F-body manifolds o2 issue
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From: Home of most 3rd gens Van Nuys, CA
Car: 1987 IROC
Engine: Turbo 293ci 4.8l
Transmission: T56
F-body manifolds o2 issue
so im usin a set of exhaust manifolds left over from my old 02 z28 on my 5.3l swap and havin some clearance issues with the o2 sensor on the drivers side. the position of it would make it go into the frame. did you guys plug it and relocate them or what? i can get a pic if you wanna see what im talkin about.
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From: Pepperell, MA
Car: 1987 Trans Am
Engine: LQ9/L92
Transmission: 4L60E
Re: F-body manifolds o2 issue
not that my exhaust is done yet, but i found the same thing when i first installed the manifolds. plug the hole and weld in a bung further down the y-pipe
Joined: Jul 2008
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From: Long Island NY
Car: 84 Z28......99 TA
Engine: Lq9 6.0... Ls1
Transmission: 4L60E X's 2
Axle/Gears: 3.73 on both
Re: F-body manifolds o2 issue
I plugged the bungs and set up the sensors on the ypipe. You will prob need the extensions too. I'll post some pics later this week. It was a pain in the dick to set it up. O2 sensors kept hitting the pan and shift lever. The lt headers i have are really made for a manual setup. Pita lol
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From: Cincinnati, Ohio
Car: '89 GTA
Engine: 5.7L LS1
Transmission: 4L60E
Axle/Gears: 9 bolt 3.27
Re: F-body manifolds o2 issue
Ill try to get you pics, but I put mine right after the manifolds facing the front of the car. Thats where they had the most space and im not worried about them hitting anything.
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Joined: Aug 2006
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From: Ontario, Canada
Car: 1991 Trans Am GTA
Engine: LSX (swapping)
Transmission: 4L60E (swapping)
Axle/Gears: 2.73 Posi 10 Bolt
Re: F-body manifolds o2 issue
I havent put my bungs in yet, but I bought a set of bungs and plugs from Summit for cheap and plan on relocating them onto my y-pipe.
Joined: Dec 1999
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From: WI,USA
Car: 89 FORMULA 350, 91 Z28 Convertible
Engine: ls1, LB9
Transmission: t56, Auto
Axle/Gears: S60/ 3.73
Re: F-body manifolds o2 issue
that's where mine are. both are just below the collector so there is no need for extensions.
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From: Crestline,OH
Car: 1987 Formula 350
Engine: 6.0 boost and smak
Transmission: 4l80e
Axle/Gears: 9bolt 3.27
Re: F-body manifolds o2 issue
yep, relocat... I put mine where they are real easy to get to under the car. just remember to put them midway up at least in the pipe, mosture doesn't run over the sensors...
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Joined: Nov 2001
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From: Canada,Ont
Car: 1987 TransAm Ttop
Engine: 2005 LQ4
Transmission: Ls1 T56
Axle/Gears: 3:54
Re: F-body manifolds o2 issue
is this common that everyone relocates the o2.I havent tried sitting the motor in with the 02 inplace yet.Looks like I better plug the driver side manifold while the motor is still out and buy bungs and extend some wires.
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From: Home of most 3rd gens Van Nuys, CA
Car: 1987 IROC
Engine: Turbo 293ci 4.8l
Transmission: T56
Re: F-body manifolds o2 issue
ebay sells them cheaper. ive bought alot of them before.
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Joined: Nov 2001
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From: Canada,Ont
Car: 1987 TransAm Ttop
Engine: 2005 LQ4
Transmission: Ls1 T56
Axle/Gears: 3:54
Re: F-body manifolds o2 issue
so is it a common fact that both front o2 sensors have to be relocated when using stock fbody manifolds? I thought only the passenger side needed the o2 bung welded in?
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From: Cincinnati, Ohio
Car: '89 GTA
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Re: F-body manifolds o2 issue
When i built my wiring harness i just used the leads from the rear 02's for them.
Re: F-body manifolds o2 issue
HO2 location, halfway down the 45* bend from the collector flange. For best results the HO2s need to be approx the same distance from the cyl heads
Drivers manifold came with a broken off HO2 already installed. I left it in as a free plug for the hole
Cheap HO2 bungs, go to any local parts store and get a pair of spark plug anti-foulers for large plugs (lawnmowers). Cut off the tip and they work like a charm
Drivers manifold came with a broken off HO2 already installed. I left it in as a free plug for the hole
Cheap HO2 bungs, go to any local parts store and get a pair of spark plug anti-foulers for large plugs (lawnmowers). Cut off the tip and they work like a charm
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From: stockton, CA
Car: Camaro RS/SS
Engine: 5.7 LS1
Transmission: 4L60E Transgo shift kit, 3500 stall
Axle/Gears: 4th Gen Rear 3:42
Re: F-body manifolds o2 issue
This is what i did. Sense i had to take my car to the ref after the swap and the factory cats are really close to the manifold. I plugged the factory O2 bung and welded another bung right next to it. its a tight fit but it works like a charm. Been running like this for 5 years without any problem




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Joined: Nov 2001
Posts: 2,266
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From: Canada,Ont
Car: 1987 TransAm Ttop
Engine: 2005 LQ4
Transmission: Ls1 T56
Axle/Gears: 3:54
Re: F-body manifolds o2 issue
wow thats tight lol.surprised it doesnt brake when the motor is revved.what did you do on the passenger side location?
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From: stockton, CA
Car: Camaro RS/SS
Engine: 5.7 LS1
Transmission: 4L60E Transgo shift kit, 3500 stall
Axle/Gears: 4th Gen Rear 3:42
Re: F-body manifolds o2 issue
the motor doesnt really move when you rev it. I think for the passenger side, i just used the same factory o2 bung.
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Joined: Nov 2001
Posts: 2,266
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From: Canada,Ont
Car: 1987 TransAm Ttop
Engine: 2005 LQ4
Transmission: Ls1 T56
Axle/Gears: 3:54
Re: F-body manifolds o2 issue
iirc the pass. o2 is in the y pipe and not on the manifold. a bung has to be welded in just past the collector
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