[Danny_6725]

Hey fellas,

I currently have the borla touring catback exhaust and was thinking of deleting the secondary cats.

Have you guys Had any issues with check engine lights or issues with drivability issues without a tune?

Car is currently untuned and I won’t be putting anymore parts until I’m ready to tune.

Just wondering what the community has done. I was thinking of cutting them out but don’t want to do that if I’m gonna run into issues without running.

Thanks!

 

[Karch]

Why would you get rid of them if you aren’t making enough power to warrant a tune, let alone the fact that a good aftermarket tune makes even an otherwise stock car drive so much better?


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[RobF300]

do it when you tune, and at least think of an upper pulley swap. That along with the tune should be a nice 40hp or so boost in power and it will behave exactly like stock ( unless your tuner is trash )

 

[Danny_6725]

Why would you get rid of them if you aren’t making enough power to warrant a tune, let alone the fact that a good aftermarket tune makes even an otherwise stock car drive so much better?


Sent from my iPhone using Tapatalk

Why would you get rid of them if you aren’t making enough power to warrant a tune, let alone the fact that a good aftermarket tune makes even an otherwise stock car drive so much better?


Sent from my iPhone using Tapatalk

Just looking for a tad bit louder exhaust that’s all.

I’m getting a tune but not yet. Once I have all the parts I will be getting the car tuned but no sense in getting the car tuned twice.

I have a list of parts I’m buying.

-zl1 lid
-reinforced brick
-upper & lower pulley
-cam
-intake
-mammo ported tb
-long tubes
-flex fuel
-injectors
-fuel pump
And tune.

My question is:

Is there any issues with removing the secondary cats right now without tuning the car and will that throw any CEL codes?

do it when you tune, and at least think of an upper pulley swap. That along with the tune should be a nice 40hp or so boost in power and it will behave exactly like stock ( unless your tuner is trash )

Just responded above to the reason why I’m not tuning yet.

Still gathering all the other parts

Tunner will either be local tuner that I worked with before on my lq4. Bootleg burton out of ct or slowhawk performance in Massachusetts

Guys I’m referring to the secondary cats. They are unmonitored. There is no sensor there, I think you guys might be confusing my question with removing the primary cats right after the exhaust manifold

These are the ones I’m referring to. There’s no sensor on them

 

[Heavymetals]

You remove anything before a sensor and you will throw a code.

 

[RobF300]

then just wait until you are doing the mods to modify the exhaust. You may be able to get away with some of those 02 sensor spacers but if you still throw a CEL you will be stuck with it and potentially have a car thats just not running right. Keep the car quiet and safe for now

 

[Heavymetals]

Guys I’m referring to the secondary cats. They are unmonitored. There is no sensor there, I think you guys might be confusing my question with removing the primary cats right after the exhaust manifold

As I said, if there isn't a sensor after the cat, then you probably won't throw a code.

 

[RobF300]

you asked, people answered.

take that information and do as you please

 

[Danny_6725]

As I said, if there isn't a sensor after the cat, then you probably won't throw a code.

Yeah no sensor there

 

[PGA2B]

If you want it louder until you do your mods, pull them.

As you stated, your not pulling the primaries. It's when you pull the primary you need to address them. Make sure when you do all your mods the tuner turns off P0420 and P0430 as well as all the secondary O2 codes BEFORE you start and drive the car. Otherwise you will end up with permanent codes for those 2 and possibly the rear O2 codes.

 

[RobF300]

Well I actually deleted the rear cats for the fun of it everything else stock except intake and honestly not much different in sound or loudness the muffler shop told me it is not like deleting them like on a zl1 or corvette for some reason they get louder than the V. Didn’t affect anything at all by the way.

I deleted the rear cats on both my 18 ZL1 and my 18 CTSV. Both gained about the same amount of sound from it. (Very little) it's most notable at startup, and you're here a little extra pop on de-acceleration. The muffler on the CTSV has ever so slightly more restrictive/quieter than the muffler on the ZL1. (Both cut outs open and closed) at wide open throttle CTS-V has a od whoosh type sound where the zl1 has more V8 roar.

 

[Danny_6725]

If you want it louder until you do your mods, pull them.

As you stated, your not pulling the primaries. It's when you pull the primary you need to address them. Make sure when you do all your mods the tuner turns off P0420 and P0430 as well as all the secondary O2 codes BEFORE you start and drive the car. Otherwise you will end up with permanent codes for those 2 and possibly the rear O2 codes.

Thank you man. That’s exactly the information I was trying to get. Hear what the community has done with first hand experience

 

[RobF300]

Thank you man. That’s exactly the information I was trying to get. Hear what the community has done with first hand experience

read the responses I quoted and do a search, you will find removing only the secondary's produces almost no increase in noise

 

[Danny_6725]

Thank you man. That’s exactly the information I was trying to get. Hear what the community has done with first hand experience

read the responses I quoted and do a search, you will find removing only the secondary's produces almost no increase in noise

Yeah I saw, gave it a read. Not sure if it was for a v3 or v2 though. Either way the V2 has that restricted pipe on the driver side that’s sandwiched. Curious to see if it may actually gain some sound given that I have a borla touring exhaust and not the stock one

 

[kittyboy]

I vote your underbody the second cleanest posted in the past couple months! One guy not long ago, swear he must have had it ceramic coated, no exaggeration. Whatever you decide to due with the cats now or later, your fine. If you are just anxious to turn some wrenches waiting for parts, go for it.

 

[Danny_6725]

I vote your underbody the second cleanest posted in the past couple months! One guy not long ago, swear he must have had it ceramic coated, no exaggeration. Whatever you decide to due with the cats now or later, your fine. If you are just anxious to turn some wrenches waiting for parts, go for it.

thanks bud, I’m gonna go for it. I love the borla touring sound but wish it was a tad bit louder at idle and cruise