How will knocking out cats effect my computer
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Joined: Dec 2001
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From: Pascagoula Ms
How will knocking out cats effect my computer
I have a 94 coupe. I am thinking of punching out my cats but leaving the pre cats alone. Also going to a more freeflow muffler. How will this effect my computer. Will this give me errors? How much hp should I gain? Thanks terry
tbmoore@cableone.net
tbmoore@cableone.net
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From: Orange Park Florida
Re: How will knocking out cats effect my computer (tbmoore)
Well it will keep the furrrrrr off the keyboard.....don't let them sit on the monitor, they may pixx in it....
other than that.....leave the furry beasties alone....;-)))
GENE
other than that.....leave the furry beasties alone....;-)))
GENE
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Joined: May 2001
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Re: How will knocking out cats effect my computer (tbmoore)
Well a little bit of correction. Your 94 should only have 2 cats, no precats.
O2 sensors could be different. If you only have 2, one in front of each cat you can get rid of the cat without any trouble. If you have 4 you will need O2 simulators to trick your computer into thinking the cat is still intact.
O2 sensors could be different. If you only have 2, one in front of each cat you can get rid of the cat without any trouble. If you have 4 you will need O2 simulators to trick your computer into thinking the cat is still intact.
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From: Pascagoula Ms
Re: How will knocking out cats effect my computer (Nathan Plemons)
It has two pre cats. An 02 sensor in front of each one and one sensor behind the passenger side pre cat which I was told was an experiment for later models and did not control. After pre cats y's together and goes into the cat then back out the the mufflers. would leave the pre cats with the 02 sensors in place. and clean out the main cat. I know someone has tried this on stock 94 lt1. Just wanted to know what problems and how much power gain. thanks terry
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From: Pascagoula Ms
Re: How will knocking out cats effect my computer (bwagner)
So which is the rosonator and which is the cats? Are the two smaller asylemblies near the engion resonators and then the larger piece which both tubes go thru the cat?
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From: Dallas TX
Re: How will knocking out cats effect my computer (bwagner)
Here's a picture of my exhaust ... 
The place where the aluminum pipes are is where the resonator used to be. It's NOT a cat.... the cats are right under where your feet are in the car.
The place where the aluminum pipes are is where the resonator used to be. It's NOT a cat.... the cats are right under where your feet are in the car.
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From: Pascagoula Ms
Re: How will knocking out cats effect my computer (tbmoore)
Now do I need to remove the resonator-- is it causing back pressor-- will removing it cause poor sound...Should I just run with the cats and muffler.. also how much power gain should I get? thanks for the pics.
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
Re: How will knocking out cats effect my computer (tbmoore)
Leave the cats in place, you can never tell when emissions laws will jump up and bite from behind. The resonator should not be a HP drain. You may want to try removing the mufflers and having a exhaust shop just run straight pipes. Cut the tips off the OEM mufflers and put them back on the pipe.
You may not see a big gain if you do this, but the B&B Tri-Flos I have were only supposed to be good for about 10HP.
You may not see a big gain if you do this, but the B&B Tri-Flos I have were only supposed to be good for about 10HP.
Drifting
Joined: Jan 2002
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From: I Hate Tourists FL
Re: How will knocking out cats effect my computer (tbmoore)
I have a 93, I cut the cats out and welded in 2 straight pipes and then replaced the resonater with an x-pipe and 2 flowmasters. The sound is awesome even better when you stomp on it. I dont think any state in the south has or will have emission standards atleast in my life time anyway. Cut the cats out it makes things a lot easier to get too like the fuel filter and the o2 sensors..You will also notice a definate seat of the pants feel when you cut them. I could only bark my tires on the start with mine now they bark in first and second and I have an auto. :yesnod: :jester
Also you can pretty much trust Nathan Plemons he know's his stuff...helped me out of a couple of holes! Not trying to suck up but I owe him a couple of beers he's saved me a few headaches. :cheers: :yesnod:
[Modified by 93Zeus, 8:05 PM 1/31/2002]
Also you can pretty much trust Nathan Plemons he know's his stuff...helped me out of a couple of holes! Not trying to suck up but I owe him a couple of beers he's saved me a few headaches. :cheers: :yesnod:
[Modified by 93Zeus, 8:05 PM 1/31/2002]
Melting Slicks
Joined: Oct 2001
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From: Cary NC
Re: How will knocking out cats effect my computer (93Zeus)
They may not do emissions in your part of the south but they do in NC. It's actually the biggest part of getting your sticker. The physical inspection seems almost cursory...
I've been told by some folks that hey had an LT1 pass emissions with the cats removed. But I'm not sure how much of that I buy.
When they put my92 LT1 (80Kmi) on the machine it passes all 3 parts of the emissions test. And just as low as my kids 4 and 6 cylinder cars. And 2 of them are 99s with 30Kmi on them!
So the LT1 does run pretty clean from that standpoint.
Graham
I've been told by some folks that hey had an LT1 pass emissions with the cats removed. But I'm not sure how much of that I buy.
When they put my92 LT1 (80Kmi) on the machine it passes all 3 parts of the emissions test. And just as low as my kids 4 and 6 cylinder cars. And 2 of them are 99s with 30Kmi on them!
So the LT1 does run pretty clean from that standpoint.
Graham
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Joined: Apr 2001
Posts: 22,267
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From: Dallas TX
Re: How will knocking out cats effect my computer (93Zeus)
I have a 93, I cut the cats out and welded in 2 straight pipes and then replaced the resonater with an x-pipe and 2 flowmasters. The sound is awesome even better when you stomp on it. I dont think any state in the south has or will have emission standards atleast in my life time anyway. Cut the cats out it makes things a lot easier to get too like the fuel filter and the o2 sensors..You will also notice a definate seat of the pants feel when you cut them. I could only bark my tires on the start with mine now they bark in first and second and I have an auto. :yesnod: :jester
Also you can pretty much trust Nathan Plemons he know's his stuff...helped me out of a couple of holes! Not trying to suck up but I owe him a couple of beers he's saved me a few headaches. :cheers: :yesnod:
[Modified by 93Zeus, 8:05 PM 1/31/2002]
Also you can pretty much trust Nathan Plemons he know's his stuff...helped me out of a couple of holes! Not trying to suck up but I owe him a couple of beers he's saved me a few headaches. :cheers: :yesnod:
[Modified by 93Zeus, 8:05 PM 1/31/2002]
Team Owner
Joined: Apr 2001
Posts: 22,267
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From: Dallas TX
Re: How will knocking out cats effect my computer (ASRoff)
DO-H!!!!! Glock you painted the driveway!!!!!! :smash: :jester :cheers: :seeya