LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Gutting the Cats.

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Old Mar 25, 2008 | 01:34 PM
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Default Gutting the Cats.

I'll say after feeling the exaust coming out of the tail pipes, these exaust systems are restricted bad, even with the Cat backs & Magna-flow muffler, its still a joke, so for the meen time, i'll just gut the cats on this thing, i'm sure thats were most of the restriction is, i just got it inspected, so its good for 2yrs., by then i'll most likely have headers & a true dual system. What have some of you used to gut them, or is there pre-made pipes that will go in there place? I wouldn't expect any muffler place to do this for me seeing most can't, will doing this mess with the O2 sensers or computer?

Has anyone just gutted there cats, what gains have you seen?
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Old Mar 25, 2008 | 01:39 PM
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Gutting the cats will do nothing for power. The guy installing my headers on my old 97 took it upon himself to do that also . Only thing you'll get is a new annoying sound. being in jersey and knowing I was going to fail the sniffler I picked up a high flow cat from summit for 50 bucks.
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Old Mar 25, 2008 | 01:41 PM
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gutting the cats is stupid...

cut them out and weld in new pipe...

plus you can sell the cats for 150$ easy!
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Old Mar 25, 2008 | 02:05 PM
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Originally Posted by VendettaV6
gutting the cats is stupid...

cut them out and weld in new pipe...

plus you can sell the cats for 150$ easy!
Very true. Take them out, make the car sound better and make some dough! My buddy gutted the cat on his car and it sounds like crap I wouldnt recommend.
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Old Mar 25, 2008 | 02:07 PM
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Ok then i won't gut them, but if i replace them with pipe, will i notice anything or is most the power in a set of Headers? Are stock manifolds thet restrictive on these things? I would think you should be able to feel some pressure against your hand holding it over the tail pipes, i barely feel any.
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Old Mar 25, 2008 | 02:10 PM
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Originally Posted by LM97Z
Ok then i won't gut them, but if i replace them with pipe, will i notice anything or is most the power in a set of Headers? Are stock manifolds thet restrictive on these things? I would think you should be able to feel some pressure against your hand holding it over the tail pipes, i barely feel any.
Yea the manifolds are very restrictive, the real power comes from upgrading to some LT's or Mids atleast.
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Old Mar 25, 2008 | 02:22 PM
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Just leave it as it is until you upgrade w/ headers...If you do gain anything(which you probably wont) from the pipe your not gonna feel it anyway.
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Old Mar 25, 2008 | 02:29 PM
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When i send these Pro-star wheels back, i'll order some LTs, what about cut-outs too?
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Old Mar 25, 2008 | 02:40 PM
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Originally Posted by LM97Z
When i send these Pro-star wheels back, i'll order some LTs, what about cut-outs too?
What about them? You already have a catback, if you wanna chop it up to gain a few hp and probably make your car sound like a dump truck go ahead...Your talking about very small gains here that you wont even feel. I reccomend doing some research on 4th gen exhaust systems/upgrades.
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Old Mar 25, 2008 | 03:10 PM
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Originally Posted by MonmouthCtyLS7
What about them? You already have a catback, if you wanna chop it up to gain a few hp and probably make your car sound like a dump truck go ahead...Your talking about very small gains here that you wont even feel. I reccomend doing some research on 4th gen exhaust systems/upgrades.

Bare with me if i don't understand all the slang, i'm new to these newer cars, i thought cutouts were like Dumps just after the headers, where you can blocks them off or open them up when needed (like at the track).

What do "Cutouts" really mean?
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Old Mar 25, 2008 | 03:47 PM
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u got the idea.it just doesnt do much unless you have a cam or turbo/blower
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Old Mar 25, 2008 | 05:30 PM
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Originally Posted by m6ttop
u got the idea.it just doesnt do much unless you have a cam or turbo/blower

Thanks
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Old Mar 26, 2008 | 01:39 AM
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wouldnt recommend just cutting the cat off for sound either... i had to have mine removed about 3 weeks ago because it was so clogged you couldnt shine a light through it... and i wouldnt drive the car after they did this because i just hated the sound sooooo much... i was embarrased to drive it and only drove it one time after they did that, and that was back to the shop to put something new on...
and a cutout is basically a piece of pipe that is in the shape of a y... one piece flows regularly and is normally welded in to your system, and the other piece is about 2'' and has either a cap with wingnuts on it, or you can get one with an electric opener, but the purpose is that you can either stick with your full exhaust, or if you want your car's exhaust to be loud and have some crazy rumble to it, the exhaust comes out before the converter and muffler, and basically is like having open headers with no exhaust, but you still have the luxury of having exhaust if you want it... if that makes sense lol


here is a link to give you a better view of what a cutout actually is... http://www.jegs.com/p/JEGS/751312/10002/-1/11529
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Old Mar 26, 2008 | 04:10 AM
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You could have a dual cat car, I have 2 cats on my 97 Z28. I am pretty sure some cars came with 1 and some came with 2 for some reason. Anyways what I am going to do is when I install FL headers I am taking off the cats, it will free up some ponies (Ive actually heard up to 10rwhp on dual cat cars) and also shed a few pounds. I have o2 sims so I dont get any cat codes until I get a tune then will just delete rear o2 codes. Gonna try to find a cat (I found flowmonster to be the best doesnt have all that bulky metal **** covering the cat) and cut it down the middle top to bottom and put some kind of hinge and lock on it and slip it over my pipe for aesthetic purposes when needed. Just an idea I am gonna try out.
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Old Mar 27, 2008 | 04:31 PM
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i believe if your car is 95 or older it should be obd 1 and there wont be o2 sensors after the cats ....i live in new hapshire and for inspection they hook up to the obd2 port for emmisions instead of hooking **** up to the tailpipe and if the cats are empty the computer will now but if its obd 1 then they cant tell if the cats are empty but they have to see that they are there. so in my case were i have a 94 the best way to do it is to hollow the cat and then run a straight pipe through the cat to make a smooth flow.
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Old Mar 27, 2008 | 06:42 PM
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anyone heard of them eliminating emmisions for obd1 in october. I heard of this in MA at least
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Old Mar 27, 2008 | 06:43 PM
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if this is tru i think i may gut my cat when i get some headers
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Old Mar 27, 2008 | 07:25 PM
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I won't gut mine now, just install some LTs & ory pipe, either i'll save the cats or sell them. it has 2, one just below the manifold flange n the drivers side, other is back on the pass side pipe.
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Old Mar 27, 2008 | 08:36 PM
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pete where in new hampshire? u wouldnt of happen to just purchuse a green 94 z28 recently?
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Old Mar 27, 2008 | 09:26 PM
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Originally Posted by blackbird94
anyone heard of them eliminating emmisions for obd1 in october. I heard of this in MA at least
For all 95 and older vehicles, There will be a two speed idle test. There will be no emmisions exemptions. However, the idle test is MUCH easier to pass.

BTW, Im in Truro.
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