I have a 2002 5.4 and it has a Magnaflow 14" under there and I would like it louder. My question is can I just cut the rear cat off and replace it with straight pipe or will that not work and will I get codes. I checked into getting the high flow cats and at $450 after install, that is to much money for just some sound. So if you could can you please help and if you have tried this then let me know what you did and how you like it. Thanks

 

i think cutting off the cats is illegal

Brice

 

I have asked the same question to multiple sources and they all say I wont pass emissions. At least here in Texas anyway. I have a flowmaster 40 series SI/DO with 2 short tundowns before the rear axle it sounds pretty good at certain RPM's but I need more so im thinking of running true duals 2 1/2" pipes too 2 Orig 40's and do the "Lightning Look" with 2 3" stainless tips before the right rear tire. I think it will sound sic. But who knows I think the only way for it to really bark is to run open pipes with headers,cams,etc....

 

Cut the muffler off , not the cats.

 

You will not pass emissions, visual or otherwise..... High flows are worth the $$.

 

Ok how bout here in Ohio I have a 2000 F150 5.4 with a magnaflow.. we have to emissions so what about cutting off my cats?

 

Cutting off your cats is illegal, I know, the fine members of the police have told me so and made me give them my money

 

I know that it is not legal, I just want to cut off the back two and leave the front two on the truck. In Maryland they don't even look under the truck anymore they just plug into the OBD port.

 

well just get some MIL eliminators then and you are set. You can cut them all off if they don't sniff your exhaust for emissions, just as long as you get the MIL eliminators to shut off the rear o2's

 

chop off that muffler. and do a y pipe into duals. or just get true duals

 

Thats why I love MS no emmsion junk. I plan on running high flow cats with my straight pipes. Its not loud enough for me so maybe if I just have one set of high flow cats and then pipes. That should make me happy.

 

That's how they check in Delaware too.
They just plug in to the OBD port and as long as no codes come up your good to go.
Oh and I'm running high flow cats on my truck,,,WOW,,,what a difference!!!!!

Phil

 

Hack your cats off. Your truck won't pass the sniffer test, but if your state is lame like mine and just does an OBD-II emissions test, then you'll pass as long as there is no CEL, even though the only sniffer test you need is your nose...