bypassing the cats ??
#1
Instructor
Thread Starter
bypassing the cats ??
the catacylic converter's just went out on my 94 . and was considering bypassing them . what will happen ? mess with the o 2 sensors? and how much louder will it get ? can anyone who did this let me know the results ? thanks
#2
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I had a friend take a bad cat off (not a Vette though) and knock the ceramic guts out of it with a piece of rebar. Then, it was just an empty fat place in the exhaust pipe. Didn't notice the sound changing all that much and the car didn't run any better than before the cat failed. No inspection sniff test so it passed visual. Not a recommended fix.
#3
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What were your syptoms? I've got a 94 LT1 with 114 K miles on it and it has the orginal cats. I've been thinking about replacing or eleminating them.
I don't want to get on a road trip and have problems 1000 miles from home.
I don't want to get on a road trip and have problems 1000 miles from home.
#5
Drifting
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I have empty cats on my Vette. Car runs fine.
I changed out to get a little more power on the drag strip. At the same time I put on some Magnaflow mufflers. So I can't tell you if removing the cats make the car louder on not. But the car will not pass emissions inspection now.
I changed out to get a little more power on the drag strip. At the same time I put on some Magnaflow mufflers. So I can't tell you if removing the cats make the car louder on not. But the car will not pass emissions inspection now.
#6
Le Mans Master
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No biggie either way...
Cats get their share of print on the ZR-1 boards too. Marc Haibeck is one of the professional gurus of that machine, and according to dyno testing w/ and w/o the (new performance) cats, the difference was about 5 hp on the 500 hp LT5s...no real hit to performance except to bragging rights, apparently.
Looking for a bit more "snap", I've gone to the Fidanza FW and will be installing a gear in the rear; the effect of reinstalling cats (if I choose to) will be lost in the real torque increases afforded by those changes. I'm currently not running cats, but I don't get too excited either way, far as performance goes.
P.
Looking for a bit more "snap", I've gone to the Fidanza FW and will be installing a gear in the rear; the effect of reinstalling cats (if I choose to) will be lost in the real torque increases afforded by those changes. I'm currently not running cats, but I don't get too excited either way, far as performance goes.
P.
Last edited by Paul Workman; 04-07-2010 at 08:35 AM.
#7
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I read in an import tuner magazine (dentists office?) that straight pipes gave you a tiny bit more top end power, almost in-perceivable; where bashing out the innards of a CAT you can actually lose a small amount due to the turbulence created in the gas flow. Either way, nothing in the seat of the pants feel.
In RI straight pipes wouldn't pass emissions on a pre-obdII post antique car...
In RI straight pipes wouldn't pass emissions on a pre-obdII post antique car...
#8
Drifting
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Cats get their share of print on the ZR-1 boards too. Marc Haibeck is one of the professional gurus of that machine, and according to dyno testing w/ and w/o the (new performance) cats, the difference was about 5 hp on the 500 hp LT5s...no real hit to performance except to bragging rights, apparently.
Looking for a bit more "snap", I've gone to the Fidanza FW and will be installing a gear in the rear; the effect of reinstalling cats (if I choose to) will be lost in the real torque increases afforded by those changes. I'm currently not running cats, but I don't get too excited either way, far as performance goes.
P.
Looking for a bit more "snap", I've gone to the Fidanza FW and will be installing a gear in the rear; the effect of reinstalling cats (if I choose to) will be lost in the real torque increases afforded by those changes. I'm currently not running cats, but I don't get too excited either way, far as performance goes.
P.
#9
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Hey keep in mind I read it in import tuner magazine....going from 140HP to 143HP...yeee haaa
#10
Drifting
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I really did not get any 'seat of the pants' increase at all. But it was sure nice to get into the 13s at the strip though.
Last edited by Doug 87L98; 04-07-2010 at 11:49 AM.
#11
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