Kevindisley

Need to know is there anything to look out for when punching out my cat. I have a 2001 F150 with 4.6 the right side cat is plugged. I don't have emissions anymore in the state I live in and was wondering should I punch them both out or just the one. will this set off an O2 sensor issue and if so can I cure that with a non fouler.

Carcrazygts2

Your truck has 4 cats. The first cats are not easily knocked out.

Mike Gross

Smack it with a hammer.

Ccgts2 is correct, you have four cats. Cats are there to recycle unspent fuel in the exhaust. By punching it out, the potential issue is that your o2 sensor is going to read the mixture as rich and the ecu will lean out the mix to compensate. Not good. By only doing one, your only affecting one bank of cylinders, though there are affects to the entire motor. Having one bank work harder than the other isnt ideal, though thats what the stock exhaust does.

Sounds like you still have safety inspections, otherwise you would be cutting them out entirely. I dont know if you can just drop the rear pair without any issues, dropping all four does cause issues as you're removing the o2 sensors, but theres a mod for that.

If you have the funds high flow performance cats and o2 sensors are a great option.

130428

just straight pipe it