Honda Prelude Forum

So whats the deal?

I have a CAT that seems to be clogging up, I have ordered a test pipe that has the flange for the o2 sensor. I'm putting this on my 1997 Base model, I guess my question is I am still OBDII so will the computer (learn) or try to fix itself to run more lean or rich if I take out the CAT to replace it with the test pipe? And will it throw a CEL?

Also please post up one's that have done a test pipe and also one's that have not and why they wouldn't install a test pipe. I'm still doing research on this matter, if it goes on and doesn't throw codes then I might keep it, if not then the test pipe will be on long enough for me to sell my old CAT on eBay, then with that money I'll get a new CAT (hi flow)

Thanks

by the way I did a search already on test pipes. Couldn't find anything but some people suggesting to put one on for performance gains and such.

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My cat was broken inside and blocking flow as well. I took mine out and just hollowed it. I didn't find the need to waste money on a part I didn't want to buy because I plan on getting a Random Tech. cat but didnt have 300 bucks to spring at the time. Since I had problems with mine I noticed a differance on how it ran and certainly had noticable more power. But as I said, it was suffering before. My CEL comes on about once a week and I just clear it at work with our scanner. After seeing the honeycomb I cant imagine how one would plug up with out some kind of engine problem. If you are just wanting to try something new I don't know if I would waste my time. Keep the cat and everything the way it's supposed to be. If you have a problem and don't mind a cel then swap it out. My milage was down from 27 ish to squeakin out 20-22 with out changing driving habits. If you have a problem you'll know.

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you'll throw a code. and you should be tuned for open exhaust.

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"I don't need the ratchet to reach yo azz, I'm old school I'll off you wit a piece of glass" KRS-ONE

loud and obnoxious
pollutes my air

street car = cat
race car = no exhaust

pick one.

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XXX Performance Honda/Acura Specialist - Tuning, Installation, Guidance
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New Race Motor Build Thread - 1998 Honda H2X Prelude

a lot of things pollute your air


i would go brand name high flow cat or unclog or hollow your current

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Not-on-the-H22-bandwagon: Member #7
De bladgroep
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92 Si :wof:

Yeah man my 74 Chevy polluted your air but now I consume less precious oil by about 70% so Im doin your environment a good service!

It's not really any louder. Maybe 3dB which is about the least gain that the average human ear can hear a difference between.

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it also makes the car sounds buzzy with no cat. unless you have a really quiet cat back on.

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94 si jdm h22 w/chipped p28
Georgia prelude club member #3
Georgia prelude club website
my ride<----check it out
MY 240 project~~ 300hp here i come

Yeah I guess I don't know what it would do with aftermarket exhaust. Mines factory and barely noticeable. At idle or low rpm its no different but under higher rpm with load its a little deeper. Sounds like an accentuated intake.

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i have had a test pipe for a year, worst idea ever i always had the code (o2 sensor main threshhold) not to say rich really rich, obd2 knows there is no cat and i just had problems from there,i just put my cat back on checkengine light went off.

I agree man, its just not worth it. Heres a guy on honda tech comparing sounds with the same exhaust and evreything just one video stock cat and one test pipe

Stock:
http://videos.streetfire.net/video/WS2Prelude_24176.htm

test pipe:


hopes that helps your decision...

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Member #2 of the Green Preludes for Life Club
http://preludezone.com/showthread.php?t=13736

No cat on an OBDII car should throw a code on the second O2 sensor, which doesn't determine your air/fuel, it's just a smog checker. If you go with no cat, pick up two spark plug antifoulers, drill one out, and slide your O2 sensor into that one, then put that into the unaltered one, and screw that into the sensor bung. That should keep you from throwing a code. I've heard several different exhausts with no cat, some sound fine, others sound terrible. A resonated test pipe will sound better than a hollowed cat or straight pipe

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My Cardomain

yea there are tricks to getting around the CEL. I forgot the exact specs but on my accord I spliced in 2 resistors to the rear O2 sensor and it fooled the cpu. If your exhaust is aftermarket i'd expect it to be really loud, smelly, and extremely raspy.

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sig # 2 by OceanBorn


Member #28 of the BB Squad

Raspy is an understatement Mark.
Unless it's a race car, don't do test pipe. It's annoying to you and everyone else, plus the fumes get in the car and the people behind you. It's nauseating.
-Speaks from past experience

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i have megan test pipe with there header and catback, at first it throw po420 than when i use the antifoulers it was ok but after 2 weeks it throw the
po133, so iam just resetting it and have not found a way to get rid of the cell i was going to get a new o2 sensor for the bank one but there was another guy in po.com had the same problem and it didnt help when he put the new one either.

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98 lude...sold
93 z32
03 zx6

If you're OBD2, you're going to throw a code with a test pipe. The guys at NTPOG made a "work around" that resets the ECU when you shut it off every time. I'm just not sure if it throws a code 20 minutes later or not.
For example, you can unhook the hose for your IAB's on your IM and it'll sputter a bit at idle, but supposedly help if you're running hard, at the drag strip or something, but after a few minutes, it's going to throw a code. You can reset it (disconnect the battery for a few minutes) and it comes back no code, but it'll come back if you don't hook that hose back up.

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CEL or not, i would avoid it just because of the sound lol. my accord had a test pipe and it was the loudest thing ever. wish i could get a video clip of it

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sig # 2 by OceanBorn


Member #28 of the BB Squad

hollowing out a cat is a horrible idea. jesus man, do you people not care about your environment?

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XXX Performance Honda/Acura Specialist - Tuning, Installation, Guidance
eCtune (Dealer) / Neptune (Dealer) / AEM / Kpro / S300 / Greddy Emanage / VAFC-SAFC
www.bbmoto.net
New Race Motor Build Thread - 1998 Honda H2X Prelude

Oh boy one car after the year 78 on the road and your going to get all EPA on us. LOL just kidding do some reserch on green house gases my friend your CAT is not helping that much. It might help the smell but not the flurocarbons. If you refer back to my thread, the test pipe is just a temp until I get my old CAT sold on eGay to help in funding my new hi flow CAT. Seems I will have to cut all my bolts as they are pretty much welded. So the new test pipe I got for like $30 to include the shipping which was a rip off, test pipe was only $10. Well anyways it comes with all new hardware and gaskets so very good temp fix until I can find me a CAT replacement, so I guess next question is what good Hi Flo Cat could I get that has flanges and will promote high performance or is there such a beast?

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