How to gut your primary cats (Dyno results to come soon)
#151
Lexus Test Driver
iTrader: (10)
Great work..!! And I applaud you on the DIY post & info..
The most important part of reinstalling any O2 or A/F sensor is too never allow the wiring to be wound up on the reinstall.. It creates a problem and eventual failure.
Simple solution is to counter twist the exact amount of turns before threading in, to ensure the wires are perfectly straight once installed..
On the stock sensor and thread it's approx 2 & 3/4 counter clockwise turns from a perfectly straight 4 wires..
Joe Z
The most important part of reinstalling any O2 or A/F sensor is too never allow the wiring to be wound up on the reinstall.. It creates a problem and eventual failure.
Simple solution is to counter twist the exact amount of turns before threading in, to ensure the wires are perfectly straight once installed..
On the stock sensor and thread it's approx 2 & 3/4 counter clockwise turns from a perfectly straight 4 wires..
Joe Z
#152
Driver School Candidate
Join Date: Dec 2014
Location: IL
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Good call! I knew there had to be a connector somewhere....didn't feel like doing a search for it though, haha. Thanks for the info!
#155
Lexus Fanatic
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Join Date: Nov 2004
Location: Under an IS F since 2008
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The plug connectors are not easily accessible per se.. And really only there for when you need to replace the O2 sensor itself..
Joe Z
#157
?
It seems that most people know what they are talking about my question is. If i do delete cats in manifold will that make me fail SMOG. And so people here have mentioned deleting 2ndary cats and mufflers replace with straight pipes and getting gains. Not having alot of money and time,what would be my best option. Im all stock except K&N filter. Thanks for the info.
Ryan
Ryan
#158
Racer
iTrader: (2)
It seems that most people know what they are talking about my question is. If i do delete cats in manifold will that make me fail SMOG. And so people here have mentioned deleting 2ndary cats and mufflers replace with straight pipes and getting gains. Not having alot of money and time,what would be my best option. Im all stock except K&N filter. Thanks for the info.
Ryan
Ryan
From multiple posts, the secondary cats hold things back....along with the crimp in the exhaust and the finally the mufflers. I will be honest the muffler delete might not be for day to day driving.
I'm planning on eventually buying a new/used borla exhaust and calling it a day....but I daily drive my car and dont want to do too much to it, in case some idiot crashes into me...
#159
Yes, deleting the main cats will cause headaches with your emissions testing. If you don't have a lot of cash, don't touch anything in the header.
From multiple posts, the secondary cats hold things back....along with the crimp in the exhaust and the finally the mufflers. I will be honest the muffler delete might not be for day to day driving.
I'm planning on eventually buying a new/used borla exhaust and calling it a day....but I daily drive my car and dont want to do too much to it, in case some idiot crashes into me...
From multiple posts, the secondary cats hold things back....along with the crimp in the exhaust and the finally the mufflers. I will be honest the muffler delete might not be for day to day driving.
I'm planning on eventually buying a new/used borla exhaust and calling it a day....but I daily drive my car and dont want to do too much to it, in case some idiot crashes into me...
#162
Driver School Candidate
Join Date: Sep 2015
Location: Florida
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I'm curious of how these gain compare to aftermarket headers. The oem headers don't look very restrictive. Does any one know the cell counts on primary cats vs secondary cats?
#163
Pole Position
Okay... so I just got a baseline dyno on my completely stock 2012 IS-F Yesterday.
It was DynoJet, put down 348whp.
I was going to do PPE headers first then redyno but I'm VERY tempted to gut my cats and do a STOCK, GUTTED CATS, PPE Header comparison to put this discussion to rest...
Should be pretty accurate since all will be done on the same exact dyno.
I'm just afraid I won't be able to source a another set of factory headers if I chose to go back to stock..
It was DynoJet, put down 348whp.
I was going to do PPE headers first then redyno but I'm VERY tempted to gut my cats and do a STOCK, GUTTED CATS, PPE Header comparison to put this discussion to rest...
Should be pretty accurate since all will be done on the same exact dyno.
I'm just afraid I won't be able to source a another set of factory headers if I chose to go back to stock..
#164
ive been to the track a few times now and have been consistently running between 12.39-12.5 with gutted cats and borla exhaust with upsized tires (275). I'm installing PPE headers within the next week and will be making another trip up to New England drag way. I'm hoping that I'll break into the 12.2's with headers. To my knowledge I don't think someone has done a comparison like this yet. I'm looking forward to the results.
#165
Instructor
iTrader: (5)
ive been to the track a few times now and have been consistently running between 12.39-12.5 with gutted cats and borla exhaust with upsized tires (275). I'm installing PPE headers within the next week and will be making another trip up to New England drag way. I'm hoping that I'll break into the 12.2's with headers. To my knowledge I don't think someone has done a comparison like this yet. I'm looking forward to the results.