subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

i was told by the techs i work with, that i'll get a cel if i attempt to run no cat. i have found this to not be true. finished my ---- up tonight, ebay downpipe, steel flange, 6.5ft of 3" exhaust with some whitey bends and lack of actual bends, ending in a thrush turbo. sounds awesome for an awesome sounding car in the first place, but thats not the point. i need to know if i'll run into any issues

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

how would your car know you have a cat

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

He you don't consider that get arrested by cops with no cat is an issue. There is no issue ;)

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

I dont think you will have any issues. Maybe cause a cell but you can buy a cell fixer for the rear o2 off of ebay and have a bung welded in.

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

if its OBD-I and only has 1 O2 sensor, then its pretty much impossible to throw a CEL cause of it... if its OBD-II, then theres a second (rear) O2 sensor, specifically to see if its effectively running "leaner" AFTER the cat, basically voltages shouldnt be the same before/after the cat... there are ways to "simulate" a rear O2 8) if ya gotta pass a OBD-II test.

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

it will come up with a cel. once you clear it, it alwase comes back. ask me how i know this.

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

What all OBDII vehicles are looking for with the pre and post o2 is oxygen storage.When your car runs the readiness monitor for the converter they run the car lean then rich and look for a lag time between the front and rear o2.A working converter will have stored oxygen during the lean cycle and can use it to burn the unburnt fuel during the rich cycle.Also, all OBDII codes are 2 trip logic.If the vehicle runs the monitor for converter for instance,the 1st time it fails it sets a pending code.If it fails the same thing on the next consecutive drive cycle then the pending code matures and you get a MIL light.The only monitor that is one trip logic is a type "A" missfire which will cause the MIL to flash and sets on the 1st failure.
Theoretically you should get a MIL with no converter.
Mark

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

Donald has some o2 simulators as he said their big sellers among suby guys.

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

i took from turbo outlet to muffler off, there is only one o2, i think theres one in the uppipe but i dont remember. ill find out monday. anyways, i ripped on it for a good hour, no cel, unless it's a silent one.

it was started on and off about 4 times. moving to finish exhaust, at the gas station, at my friends, and getting pulled over for running a red light, which was yellow when i was under it. turned yellow on the stop line, fuckers.

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

their its a temp probe in the up pipe on WRX's no 02. Their should be a 02 and a AF sensor on the car stock I think either way ur wasting ur time :X

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

how am i wasting my time?

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

It a WRX right :3

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

thats what you think

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

ull give up when ---- starts to break and it sucks to drive ;) I hate hearing faggots all day at work with WRX/STI's with exhaust driving threw the lot >:(

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

Well I think you will be fine

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

If it does throw one just go to the nearest autoparts store and buy one of the 99cent spark plug extender things and weld it on the bung it works for all the corvette 350z and s2000 guys

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

just get a spark plug de-fouler from autozone and drill it out.... you will be fine.... evo dudes go through the same thing

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

i ran a equal length alphawerks header, catless up-pipe, catless 3" down-pipe, 3" turbo xs cat back, CAI, a rfl bov, and a turbo xs MBC set to the nog setting (18psi). i never got a CEL for any of it. Have you checked out www.nasioc.com or www.clubwrx.com yet?

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

there are two o2 sensors.

up pipe, and one in the midpipe somewhere around teh cat.

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

its in the second downpipe section where it brackets to the trans

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

it wont always throw a cel, but chances are it will. we have a few customers running no cat on their MS3's and havent got a cel.

if you get a cel and need to pass emmisions clear the code and pray

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

it has a 02 sensor after the kat and one before.. so ya taht obd2 ---- is getting too smart :'(

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

You WILL get a secondary O2 cel.
Those ebay adapter/resistor will not clear it on a SUE-BE, I remember reading some homemade ---- online that you will need a resistor and a MFD Cap to get rid of it . JUst look on line I sure there are tons of info.

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

it's not the resistor mod that works for the o2. it's the fact that too much exhaust heat is hitting the sensor, causing it to read fucked. sparkplug arrestors move it away from the heat, letting it work in cooler temps, accurately.

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

wrong as well, to check the operation of the cat the ECu alters your air fuel while cruising and expects a certain AFR after the cat. if it doesnt see these conditions it thinks the cat is fucked.

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

oh you're so right, moving the o2 sensor out of direct exhaust flow is useless, that's why thousands of turbo scooby owners do the said $5 cel fix mod.

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

like i said in my earlier post, you arent garunteed to get a cel, certain ecu's are more sensative than others but all OBD2b and later emission controls have this feature. if you were to get a cel because of no cat that is why

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

You guys are making this ---- way too complicated lol. I have an Evo and WRX and all I have is the auto parts store spark plug anti-foulers on the rear o2 sensors to move them out of the exhaust stream. No cels and no cats. ;) The rear sensor looks for a voltage difference as compared to the front one, so as long as it's out of the main exhaust stream you're ok. No, it doesn't really ---- with afr's during cruise or full throttle, but then again WRX's are pig rich from the factory. The one in the up-pipe you're thinking about is an egt probe. If you haven't done an up-pipe yet I highly recommend it, especially if you think the turbo-back pipework made a difference...plus there's another highly restrictive cat in the up-pipe section. ;D

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

cats are for girls, SES lights +1

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

ive got a chance at an sti uppipe here sometime in the future, if not ill ebay it and resize the tubing on it.

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

As long as the STi pipe has no cats and is a decent size then I'd say go for it. I have a solid thick walled Agency Power piece on mine, the only bitch was having to loosen all the turbo mounts to get all the gaskets to seal properly. I also have to unbolt the motor mounts and jack the motor up a hair for extra clearance, but it was well worth the extra flow compared to that stock 1.5" pipe lol.

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

got my cel this morning coming to work. went to vatozone for lunch, got 2 sparkplug anti foulers. drilled one out to 13mm, threaded the o2 into it, threaded the assy into a un-drilled anti fouler, threaded the ---- into the o2 bung, plugged in the select monitor, cleared my codes, found out that i can adjust things via the selectmonitor, but didnt cause i wasn't sure how it was gonna work. no cel, ill find out in a day or two if it comes back.

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

LOL...My SES light has been on since we turbocharged my car back in August. I have no cat and one of my 02 sensors unplugged...The light will go off EVVVVVERY now an again, but in a few minutes time it's back again.

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

mine never goes off unless i reset the computer lol

no rear o2s :(

i love increasing my carbon footprint in anyway i can

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

Once the anti-fouler is on there you won't have a problem, as long as you didn't drill it out too large. Mine's been on since last august with no SES lights.

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

5 cold starts so far since installing it, no cel. the mbc i bought from birdley can't adjust low enough to keep me from fuel cutting in 3rd... my favorite gear. i got a nice cel from that tonight:)

i think i run a little richer now, i get more of a let off the gas backfire than what i did before, and my mileage seemed to go down a little faster after 1/4 tank.

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

remove the mbc when you get the cobb tuning software in your car.

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

i took it out because lowest possible setting caused fuel cut in 3rd. rock solid 1.2bar in first/second

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

should have bought a EVO subarus are junk :1

Re: subie thread v2: running full 3" turbo back with no cat, cel, issues?
 

if evos are so good, go ---- yourself, i don't care. i'm sticking with the wrx. buy your own evo.