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Discussion Starter · #1 ·
I dont have thr funds for gettings hfc's thanks to college, but the guy at pfe performance in michigan is willing to cut the cats off and install ss pipes instead, or can i gut the cats out and install a smaller pipe going through the cat to make it look like cats are still on the car for warrenty purpose. And another question i bought my car from a chevy dealership used with extended warrenty only have 47k miles rn. Say i take my car to get warrenty work done and they dont see cats cant i say when i bought it used it didnt have cats but it still is pre certfied and still has coverage when i purchased the car they cant deny me.. thanks guys
 

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The problem with the factory cats is the pipe reduces down to only 1.75" which is a major restriction. The cats them selves are also more restrictive due to doing a better job at reducing emissions. If you gut them it might help a little but you still have that major 1.75" restriction.

Best thing to do is either buy high flow cats, or have a custom pipe bent with flanges connecting the manifold and catback. If you do build that catless pipe it will be obvious that you have made some modifications and clearly dont have cats. With high flow cats it still looks normal.
 

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Charles
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I dont have thr funds for gettings hfc's thanks to college, but the guy at pfe performance in michigan is willing to cut the cats off and install ss pipes instead, or can i gut the cats out and install a smaller pipe going through the cat to make it look like cats are still on the car for warrenty purpose.
Gutting the catalytic converters will almost guarantee worse performance. If you introduce a large open space like that in the exhaust system, the exhaust gasses will lose velocity and it will decrease flow.
And another question i bought my car from a chevy dealership used with extended warrenty only have 47k miles rn. Say i take my car to get warrenty work done and they dont see cats cant i say when i bought it used it didnt have cats but it still is pre certfied and still has coverage when i purchased the car they cant deny me.. thanks guys
LOL wut? If the car is certified used, that means they inspected it and would know if the car was missing the catalytic converters. Even if it wasn't certified, no dealership is going to commit a federal crime by selling a vehicle without federally mandated emissions equipment on it.
 

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Discussion Starter · #4 ·
Ahh i didnt know dealers couldnt sell cars without cats, does powertrain warrenty still get voided even if taking the cats really doesnt effect anything
 

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Ahh i didnt know dealers couldnt sell cars without cats, does powertrain warrenty still get voided even if taking the cats really doesnt effect anything
I dunno. I traded in my heads and cam GTO with Kooks Long Tubes, X pipe, and flowmaster catback at a dealership and they turned around and sold it to a guy. There was no emissions anything on it.
 

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Big D
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Even if it wasn't certified, no dealership is going to commit a federal crime by selling a vehicle without federally mandated emissions equipment on it.
If I am not mistaken it's the disposal of the catalytic converter thats a big EPA thing. In my county there isn't emission testing, but in a few counties that border me you have to go thru emissions yearly to get tags.
 

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Charles
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If I am not mistaken it's the disposal of the catalytic converter thats a big EPA thing. In my county there isn't emission testing, but in a few counties that border me you have to go thru emissions yearly to get tags.
Federal crime, even if your state or the part of the state you live in doesn't have emissions testing. Of course if your state or the area of the state you live in doesn't have emissions testing then nobody would ever know.

42 USC § 7524 - Civil penalties
(a) Violations Any person who violates sections [1] 7522(a)(1), 7522(a)(4), or 7522(a)(5) of this title or any manufacturer or dealer who violates section 7522 (a)(3)(A) of this title shall be subject to a civil penalty of not more than $25,000. Any person other than a manufacturer or dealer who violates section 7522 (a)(3)(A) of this title or any person who violates section 7522 (a)(3)(B) of this title shall be subject to a civil penalty of not more than $2,500. Any such violation with respect to paragraph (1), (3)(A), or (4) of section 7522 (a) of this title shall constitute a separate offense with respect to each motor vehicle or motor vehicle engine. Any such violation with respect to section 7522 (a)(3)(B) of this title shall constitute a separate offense with respect to each part or component. Any person who violates section 7522 (a)(2) of this title shall be subject to a civil penalty of not more than $25,000 per day of violation.
 

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Big D
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I have seen many trucks in my area sold with strait pipes nothing but headers and 3 in pipe and they get sold at the used car lots all the time. I have rarely see a 4x4 with cats on them ever around here.

From reading the law on cats it seems like any tampering with them is illegal even for adding the high flow cats.
 

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Discussion Starter · #9 ·
Well it looks like im going to get vibrant hi flow cats what do you guys think due funds being sorta low well for modding my car i can get each cat for 80$ and is it worth the extra 50$ bucks to get metal casting instead of ceramic honeycomb style? Both are 200cell tho
 

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Personal experience:

Straight pipes crackle a lot. They will be able to tell you have no cats wether you mask them with a hollowed out core or not, because it WILL trigger a check engine light (which is a PITA to disable. I had custom O2 sensors made and that didn't even work).

Anytime you trade in a vehicle, they make you fill out a federally mandated paper on the odometer and thetampering/placement/destruction of the emissions system on your vehicle.

Also, if you do get straight pipes, make sure they do a throrough job on the bends and welds. Apparently, after 3 years of having straight pipes, there is a leak near my flex pipe and my down pipe, which is creating an annoying as hell ticking noise on cold starts (mechanics words).

Also, expect the smell of unfiltered exhaust at every stop.

The sound is great though, and drone doesn't bother me.
 

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If you tell us your current mods and goals (IE-reason for altering/changing cats) we can give you better advice.

If you're looking for more sound, axle backs would be a better choice. If you're looking for a performance boost, a tune would be better.

Help us help you... ;)
 

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Discussion Starter · #12 ·
Arent my mods in my sig? But anyways i have a vector tune, an xpipe and no mufflers in the back, and ive done the airbox mod.. i want louder and better performance bc i cant do anything else to the car without messing with warrenty, ex(headers and rear diff)
 

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As others have said, the connector cuts down to 1.75" and also presents a nearly 90 degree angle (see below). No Bueno! The cast iron manifolds are also very thick and contribute to keeping the exhaust quieter.





Louder + Better performance means ditching the stock manifolds and cats and replacing them with Headers. Unfortunately there is not a lot of cheap ways to go about this. By the time you buy these $80 each cats and then have an exhaust shop chop up and weld in place you are knocking on the doorstep of a set of Pacesetter Long Tubes. If the exhaust shop needs to custom fabricate anything you might drive your overall mod price up above a set of Pacesetters. Ebay has a set for $283.


**EDIT

I saw that the OP does in fact have a tune already.
 

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woot for living in a state that doesnt have testing :) i know people that have bought cars that were open header off of a lot lol
 

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You will gain performance from gutting your cats.
At that point in the exhaust the gases are under so much pressure the open cats will not have much effect.

The SES light you might trigger is a piece of cake to remove if you have a tuner or a friend that could tune it out.

As it was stated before anyone that modifies their cats with either highflow or anything aftermarket is in violation of the law. So dont worry about the law...its a little rediculous and Im surprised it was even brought up.
 

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Discussion Starter · #17 ·
I would grab a set of pacesetters but the car still only have 47k miles and with extended warrenty so i dont wanna void it lol with headers but u guys were great with the suggestions guess im just going with some vibrant hfc's
 

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Discussion Starter · #18 ·
Actually just got a badass deal on some solo cats from a sweet member on these forums
 

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I would grab a set of pacesetters but the car still only have 47k miles and with extended warrenty so i dont wanna void it lol with headers but u guys were great with the suggestions guess im just going with some vibrant hfc's
also headers will not void an entire warrenty.
If they fail your claim if something does happen they have to prove that the headers were the cause of what ever issues you are having.
 
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