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Hi Guys,
As the title says if i gutt the primary cats out is getting a tune a must or can I drive the car without a tune for a little while. Anyway to avoid a CEL with the cat removed. Also would gutting the primary cats result in burble and crackle or for that would also need a tune.

Thanks in advance.
 

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You can drive without a tune for a while but it will not be ideal and most certainly need a tune to make the most of it. Don't ignore and definitely invest in a tune.

Gutting alone will not yield burble and pops and bangs. Those are not entirely healthy for your car but you can have some tunes to incorporate that for you, to some degree.

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Agreed, however primary decat is not considered a light mod and therefore to optimise cat deletion, it should really be paired up with a tune, be it evolve or FAMS or whatever.
 

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Ive been thinking to maybe try drilling a 2” or smaller hole in the honeycomb of the cat Instead of gutting them entirely... if velocity is what it needs after all. Or gutting them and then inserting a 2.3” (or whatever perfect diameter) sized pipe that would slide all the way into the cat until it barely reaches the front O2 sensors and then using jd weld epoxy and screws to keep it in place where the rest of the muffler bolts onto the cats...
 

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Is the gas and exhaust smell still really bad if everything else is kept intact besides the gutted primary cats?
 

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I would say the smell is only at start up. If you are going to gut the cats why bother with the extra work? If you can get a clean 2.3" hole through 8" of catalyst kudos to you.
 

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I would say the smell is only at start up. If you are going to gut the cats why bother with the extra work? If you can get a clean 2.3" hole through 8" of catalyst kudos to you.
yea true but the only thing im worried about is leaving any potential small pieces of the catalyst in there but i guess they’d be too small to do any damage IF they get sucked into the headers, right...

someone else mentioned this when someone else talked about completely gutting it... which is kinda hard to believe because the cats are below the Headers and most debris would probably exit out towards exhaust along with the gases...
 
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