Primary Cat removal!
03-08-12, 06:06 AM
#1
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Primary Cat removal!
I have an invidia midpipe and catback but wanted to do some modification so went to my exhaust shop. My main request was throatier sound, due to the current raspy sound. The guy immediately saw the cats and asked if I wanted them removed. he was like make sure no "check engine" light will pop after their removal.. and if they are connected directly to the manifold (which he thinks is the case). Any with info about his concerns? Pic below.
03-08-12, 07:36 AM
#2
they are part of your headers (not manifold) and yes you will get a CEL unless you install some extension for your o2 sensors. They should know what these are if they are a shop that works on exhausts.
I want to hear this when your done
Maybe check to see if the SIIKY headers others are using will work on your car. I think they made them for the ISF and ISx50 and its "possible" they may fit or require less modification then chopping your OEM headers.
I want to hear this when your done
Maybe check to see if the SIIKY headers others are using will work on your car. I think they made them for the ISF and ISx50 and its "possible" they may fit or require less modification then chopping your OEM headers.
03-09-12, 07:57 AM
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you will have CEL.. i dont think its a good idea unless you change your o2 sensor because its going to make the engine runs rich or lean ATF ratio,,
why dont you custome make x-pipe?? its the best solution for raspy nois.. but make sure the x-pipe is a real x shape
why dont you custome make x-pipe?? its the best solution for raspy nois.. but make sure the x-pipe is a real x shape
03-09-12, 10:19 AM
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do you call stock exhaust manifolds headers? or you have custom made headers..
to me; header is non oem primary pipes and collector made to replace stock exhaust manifold
the o2 sensors shown in the pic is what is in the mid pipe not in the exhaust manifold. arent there 4banks for o2 sensors??
to me; header is non oem primary pipes and collector made to replace stock exhaust manifold
the o2 sensors shown in the pic is what is in the mid pipe not in the exhaust manifold. arent there 4banks for o2 sensors??
03-09-12, 11:46 AM
#7
Exhaust to me = Headers
Intake to me = manifold
correct those are what was once in the OEM mid section. That was replaced in the pics you see above. I was just referencing the location in the picture not that those are the "primary" o2 sensors. I don't have any pics left of the OEM mid section. Its a U shape that goes into one pipe then another U shape into both mufflers. Mine you will see is 2 pipes all the way back.
Intake to me = manifold
correct those are what was once in the OEM mid section. That was replaced in the pics you see above. I was just referencing the location in the picture not that those are the "primary" o2 sensors. I don't have any pics left of the OEM mid section. Its a U shape that goes into one pipe then another U shape into both mufflers. Mine you will see is 2 pipes all the way back.
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03-09-12, 11:48 AM
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You'll get a CEL. My friend did this on his and got the light right away. It did sound extremely throaty, maybe as far as even too loud. People wouldnt think its a Lexus. More like a V8 muscle car but nicer sound.
03-10-12, 02:46 AM
#9
Exhaust Manifolds = Headers.
Some manufactures have primary and secondary cats. The primary cats usually have pre and post Cat O2 sensors, but certain manufacturers ( Lexus ) make sure both sets of cats are within the pre and post Cat O2 sensors.
If you decate your exhaust manifolds, you will get a CEL unless you can find a simulator or tune your ECU for it.
In your case Rider, you have no secondary cats so O2 sensors will be a problem for you! The cat voltage spike will be instant and will trigger the CEL. Whether that will affect power.... I don't know!
On my M5, it doesn't, it's just an annoying light!
I did this with my M5 as you can see in the attachment, OEM manifold ( headers ) have the primaries built in, I had then decatted. And also had my tune mapped and CEL overriden!
OEM manifolds
Some manufactures have primary and secondary cats. The primary cats usually have pre and post Cat O2 sensors, but certain manufacturers ( Lexus ) make sure both sets of cats are within the pre and post Cat O2 sensors.
If you decate your exhaust manifolds, you will get a CEL unless you can find a simulator or tune your ECU for it.
In your case Rider, you have no secondary cats so O2 sensors will be a problem for you! The cat voltage spike will be instant and will trigger the CEL. Whether that will affect power.... I don't know!
On my M5, it doesn't, it's just an annoying light!
I did this with my M5 as you can see in the attachment, OEM manifold ( headers ) have the primaries built in, I had then decatted. And also had my tune mapped and CEL overriden!
OEM manifolds
Last edited by designo; 06-19-23 at 12:31 PM.
03-10-12, 05:22 AM
#10
^ yes technically they can be called both, when the OP said manifold that is commonly referred to as your intake around me.
Either way you can eliminate the CEL if you do remove them. All you need is these and your CEL light will go away (desingo this will also take care of your CEL in your BMW)
Personally if your going to do something like this I would go aftermarket or have someone make you some headers.
Either way you can eliminate the CEL if you do remove them. All you need is these and your CEL light will go away (desingo this will also take care of your CEL in your BMW)
Personally if your going to do something like this I would go aftermarket or have someone make you some headers.
03-11-12, 10:01 AM
#12
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^ do you think the o2 simulator provided with the sikky header for the ISF will work for our cars?? And what is the piece you posted to eliminate CEL called?
03-11-12, 08:13 PM
#13
^ Yes they should work, for the part I listed above search ebay with this "o2 sensor extension" and you will see a list come up. Different lengths and some are straight. IMO I think the one I posted above will be easier to work with in that tight space but both will do the job.
03-12-12, 02:41 AM
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CEL can be removed by removing the battrie for few min.. it should come if the ECU detects the error again but im still not getting how o2 extention will take care of CEL.. is it by keeping the sensor far from the exhaust gases??
50whp gain is way too much for just headers!!!
50whp gain is way too much for just headers!!!