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

Exhaust Question

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Old 06-28-2007 | 01:43 AM
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Default Need help planning my exhaust!

This is what I have so far:



Where would the o2's go. What would be the best location for the cutout?

Would the cat go right after the y-pipe?

Please help!
Old 06-28-2007 | 01:45 AM
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O2s Will go on the header collectors (Assuming your getting longtubes)

The cat will either be on the Y itself or right before the I pipe.

You can install cutouts before or after your cat, its your choice.

Tony.
Old 06-28-2007 | 01:47 AM
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What exactly do you have planned for headers and Y pipe? As for the cutout I'd put it right before the exhaust pipes turn to go over the axle. It has a opening that looks like it was meant for a cutout. With it right after the cat you will have clearance problems.
Old 06-28-2007 | 01:49 AM
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Originally Posted by Speed Density
O2s Will go on the header collectors (Assuming your getting longtubes)

The cat will either be on the Y itself or right before the I pipe.

You can install cutouts before or after your cat, its your choice.

Tony.
so I just have o2s in the collectors (im getting longtubes) and i get o2 sims for the second part? where would the I pipe be?
Old 06-28-2007 | 01:59 AM
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Most headers already have O2 bungs in them. The I pipe is the straight pipe after the Y pipe and before it turns over the axle. You don't even need O2 sims with a cat.
Old 06-28-2007 | 02:00 AM
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I updated the plan:


Old 06-28-2007 | 02:01 AM
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Originally Posted by porksoda
Most headers already have O2 bungs in them. The I pipe is the straight pipe after the Y pipe and before it turns over the axle. You don't even need O2 sims with a cat.
isnt there two o2 sensors? one in the collector area and the other is.... where?
Old 06-28-2007 | 02:06 AM
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You have 3 O2 sensors...1 in each header collector and one after the cat. The one after the cat just make sure the cat is functioning properly, no effect on mileage or anything. You can also buy a catted Y instead of a ORY this way you don't have to buy it all separately. Although I don't know which is the cheaper way besides not having a cat at all.
Old 06-28-2007 | 02:11 AM
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just out of curiosity...why even have a cat?
Old 06-28-2007 | 10:26 AM
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Originally Posted by LMz28
just out of curiosity...why even have a cat?
emissions, sound. i dont want the car to be too obnoxious.
Old 06-28-2007 | 10:39 AM
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Originally Posted by porksoda
You have 3 O2 sensors...1 in each header collector and one after the cat. The one after the cat just make sure the cat is functioning properly, no effect on mileage or anything. You can also buy a catted Y instead of a ORY this way you don't have to buy it all separately. Although I don't know which is the cheaper way besides not having a cat at all.

so the only important ones are in the collectors?

i already have a ory bought so thats not an option. catted y-pipes are around $500 and i got mine for $90.

do cats have a spot for o2s? do i even have to bother putting the cat one in?
Old 06-28-2007 | 11:05 AM
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Originally Posted by Speed Density
O2s Will go on the header collectors (Assuming your getting longtubes)

The cat will either be on the Y itself or right before the I pipe.

You can install cutouts before or after your cat, its your choice.

Tony.
can i install a cutout right after the y-pipe and get away with it? as in it not messing up my air/fuel ?
Old 06-28-2007 | 11:11 AM
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Originally Posted by Ironxcross
emissions, sound. i dont want the car to be too obnoxious.
time out...dont you need two cats though? or will you still pass with just one?
Old 06-28-2007 | 11:13 AM
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Originally Posted by Ironxcross
can i install a cutout right after the y-pipe and get away with it? as in it not messing up my air/fuel ?
i dont know how it is on your 97 but with my 95 (one 02 sensor) everything was perfect. you're probably gonna need a sim or tune it out so it doesnt throw a code.
Old 06-28-2007 | 05:58 PM
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would i be able to just go with lt headers, ory, and then a catback and then weld in my cut out/cat later?
Old 06-28-2007 | 06:01 PM
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Yes.

Any exhaust shop can do it.

Tony.
Old 06-28-2007 | 06:02 PM
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would i be able to go with pacesetter coated lts, pacesetter ory, and a magnaflow catback and have them all meet up and connect and weld in my cutout and cat later?
Old 06-28-2007 | 06:06 PM
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i dont know about ur cat but its possible. i have the exact mods
Old 06-28-2007 | 07:48 PM
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Originally Posted by razorclaw99
i dont know about ur cat but its possible. i have the exact mods
your ory pipe hooks right up to your catback ?
Old 06-28-2007 | 07:51 PM
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sorry for the all the obvious questions. i just want to be pretty sure about something before i drop a grand on it.

catbacks are a straightfoward install that doesnt require welding.. right?



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