Kooks headers on ls3
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Kooks headers on ls3
I was wondering if I need rear o2 extensions on my kooks lt headers Ii bought them off of somebody and he only had the fronts done I can't find just rears anywhere. All I see is fronts for sale everywhere. I have a 2010 base just was wondering
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(And yes, with headers, you need to have the car tuned!!!!)
The reason for this rear 02 delete in the tune, is really a two fold reason, even if you have high flow cats to even think about installing the rear cats to begin with.
Even with high flow cats, the cats are not effective enough as the OEM cats to give the needed differential reading from the front O2 sensors, and since the cats are not as effective at the OEM cats, the rear sensors tend to foul out quickly as well.
As for if you want to add in the rear 02's (and are installing high flow cats to get a differently reading in the first place), then the rear 02's are installed in anti foulers.
The anti foulers gets the rear 02's out of the direct patch, and help to lower their 02 readings.
To sum it up, all the rear 02 sensors are doing is making sure that the cats are doing their job, and the car is looking for less 02 from the front of the cats, to the back of the cats. The front 02 sensors is that the ECM is using for the tune of the car.
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so if i install the headers and just don't plug the rear o2s in will i get a code until i get it tuned cause i want to install them this week but i can't get tuned till next week. so what do i do?
NO, the the rear O2's will be delete in the tune.
(And yes, with headers, you need to have the car tuned!!!!)
The reason for this rear 02 delete in the tune, is really a two fold reason, even if you have high flow cats to even think about installing the rear cats to begin with.
Even with high flow cats, the cats are not effective enough as the OEM cats to give the needed differential reading from the front O2 sensors, and since the cats are not as effective at the OEM cats, the rear sensors tend to foul out quickly as well.
As for if you want to add in the rear 02's (and are installing high flow cats to get a differently reading in the first place), then the rear 02's are installed in anti foulers.
The anti foulers gets the rear 02's out of the direct patch, and help to lower their 02 readings.
To sum it up, all the rear 02 sensors are doing is making sure that the cats are doing their job, and the car is looking for less 02 from the front of the cats, to the back of the cats. The front 02 sensors is that the ECM is using for the tune of the car.
(And yes, with headers, you need to have the car tuned!!!!)
The reason for this rear 02 delete in the tune, is really a two fold reason, even if you have high flow cats to even think about installing the rear cats to begin with.
Even with high flow cats, the cats are not effective enough as the OEM cats to give the needed differential reading from the front O2 sensors, and since the cats are not as effective at the OEM cats, the rear sensors tend to foul out quickly as well.
As for if you want to add in the rear 02's (and are installing high flow cats to get a differently reading in the first place), then the rear 02's are installed in anti foulers.
The anti foulers gets the rear 02's out of the direct patch, and help to lower their 02 readings.
To sum it up, all the rear 02 sensors are doing is making sure that the cats are doing their job, and the car is looking for less 02 from the front of the cats, to the back of the cats. The front 02 sensors is that the ECM is using for the tune of the car.
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I installed high flow cats and connected my rear o2's on my LS2 gto and still got the code. Some people have gotten away with it using those 90 degree adapters posted in this thread and didn't get a code. Some people still did. So it's a 50% shot.
Best way is have them tuned/deleted out in your tune. You can drive the car normally since you do NOT need your rear o2's. Your front o2's is what gives feedback to the ECU about air/fuel.
But definitely do the tune. JUst because you "can" drive the car untuned doesn't mean you should keep driving it like that. Do the tune and get the most out of your new mods.
Btw who's doing your install?
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Why????
High flow cats will only tax you of around 3HP, and keep the car cabin from stinking of unburnt fuel every stop light.
If you can't return the X pipe to get one with High flow cats, then you can pick up high flow cats for around $50 each, and have then installed in the X pipe right after the header collectors.
High flow cats will only tax you of around 3HP, and keep the car cabin from stinking of unburnt fuel every stop light.
If you can't return the X pipe to get one with High flow cats, then you can pick up high flow cats for around $50 each, and have then installed in the X pipe right after the header collectors.
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I am gonna do the install my self but go to cartek in garwood for a tune.
You will get a code either way, whether you plug in your rear o2's or not is what the other guy is saying.
I installed high flow cats and connected my rear o2's on my LS2 gto and still got the code. Some people have gotten away with it using those 90 degree adapters posted in this thread and didn't get a code. Some people still did. So it's a 50% shot.
Best way is have them tuned/deleted out in your tune. You can drive the car normally since you do NOT need your rear o2's. Your front o2's is what gives feedback to the ECU about air/fuel.
But definitely do the tune. JUst because you "can" drive the car untuned doesn't mean you should keep driving it like that. Do the tune and get the most out of your new mods.
Btw who's doing your install?
I installed high flow cats and connected my rear o2's on my LS2 gto and still got the code. Some people have gotten away with it using those 90 degree adapters posted in this thread and didn't get a code. Some people still did. So it's a 50% shot.
Best way is have them tuned/deleted out in your tune. You can drive the car normally since you do NOT need your rear o2's. Your front o2's is what gives feedback to the ECU about air/fuel.
But definitely do the tune. JUst because you "can" drive the car untuned doesn't mean you should keep driving it like that. Do the tune and get the most out of your new mods.
Btw who's doing your install?
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Joined: Aug 2014
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I pick these headers up from someone. I wanted cats but got a really good deal on the headers so I was looking into the cats do they have to cut and weld? or are they bolt on?
Why????
High flow cats will only tax you of around 3HP, and keep the car cabin from stinking of unburnt fuel every stop light.
If you can't return the X pipe to get one with High flow cats, then you can pick up high flow cats for around $50 each, and have then installed in the X pipe right after the header collectors.
High flow cats will only tax you of around 3HP, and keep the car cabin from stinking of unburnt fuel every stop light.
If you can't return the X pipe to get one with High flow cats, then you can pick up high flow cats for around $50 each, and have then installed in the X pipe right after the header collectors.
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