Hollowing cats or removing them. Help.

[98GMCz71]

I have a 98 GMC z71 with a 5.7l 350 vortec that is way too quiet. I plan on removing my cat and putting a different muffler on it for a better sound. Could that in any way affect my engine or mess up anything?

[kstruckcountry]

It shouldn't hurt anything, but it might be best to do the muffler swap first to see how you like the sound with them. If you decide to get rid of them, cut them off and replace with pipe, because even if they're old you can often get money out of them.

[scooby5121]

IT will throw codes from the sensors when the cats are not there...

Engine light comes on saying the oxygen sensors bla bla bla. do you light the light to stay on then you have to leave them alone.

[Badass69]

^{The stock half ton 350 Vortec head pipes are complete garbage being puny 1 7/8" piping. You can buy 2.5" replacement parts or even cheaper just buy the 3/4 and 1 ton headpipes as even with a 350 they are 2 7/8" tubing.}

 

^{Even if you just want the stock manifolds replace the entire pipework from the manifolds to the muffler first.}

 

^{The engine light will come on without the cats but if you haven't already had it done you can get the truck tuned and have the codes ability to report disabled. It's just a catalyst efficieny code set by the lack of difference in O2 content in the exhaust between the forward and rear oxygen sensors.}

[shortyb]

I used to have the same truck. I had the cat cut off and replaced with a pipe and put a new flowmaster on... My service engine light was already on but Im sure It threw a code for some emissions bs. I never had any performance issues with it though. It did make the Flowmaster sound better in my opinion.

[GMstrong]

I know this is kind of old but just figured i give my opinion,I agree with the 1st post,When they are just hollowed imo they sound like S*** run a piece of pipe in them so it still looks like you have them.Good luck.