Hi Flow Cat

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Tonyd0821

Banned
hey, im doing my greddy install in 2 weeks on my 96 civic ex coupe, and today am going to go get a hi flow cat.

the problem i have is that the guy @ the muffler shop said that any hi-flow cat will become clogged after a while due to the blue box making the fuel rich.

is this true?

he was going to give me one of his normal aftermarket hi flow cats. its not a import performance shop, so i dont think the cat is a brand name you guys have heard of.

whats the deal? will the blue box even make a hi flow cat clogged after a while?

what should i do? thanks

p.s. vfac, etc etc etc , is out of my price range for about 6 months. so im forced to run blue box untill then.
 
I don't know what brand of catalytic converter your guy is telling you about, but think about it... if a high-flow cat flows more air than a normal cat, wouldn't you think that it would be harder to clog? It's catching less physical mess on the way out, or at least that's what you assume since it flows better- so wouldn't you assume that it would take a longer time to clog?

That may or may not be true, but take my experience...

My B20/VTEC setup was always running super rich. My stock cat didn't clog after 10k+ miles, and the Random Tech hasn't ever clogged up either. I'm guessing I have 35k+ on the Random Tech.
 
ok. went to the muffler shop, and he said that because my car is obd2,
it would throw a cel with a hi flow cat.


and he also said that a turbo @ stock boost would melt the y8 pistons LOLOLOLOLOLOLOLOL
found that rather amusing.
 
I think that you can safely ignore this exhaust shop guy's opinion.
 
Originally posted by lsvtec@Jun 10 2003, 04:06 PM
I think that you can safely ignore this exhaust shop guy's opinion.

well ya, about the pistons melting.... that was rather amusing.

but u think a CARSOUND hi flow cat would throw a cel like he said it would?

wonder if i put a 95 civic ex ecu onto my car.....if that will make my car obd1 and i can
just snip off the 02 sensor on the cat...
 
i thought greddy didnt make turbo kits for 96-98 civic?
i think if you got a hi flow cat with with the hole for the O2 sensor you wouldnt throw a code.
 
Originally posted by SpyOneUSN@Jun 10 2003, 07:08 PM
i thought greddy didnt make turbo kits for 96-98 civic?
i think if you got a hi flow cat with with the hole for the O2 sensor you wouldnt throw a code.

greddy doesnt. im modifying (what the fuck is up with my spelling today???? i was an english major in college)
the 15g kit to fit onto a obd2 car.

from what im told, i got a 50/50 chance of throwing a cel when i put the hi flow cat on. even if it does have the
o2 bung on it.

im looking for a o2 simulator that i can hook up to my ecu, and i think that might get rid of the cel.
 
Originally posted by lsvtec@Jun 10 2003, 07:28 PM
Get a conversion harness and run an OBD1 ECU.

thats 245-ish dollars....

codee says it isnt worth it...

what else would i gain from going obd2-1 besides by passing the o2 sensor on the cat?
 
The ability to run a Hondata.

I bet you can find that harness for less than $245.

C-speed racing has them for $200. I bet with a little more hunting you could do better than that.
 
Originally posted by lsvtec@Jun 10 2003, 09:39 PM
The ability to run a Hondata.


hondata was my next planned upgrade after the turbo is installed.....

i CANT run hondata because my car is obd2?


this is not good.
 
first off stock civics don't have secondary O2 sensors so you probably won't throw a code, also depending on the application hondata has modified obd1 ecu's that have obd2 plugs otherwise you need the conversion harness and a hondata ecu
 
:rolleyes: Yeah, I am sorry to tell you, 6th gen's run one after/before the cat mang. One or the other, I know they have 2 o2 sensors atleast for a fact. It's obd2 not obd1 or obd0.
 
Originally posted by Slammed89Integra@Jun 10 2003, 11:50 PM
:rolleyes: Yeah, I am sorry to tell you, 6th gen's run one after/before the cat mang. One or the other, I know they have 2 o2 sensors atleast for a fact. It's obd2 not obd1 or obd0.

ya i knew that allready. also cuz we lifted the car up and i saw the secondary o2 sensor on the cat....

i wanted to rip it out and eat it i was so pissed.
 
that car sound cat is pretty good from what i hear, the guys on the oldone.com use it and they know there shit, but carsound has a dyno comparing it to random and the random make a little more peak but the carsound has more through the middle, both are good.

on that greddy kit, make sure you have the same ecu that the blue box is made for or it won't work very well. this is what happen to me i have a 97 obd2 and the blue box is for the 99 obd2 , same engine and the box throws a cel at idle and runs way rich on top end so rich it runs off the chart on the dyno. not good for hp.

if your going to use an o2 simulator first try the cat my thought is that is won't throw the cel but if it does and make sure its not the blue box (check the code for the cel first) then i would get the sim, jegs.com has them for imports(made from caspers i think) and they have the wiring instructions.

you should make up your mind first if your going with the hondata so you dont waste your money on all that 02 sim and the blue box wont work very well with any ecu except the one its made for. hope it helps .
 
One more thing, there are at least two different kinds of ob2. there is the obd2a and the obd2b. you might even have another version. i learned this the expensive way. greddy will be able to help you.
 
Originally posted by karnash+Jun 10 2003, 08:35 PM-->
@Jun 10 2003, 09:39 PM
The ability to run a Hondata.


hondata was my next planned upgrade after the turbo is installed.....

i CANT run hondata because my car is obd2?


this is not good.

Here the list of ECU's that the Hondata will work with:
http://www.hondata.com/ecus.html
None of them are OBD2. You are going to have to buy the wiring adapter and an OBD1 ECU to run a Hondata, but like I said you should be able to get the harness for less than $200 if you look around.
 
Originally posted by Baker@Jun 10 2003, 09:42 PM
first off stock civics don't have secondary O2 sensors so you probably won't throw a code, also depending on the application hondata has modified obd1 ecu's that have obd2 plugs otherwise you need the conversion harness and a hondata ecu

You're 0 for 2 today, where is this OBD1 ECU with OBD2 plugs? It isn't on the Hondata site. The only way I have ever seen this done is with the adapter harness.
 
To get back to the original post. It won't clog the cat. The Random Technology cat is a honeycomb packing. It will be fine. They use a bigger honeycomb packing than stock cats. The packing is shorter than stock too. If the cat you are getting is the "screen type packing" Then it might be more prone to getting clogged due to the tighter packing. But believe me you will be fine!
 
i have a 00 civic si turbio and i got a straight pipe exhaust no cat and i havent thrown a cell yet for the secondary o2 sensor ,but i do have a cel 41 for the primary o2 sensor
 
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