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Discussion Starter · #1 ·
is it possible to install cutouts precat and be able to pass emissions? I know i can tune for the 02 sensor codes but im not sure on the visual inspection. im pretty sure i can move the cats and pass inspection and i didnt see any room to install the cut outs pre cat without moving the cats.
 

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Are you doing it for sound or performance? If for performance, the cats on the NBS flow really well so you can just put them after the cats IMO. Sound, however, is a different story.
 

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In memoriam...
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installing cut-outs before the cat-cons is just asking for headaches come inspection time.

Also, be aware that in many jurisdictions, remote-operated cut-outs (either electric or cable) are illegal as well.
 

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Discussion Starter · #5 ·
im getting the cut outs for sound and performance but am hoping for pre cat based on sound...i heard it would be a lot louder and that the 'straight pipe' sound isnt too good. If i end up having to go post cat, i guess i can get away with only using one cut out so I can sell my other one
 

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im getting the cut outs for sound and performance but am hoping for pre cat based on sound...i heard it would be a lot louder and that the 'straight pipe' sound isnt too good. If i end up having to go post cat, i guess i can get away with only using one cut out so I can sell my other one
What brand cutouts did you get?
 

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Discussion Starter · #8 ·
i got DHM (with flowtechs). I would like some noise at idle which i heard post cat cut outs will NOT provide
 

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Discussion Starter · #10 ·
really? all other read ups said its normal at idle and loud otherwise (but a lot of people have negative posts about the quality of sound even when under throttle)....
 

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I got mine installed post-cat, and its pretty loud at idle and everywhere else in the RPM range.
same here, I love my cutout and it's installed post-cat. I dont know how much louder you can get my but my head hurts after driving around with it open all the time for more than a few weeks. I also have a big cam though and it changes the tone a lot. I think it sounds awesome under full throttle.
 

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Discussion Starter · #13 ·
i called a shop and they said its more hassle than its worth if i were to install pre cat so post cat it is. Brandon, why do you need a second cut out?
 

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I just have one of the Flowtech manual cutouts right now, I havent bought the electric valve yet. I ordered some recently for out 81 Silvy, but I didnt get one for my truck at the time. What size is the one you have?
 

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i called a shop and they said its more hassle than its worth if i were to install pre cat so post cat it is. Brandon, why do you need a second cut out?
sweet, just do it post cat. it will be loud at idle and when you nail it im not a fan of the tone, its loud as hell for sure but it also gets that glasspack sound. that doesnt happen when you are gassing around town. you will like it, trust us.
 

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I CANT SPELL GET OVER IT
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here is my 94 no cats flowmaster cut out closed it is so loud it shakes the camera lens

 

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sweet, just do it post cat. it will be loud at idle and when you nail it im not a fan of the tone, its loud as hell for sure but it also gets that glasspack sound. that doesnt happen when you are gassing around town. you will like it, trust us.
:word: I will see if i can get a video clip of my exhaust when I get home
 

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Clit and Tire Liquifier
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the cats on the NBS flow really well
A VERY common misconception:read:

I dropped 3 tenths by cutting of my cats that had 120K on them, then later on I put some magnaflow high flows on and slowed back down 3 tenths, I moved out of the neighborhood that was bitching about my truck being so loud and cut them back off and dropped 3 tenths again. I also know of a couple other people who have had the same result by cutting their cats off.
 

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A VERY common misconception:read:

I dropped 3 tenths by cutting of my cats that had 120K on them, then later on I put some magnaflow high flows on and slowed back down 3 tenths, I moved out of the neighborhood that was bitching about my truck being so loud and cut them back off and dropped 3 tenths again. I also know of a couple other people who have had the same result by cutting their cats off.
On stock trucks(or ones fairly close to it) or heavily modded ones?
 

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greyZ71
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I just got cutouts post cat on my truck and they are extremely loud!!
 
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