To tap or not to tap?

[WRXtranceformed]

Yeah I think I got a Denso replacement, which is believe is what they use from the factory. I may need to order another one because I'm thinking the other one is about due to die also.

[NTIman]

Retap and go on with your life. Either way, the proper way to fix it is to retap it or replace the manifold, go ahead and do it, and if you want to go aftermarket one day or soemthing, fine, if not, its fixed.

Also, I wouldn't run without a precat O2 sensor. They're on there for a reason. It can be common for an O2 sensor for strip the threads, I guess due to heat and rust (mostly rust)

[Jeff]

How do you exactly go about retapping it? I have a 2.5in swingvalve for my turbo on the Daytona that is stripped. They are the largest factory option and are like $100 so I need to fix the one I have. Its weird that the 02 sensor is right in the swingvalve...but I guess it works.

[HAULN-SS]

buy a tap and dye set, start the tap in, rotate clockwise as it cuts the new threads (apply some cutting oil or whatever you have laying around). run it all the way through, back it out, done

[Evan]

technically you should go with a thread chaser instead of a tap. A tap will cut more metal out whereas a thread chaser will clean up the threads and take out a minimal amount of metal.

but yeah, usually i just use a tap.

[JustinG]

lee, just look at the pole that you posted up top, that should tell ya what to do

[WRXtranceformed]

Yah no doubt Justin!! I already put in a PM with the guy committing to buy them :lol:

I really shouldn't spend the money, but I've got some remnants in a checking account in VA that I wanted to crush out anyway. Hooray for cashburn!!

[Jeff]

For the record...I know how a freakin tap works. My question is now do I make them threads the same size to re-use a stock o2? I'm thinking a chaser will do little because the threads looks really far gone. If I tap it out to a larger size I will have to find an oversized o2...get me? Deersty...what kind of tap and die set do you have that goes all the way up to those huge sizes? I'm pretty sure something like this would require some sort of extra large specialty tap.

[Ginger]

Jeff, wouldn't a helicoil do the trick for you? You'd probably have to custom order one that large, but there's worse places to work than a dealership for that kind of thing.

[Ginger]

*I just checked Helicoil's site... they make inserts up to 20mm. A Google search told me that 02's can go up to 18mm. So, um, give a nut a whirl on it and you'll find what you need.

[Jeff]

yeah, we have a huge helicoil kit in the basement...I'll check it out on monday. thanks. My thought was just all the heat and expanding woudl mess up helicoils, but I guess that is what they are designed for.

[HAULN-SS]

For the record...I know how a freakin tap works. My question is now do I make them threads the same size to re-use a stock o2? I'm thinking a chaser will do little because the threads looks really far gone. If I tap it out to a larger size I will have to find an oversized o2...get me? Deersty...what kind of tap and die set do you have that goes all the way up to those huge sizes? I'm pretty sure something like this would require some sort of extra large specialty tap.

i have used a 2" dye before - I have access to one actually. I am assuming there is a tap that goes with it somewhere as well.

[D_Eclipse9916]

fwiw, i ran without a o2 sensor for a while. it doesnt hurt your engine. in fact i got better gas mileage that way.

its strange that a cast iron manifold got stripped by a steel sensor, but i guess if it happens a lot on that car then it is certainly possible!

if the wiring fix truely works and has been done then that is actually pretty surprising. A o2 sensor sends oscillating voltage, not something constant, which is why simply using a resistor wont work. I plan on building a o2 simulator with a breadboard and a 555 timer to fix my cel.
edit: i think i misread your wiring solution. n/m. and holy fuck your car has too many damn o2 sensors.

personally id just do the aftermarket headers anyway. easy solution and you're a ricer anyway.

You may have gotten better gas mileage compared to the o2 sesnor being dead and being put into constant open loop mode. You may get close to the same mileage without an o2 sensor, but do you really think that running without a proper o2 is going to allow the engine to compensate fuel trims in closed loop mode properly? You probably wont notice that much of a difference, but the difference is there, the ECU is no longer monitoring so lo and mid fuel trims are going to be a guesstimate on your o2 simulator.

Edit: My vote...do it proper and go ahead get the aftermarket one for more power, as long as its made properly you shouldnt have a problem with a tubular manifold that isnt holding any weight.

You are correct - you can't use an eliminator for the front O2 sensors. The rear O2 sensors have nothing to do with fuel management however - they are only there to measure the emissions after the exhaust has been filtered by the cat. Thus, a car with a bad catalytic converter (like my GL) will throw a CEL if it detects that the converters are not doing their job. Adding an eliminator for the rear O2 will do nothing except fool the computer into thinking that the car is running extra special clean, keeping the CEL off and making the car pass emissions.

Guess I should have specified that I used the eliminator for the REAR O2s :wink:

LOL .... SPECIFY!!! And trust me :wink: ...... I dont run a rear o2 sensor, I know a little more than you give credit for. :lol:

[WRXtranceformed]

Headers are on their way, I'll give you guys an update on how they feel after I get them installed.

Instead of fixing the bung on my stock manifold and trying to sell it, I may take it to a recycling center and see how much they'll give me for the catalytic converters. I may reclaim more money from that considering oem manifolds aren't exactly desireable and shipping them is a PITA.

Also they're a little rusty in some spots I guess from the Cali air ha ha.. any suggestions what I should do to fix it? Is it worth bothering with? I was thinking sand the rust spots down and blast it with some kind of high temp paint or something.

[Ginger]

My guess is to remove as much surface rust as you can (via sanding or something) treat the rust with a killer (like naval jelly; hardware stores usually also sells kits from brand names) and then blast it with a durable high temp paint... though it probably won't last. Some kind of coating would be best, like jet hot, but that's probably more money than you want to spend.

[WRXtranceformed]

Yeah it's honestly not that big of a deal, especially considering I probably wont have the car for a really long time. The paint will at least hopefully help the rust from spreading for a while. Thanks!!

[Evan]

Headers are on their way, I'll give you guys an update on how they feel

Im going to guess they feel a lot like metal. Hot metal when the car is on.


just a guess.

[WRXtranceformed]

Hot metal with a silky ceramic coating and intermittent rough spots of rust?? :lol:

[Ginger]

Are you gonna sleep with it, or put it on your car?

[WRXtranceformed]

Jenn's coming this weekend, so there's no room left in my bed for an exhaust manifold ..