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Headers and Tune Install and Emissions questions

Lcain_s550

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Hello all. I'll be the first to say I'm not the most informed about my car lol. With that being said I need some help. So I'm about to pull the trigger on Kooks LT headers 1 7/8 catted. My main concern is being able to pass emission since the car is my daily driver. Would the GREEN catted headers be my best bet? Also for tuning, is there a "preferred" handheld tuner for the specific car mods I have (basic bolt on (roush intake, ford racing x-pipe, roush AB)) or your own personal preference (handheld or shop)? How does the tuning process work after getting the headers installed for instance clearing codes? I live in TN so they plug into the OBD to read. If I could just get a detailed process of what to do after the headers are installed to pass emissions easily, that would be great! Sorry if that was confusing as I am very confused and just want a loud "legal" car! Thanks for your time and help-Rookie
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Zelek

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Hello all. I'll be the first to say I'm not the most informed about my car lol. With that being said I need some help. So I'm about to pull the trigger on Kooks LT headers 1 7/8 catted. My main concern is being able to pass emission since the car is my daily driver. Would the GREEN catted headers be my best bet? Also for tuning, is there a "preferred" handheld tuner for the specific car mods I have (basic bolt on (roush intake, ford racing x-pipe, roush AB)) or your own personal preference (handheld or shop)? How does the tuning process work after getting the headers installed for instance clearing codes? I live in TN so they plug into the OBD to read. If I could just get a detailed process of what to do after the headers are installed to pass emissions easily, that would be great! Sorry if that was confusing as I am very confused and just want a loud "legal" car! Thanks for your time and help-Rookie
I just bought an Ngauge and Lund tune and I am familiar with this so I can chime in. The tuner will need to make sure you have a tune that has the sensors on or you will fail the inspection immediately for the evap sensors never showing "Ready". They will fail immediately on the OBDII test. The other option is to have two separate tunes, one with them on and one without and just flash it when you go to get an inspection then flash back to your main tune, but that can be a pain.

What I'm hoping for is a tune that will leave the sensors on and still not throw the CEL with the change in flow. I'll trust their word if it can be done, but if I throw a CEL after that, I will ask for a tune with the sensors off.

If you have a visual inspection, the cats should be fine in the connector pipes. You don't necessarily have to go with the green cats either. I have ARH 1-7/8" Longtubes with cats waiting to go on. Just make sure you address that first part with your tuner and you'll be gold. Don't mess with O2 sensor tricks with defoulers. They don't work most of the time. If the tuner is good, he should be able to find you a solution just for this.

Hope this helps.
 
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Lcain_s550

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I just bought an Ngauge and Lund tune and I am familiar with this so I can chime in. The tuner will need to make sure you have a tune that has the sensors on or you will fail the inspection immediately for the evap sensors never showing "Ready". They will fail immediately on the OBDII test. The other option is to have two separate tunes, one with them on and one without and just flash it when you go to get an inspection then flash back to your main tune, but that can be a pain.

What I'm hoping for is a tune that will leave the sensors on and still not throw the CEL with the change in flow. I'll trust their word if it can be done, but if I throw a CEL after that, I will ask for a tune with the sensors off.

If you have a visual inspection, the cats should be fine in the connector pipes. You don't necessarily have to go with the green cats either. I have ARH 1-7/8" Longtubes with cats waiting to go on. Just make sure you address that first part with your tuner and you'll be gold. Don't mess with O2 sensor tricks with defoulers. They don't work most of the time. If the tuner is good, he should be able to find you a solution just for this.

Hope this helps.
Appreciate this a ton. Will definitely get a hold of some reputable tuners around here. Thanks again!
 

Weasel1

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My 2012 GT500 had catted longtubes and a tune from VMP. I lived in Franklin and had the same Davidson county emissions test. Mine passed three years in a row no problem. They even looked under the car with mirrors to check for cats.
 

Grimace427

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The tuner will need to make sure you have a tune that has the sensors on or you will fail the inspection immediately for the evap sensors never showing "Ready". They will fail immediately on the OBDII test. The other option is to have two separate tunes, one with them on and one without and just flash it when you go to get an inspection then flash back to your main tune, but that can be a pain.


Just to clarify.

Top should read rear O2 sensors.


Second highlight; every time you reflash the PCM you clear the readiness tests necessary for passing emissions. You will need to complete the specific drive cycles in order to set all the readiness tests before passing emissions and this can be difficult even with a completely stock car. A car with headers is damn near impossible to set these tests without cheats like non-foulers and even those are not 100% reliable.
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