HUH?
Thread Starter
Pro
Joined: Sep 2001
Posts: 685
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From: Houston, TX
HUH?
I keep hearring people talk about pre cats? I have a 94. I thought that the manifolds went to two cats then down to a resonator then to two mufflers...correct? Also....can you gut the cats on a 94 and not throw any codes? Is it loud? any losses? gains? i know sometimes backpressure is required.
Le Mans Master
Joined: Feb 1999
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From: Stoplight City IN
S. Indiana Events Coordinator
Cruise-In I Veteran
Re: HUH? (Torquem)
The 86 - 89?? had a "pre cat" that was south of the headers. One on each side, then the pipes Y'ed in to the main cat, then Y'ed again out to each side of the car.
Give me a minute, and I'll show you a picture :)
[Modified by SaveTheWave, 8:48 AM 1/6/2002]
Give me a minute, and I'll show you a picture :)
[Modified by SaveTheWave, 8:48 AM 1/6/2002]
Melting Slicks
Joined: Aug 2000
Posts: 2,009
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From: Springfield MO
Re: (SaveTheWave)
I gutted mine, didn't cost me a thing. Well, a couple hours of my own labor. I cut the top half of the open, leaving a flap. I removed the cats and then welded the flap shut. No leaks, No codes, and I can hear my cam a little better. I don't have any track times or dyno numbers, but I had to do something about one cat because it was busted and knocking like crazy.
Team Owner
Joined: Sep 2001
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Re: (scorp508)
The 84-85 exhaust had no precat, only a main cat.
The 86-90 exhaust had two precats going into a main cat.
ZR-1s have no precats, only a resonator and a main cat.
LT1's have two small cats on each side that lead into the resonator.
correct me if im wrong.
The 86-90 exhaust had two precats going into a main cat.
ZR-1s have no precats, only a resonator and a main cat.
LT1's have two small cats on each side that lead into the resonator.
correct me if im wrong.
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Le Mans Master
Joined: Feb 1999
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From: Stoplight City IN
S. Indiana Events Coordinator
Cruise-In I Veteran
Re: (vader86)
I belive the ZR1 had a huge pre cat right off of each header. Maybe it's not a pre-cat, but there is definitely a huge round thing there.
Race Director
Joined: May 2000
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From: No more yankee my wankee, the Donger is tired!
Re: HUH? (SaveTheWave)
Is that a precat or something else?
Le Mans Master
Joined: Mar 1999
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From: McAlester Oklahoma
Re: (Justin1984)
Doesn't removing the catalyst send your O2 sensor berserk? :confused:
[Modified by Justin1984, 5:57 AM 1/7/2002]
[Modified by Justin1984, 5:57 AM 1/7/2002]
Race Director
Joined: May 2001
Posts: 14,165
Likes: 9
Re: HUH? (Torquem)
Yup, your 94 has two that look just like the ZR-1. You can get rid of them without any problems. It's only the 96 (95 also maybe?) cars that have 4 o2 sensors that get pissed if you remove the cats.
Le Mans Master
Joined: Oct 1999
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From: Sachse Texas
Cruise-In I Veteran
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Re: HUH? (Torquem)
I keep hearring people talk about pre cats? I have a 94. I thought that the manifolds went to two cats then down to a resonator then to two mufflers...correct? Also....can you gut the cats on a 94 and not throw any codes? Is it loud? any losses? gains? i know sometimes backpressure is required.
