, you won't notice the difference. I'm doing some head work and a moderate cam, so for me, backpressure is less of a consideration, than If you intend the keep the internals stock.

 

Hope this helps.