Info on x-Pipe, Cats? True duals? Help!!
05-29-2015, 01:36 PM
#1
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Join Date: Oct 2012
Posts: 17
Info on x-Pipe, Cats? True duals? Help!!
Hey lookin for some answers on what probably to most of you is basic stuff. I currently have a SLP Loudmouth 1 exhaust system on my 2000 SS. Everything else stock. LT headers are next . I'm choosing X-Pipe over Y-pipe. This is where I'm confused. I hear things like (True duals) , (No Cats) , ( cutouts) ( straight pipe)
1. Does putting on an X-Pipe replace the cats.
2. Does the X-pipe eliminate the need for a muffler(resonator)
3.how do u eliminate the cats within an X-pipe?
4. Is an X-Pipe the same as going straight Pipe?
5. Is all u need headers , X- pipe and tips to complete a system?
Planning on also going CME tips
1. Does putting on an X-Pipe replace the cats.
2. Does the X-pipe eliminate the need for a muffler(resonator)
3.how do u eliminate the cats within an X-pipe?
4. Is an X-Pipe the same as going straight Pipe?
5. Is all u need headers , X- pipe and tips to complete a system?
Planning on also going CME tips
05-29-2015, 04:04 PM
#2
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Join Date: Nov 1998
Location: Hell was full so they sent me to NJ
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Re: Info on x-Pipe, Cats? True duals? Help!!
A Y-pipe combines the outlets of the two header collectors into a single intermediate pipe, single muffler. The single intermediate pipe and muffler is called a "catback".
An X-pipe merges the outlets of the two header collectors into a single merge, and immediately splits into two pipes back to the rear of the car. The theory is this evens out the pulses in the exhaust system and increase power. Haven't actuall seen a dyno test that proves this. This is one way to build "true dual exhaust".
Another way to build a true dual exhaust is to simply run a pipe from each collector to the rear of the car.
None of the above determines whether you run cats, or run a muffler/mufflers.
Typically, you bolt the cats to the header collectors. The cats have to be close to the engine to keep the O2 sensors hot and accurate. Whether you need cats depends on local emissions testing. You can use cats with a Y-pipe, an X-pipe, or two straight pipes back the the rear of the car.
You can put a muffler anywhere you want in the system. Typically, it/they go behind the rear axle. If you run a Y-pipe and catback, which nets you a single intermediate pipe to the rear of the car, you use a single muffler. That would be like the stock setup, and the muffler can have a single outlet or a pair of outlets to simulate the appearance of the stock setup.
You can also put a muffler in each of the two pipes going back to the rear of the car, whether they come from an X-pipe, or directly from the header collectors. You may be able to fit the mufflers into the pipes before the axle, or after the axle.
An X-pipe merges the outlets of the two header collectors into a single merge, and immediately splits into two pipes back to the rear of the car. The theory is this evens out the pulses in the exhaust system and increase power. Haven't actuall seen a dyno test that proves this. This is one way to build "true dual exhaust".
Another way to build a true dual exhaust is to simply run a pipe from each collector to the rear of the car.
None of the above determines whether you run cats, or run a muffler/mufflers.
Typically, you bolt the cats to the header collectors. The cats have to be close to the engine to keep the O2 sensors hot and accurate. Whether you need cats depends on local emissions testing. You can use cats with a Y-pipe, an X-pipe, or two straight pipes back the the rear of the car.
You can put a muffler anywhere you want in the system. Typically, it/they go behind the rear axle. If you run a Y-pipe and catback, which nets you a single intermediate pipe to the rear of the car, you use a single muffler. That would be like the stock setup, and the muffler can have a single outlet or a pair of outlets to simulate the appearance of the stock setup.
You can also put a muffler in each of the two pipes going back to the rear of the car, whether they come from an X-pipe, or directly from the header collectors. You may be able to fit the mufflers into the pipes before the axle, or after the axle.
05-29-2015, 04:20 PM
#3
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Join Date: Nov 1998
Location: Hell was full so they sent me to NJ
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Re: Info on x-Pipe, Cats? True duals? Help!!
These are examples of a Y-pipe with a cat in each branch of the Y:
[img]
[/img]
This is a catback exhaust:
This as a 4" catback for high HP applications:
This an X-pipe, with cats at the outlet of each collector:
Here's a setup with mufflers on each header collector, no cats, and straight pipes back to the rear axle, with turndowns:
[img]
[/img]This is a catback exhaust:
This as a 4" catback for high HP applications:
This an X-pipe, with cats at the outlet of each collector:
Here's a setup with mufflers on each header collector, no cats, and straight pipes back to the rear axle, with turndowns:
05-29-2015, 05:42 PM
#4
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Join Date: Oct 2012
Posts: 17
Re: Info on x-Pipe, Cats? True duals? Help!!
Wow that was a lot of help , but I definitely have made me rethink the whole X-pipe setup if u say in fact there is no proof that it's a better gain. In a way a new y-pipe and lt headers would be an easier setup to install since it's just replacing stock parts right
04-17-2017, 06:40 PM
#5
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Join Date: Jan 2010
Location: Philadelphia, PA
Posts: 34
Re: Info on x-Pipe, Cats? True duals? Help!!
Wow that was a lot of help , but I definitely have made me rethink the whole X-pipe setup if u say in fact there is no proof that it's a better gain. In a way a new y-pipe and lt headers would be an easier setup to install since it's just replacing stock parts right
04-17-2017, 08:50 PM
#7
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Join Date: Jan 2010
Location: Philadelphia, PA
Posts: 34
Re: Info on x-Pipe, Cats? True duals? Help!!
I picked up a near stock 97 LT1, just has an exhaust cutout in front of the muffler. I'm thinking of leaving everything the way it is and putting on longtubes and a y-pipe. I'm thinking that a catback exhaust (like a loudmouth or similar) won't be necessary with exhaust cutout. Would I have to buy anything else to make the longtubes and y-pipe work? Not trying to hijack the thread but I think this helps answer the OP's question.
http://www.ebay.com/itm/93-97-Camaro...hUkzVM&vxp=mtr
Last edited by Longwell; 04-19-2017 at 07:40 AM.
04-19-2017, 05:26 PM
#8
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Join Date: Nov 1998
Location: Hell was full so they sent me to NJ
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Re: Info on x-Pipe, Cats? True duals? Help!!
Don't worry about hijacking, the Thread Staarter hasn't signed into this site since his last post above, 2 years ago.
You have to check the specific rules for emissions inspection. Technically, long tube headers can never be emissions legal on an LT1 car. Federal law prohibits changing the number of cats on the car, or changing the location of the cats. Long tube move the cats back from their original location. Not all states enforce Federal law. California does, don't know about urban Pennsylvania. Friends living in rural PA seem to have little in the way of inspections. Then, does PA require CARB-EO certification on aftermarket performance parts? For headers, that's a metal tag, welded to a primary, with the CARB-EO certification number on it. Long tubes can't get that because of Federal law.
But, many jurisdictions really don't care as long as your car passes the tailpipe test, PCM has no codes, and the car has cats. You could have long tubes, a cat on each collector. 3" CarSound cats are good. I ran them on my custom Y-pipe. They were flanged and bolted so I could remove them at the track, because I trun highly leaded racing fuel, and lead does not play well with cats and O2 sensors. We checked it on a PA emissions dyno (engine was built in PA) and it passed NJ standards. But I never had it inspected in NJ, since it was pretty much limited to being a track car. Now in NJ, 95 and older to not have any inspections at all - no emissions, no safety - and no sticker.
Let's say you get long tubes, and a duel cat Y-pipe. First question is will that Y-pipe even connect to the stock intermediate pipe? By the time you put LT's on, with a catted Y-pipe, you have used up a lot of real estate under the car. And a cutout would add a few inches more to the setup. But it really makes no sense at all to spend money on long tubes, high flow cats, and a Y-pipe, and then try to force the exhaust through the stock 2.75" crimp-bent intermediate pipe. Sure, you have a cutout.... but are you going to drive around with it open all the time? If you can get away without a ticket for excessive noise, are you sure you want to damage your hearing with all that constant racket entering the passenger compartment? My hearing is seriously damaged by loud cars and loud concerts.... sure, I'm older than dirt, but hearing loss is really not a lot of fun, no matter how old you are.
I know for many years Old Bridge Raceway Park here in NJ would not allow open exhaust of any kind except on Sundays (and NHRA events). I replace the cats with Borla XR1 mufflers, and the straight pipes, and had to angle the turndowns back by the axle inwards, to try and keep the noise under the car, to beat the sound meters in techj, and on the starting line. Then they realized what people were doing, and added a spec that required mufflers with at least 4 baffles. That's when I stopped going there.
A 3" catback will pick up maybe 10HP over the stock 2.75" system, even on a pure stock engine. That HP will be nice to have, when you are cruising with the cutout closed, and want to have some fun. I guess you could go with an electric cutout.
You have to check the specific rules for emissions inspection. Technically, long tube headers can never be emissions legal on an LT1 car. Federal law prohibits changing the number of cats on the car, or changing the location of the cats. Long tube move the cats back from their original location. Not all states enforce Federal law. California does, don't know about urban Pennsylvania. Friends living in rural PA seem to have little in the way of inspections. Then, does PA require CARB-EO certification on aftermarket performance parts? For headers, that's a metal tag, welded to a primary, with the CARB-EO certification number on it. Long tubes can't get that because of Federal law.
But, many jurisdictions really don't care as long as your car passes the tailpipe test, PCM has no codes, and the car has cats. You could have long tubes, a cat on each collector. 3" CarSound cats are good. I ran them on my custom Y-pipe. They were flanged and bolted so I could remove them at the track, because I trun highly leaded racing fuel, and lead does not play well with cats and O2 sensors. We checked it on a PA emissions dyno (engine was built in PA) and it passed NJ standards. But I never had it inspected in NJ, since it was pretty much limited to being a track car. Now in NJ, 95 and older to not have any inspections at all - no emissions, no safety - and no sticker.
Let's say you get long tubes, and a duel cat Y-pipe. First question is will that Y-pipe even connect to the stock intermediate pipe? By the time you put LT's on, with a catted Y-pipe, you have used up a lot of real estate under the car. And a cutout would add a few inches more to the setup. But it really makes no sense at all to spend money on long tubes, high flow cats, and a Y-pipe, and then try to force the exhaust through the stock 2.75" crimp-bent intermediate pipe. Sure, you have a cutout.... but are you going to drive around with it open all the time? If you can get away without a ticket for excessive noise, are you sure you want to damage your hearing with all that constant racket entering the passenger compartment? My hearing is seriously damaged by loud cars and loud concerts.... sure, I'm older than dirt, but hearing loss is really not a lot of fun, no matter how old you are.
I know for many years Old Bridge Raceway Park here in NJ would not allow open exhaust of any kind except on Sundays (and NHRA events). I replace the cats with Borla XR1 mufflers, and the straight pipes, and had to angle the turndowns back by the axle inwards, to try and keep the noise under the car, to beat the sound meters in techj, and on the starting line. Then they realized what people were doing, and added a spec that required mufflers with at least 4 baffles. That's when I stopped going there.
A 3" catback will pick up maybe 10HP over the stock 2.75" system, even on a pure stock engine. That HP will be nice to have, when you are cruising with the cutout closed, and want to have some fun. I guess you could go with an electric cutout.
04-19-2017, 08:57 PM
#9
Registered User
Join Date: Jan 2010
Location: Philadelphia, PA
Posts: 34
Re: Info on x-Pipe, Cats? True duals? Help!!
Don't worry about hijacking, the Thread Staarter hasn't signed into this site since his last post above, 2 years ago.
You have to check the specific rules for emissions inspection. Technically, long tube headers can never be emissions legal on an LT1 car. Federal law prohibits changing the number of cats on the car, or changing the location of the cats. Long tube move the cats back from their original location. Not all states enforce Federal law. California does, don't know about urban Pennsylvania. Friends living in rural PA seem to have little in the way of inspections. Then, does PA require CARB-EO certification on aftermarket performance parts? For headers, that's a metal tag, welded to a primary, with the CARB-EO certification number on it. Long tubes can't get that because of Federal law.
But, many jurisdictions really don't care as long as your car passes the tailpipe test, PCM has no codes, and the car has cats. You could have long tubes, a cat on each collector. 3" CarSound cats are good. I ran them on my custom Y-pipe. They were flanged and bolted so I could remove them at the track, because I trun highly leaded racing fuel, and lead does not play well with cats and O2 sensors. We checked it on a PA emissions dyno (engine was built in PA) and it passed NJ standards. But I never had it inspected in NJ, since it was pretty much limited to being a track car. Now in NJ, 95 and older to not have any inspections at all - no emissions, no safety - and no sticker.
Let's say you get long tubes, and a duel cat Y-pipe. First question is will that Y-pipe even connect to the stock intermediate pipe? By the time you put LT's on, with a catted Y-pipe, you have used up a lot of real estate under the car. And a cutout would add a few inches more to the setup. But it really makes no sense at all to spend money on long tubes, high flow cats, and a Y-pipe, and then try to force the exhaust through the stock 2.75" crimp-bent intermediate pipe. Sure, you have a cutout.... but are you going to drive around with it open all the time? If you can get away without a ticket for excessive noise, are you sure you want to damage your hearing with all that constant racket entering the passenger compartment? My hearing is seriously damaged by loud cars and loud concerts.... sure, I'm older than dirt, but hearing loss is really not a lot of fun, no matter how old you are.
I know for many years Old Bridge Raceway Park here in NJ would not allow open exhaust of any kind except on Sundays (and NHRA events). I replace the cats with Borla XR1 mufflers, and the straight pipes, and had to angle the turndowns back by the axle inwards, to try and keep the noise under the car, to beat the sound meters in techj, and on the starting line. Then they realized what people were doing, and added a spec that required mufflers with at least 4 baffles. That's when I stopped going there.
A 3" catback will pick up maybe 10HP over the stock 2.75" system, even on a pure stock engine. That HP will be nice to have, when you are cruising with the cutout closed, and want to have some fun. I guess you could go with an electric cutout.
You have to check the specific rules for emissions inspection. Technically, long tube headers can never be emissions legal on an LT1 car. Federal law prohibits changing the number of cats on the car, or changing the location of the cats. Long tube move the cats back from their original location. Not all states enforce Federal law. California does, don't know about urban Pennsylvania. Friends living in rural PA seem to have little in the way of inspections. Then, does PA require CARB-EO certification on aftermarket performance parts? For headers, that's a metal tag, welded to a primary, with the CARB-EO certification number on it. Long tubes can't get that because of Federal law.
But, many jurisdictions really don't care as long as your car passes the tailpipe test, PCM has no codes, and the car has cats. You could have long tubes, a cat on each collector. 3" CarSound cats are good. I ran them on my custom Y-pipe. They were flanged and bolted so I could remove them at the track, because I trun highly leaded racing fuel, and lead does not play well with cats and O2 sensors. We checked it on a PA emissions dyno (engine was built in PA) and it passed NJ standards. But I never had it inspected in NJ, since it was pretty much limited to being a track car. Now in NJ, 95 and older to not have any inspections at all - no emissions, no safety - and no sticker.
Let's say you get long tubes, and a duel cat Y-pipe. First question is will that Y-pipe even connect to the stock intermediate pipe? By the time you put LT's on, with a catted Y-pipe, you have used up a lot of real estate under the car. And a cutout would add a few inches more to the setup. But it really makes no sense at all to spend money on long tubes, high flow cats, and a Y-pipe, and then try to force the exhaust through the stock 2.75" crimp-bent intermediate pipe. Sure, you have a cutout.... but are you going to drive around with it open all the time? If you can get away without a ticket for excessive noise, are you sure you want to damage your hearing with all that constant racket entering the passenger compartment? My hearing is seriously damaged by loud cars and loud concerts.... sure, I'm older than dirt, but hearing loss is really not a lot of fun, no matter how old you are.
I know for many years Old Bridge Raceway Park here in NJ would not allow open exhaust of any kind except on Sundays (and NHRA events). I replace the cats with Borla XR1 mufflers, and the straight pipes, and had to angle the turndowns back by the axle inwards, to try and keep the noise under the car, to beat the sound meters in techj, and on the starting line. Then they realized what people were doing, and added a spec that required mufflers with at least 4 baffles. That's when I stopped going there.
A 3" catback will pick up maybe 10HP over the stock 2.75" system, even on a pure stock engine. That HP will be nice to have, when you are cruising with the cutout closed, and want to have some fun. I guess you could go with an electric cutout.
I was reading that it can be an issue getting the exhaust to run behind the axle and a lot of people just end it before the axle. I have never had so many issues figuring out an exhaust for a car before, too many options with these cars!
04-20-2017, 11:07 AM
#10
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Join Date: Nov 1998
Location: Hell was full so they sent me to NJ
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Re: Info on x-Pipe, Cats? True duals? Help!!
If you are using a Y-pipe and a 3" catback, the intermediate pipe follows the stock path over the rear axle, uses the stock hangers for the muffler. The picture above of the 4" Mufflex catback is my car. Tight fit, but even the 4" system fit over the axle with no problem.
You only have a problem going over the rear axle with "true duals".... two pipes, one for each side of the exhaust. Some people route both pipes together over the axle in the stock location. May be an issue with the panhard rod upper brace. Or they run the passenger side pipe in the stock location, and the driver side pipe over the other (left) side of the axle. Pretty sure you need a panhard rod relocation kit for that.
Correct - you need:
- long tube headers
- upgraded header to head gaskets
- upgraded head flange bolts
- y-pipe, with or without cats
- 3" catback
A muffler shop may be required to fit the end of the y-pipe to the catback intermediate pipe.
One other issue that hasn't been mentioned - is your suspension lowered? If so, ground clearance between the driver's side headersy-pipe may be very tight.
You only have a problem going over the rear axle with "true duals".... two pipes, one for each side of the exhaust. Some people route both pipes together over the axle in the stock location. May be an issue with the panhard rod upper brace. Or they run the passenger side pipe in the stock location, and the driver side pipe over the other (left) side of the axle. Pretty sure you need a panhard rod relocation kit for that.
Correct - you need:
- long tube headers
- upgraded header to head gaskets
- upgraded head flange bolts
- y-pipe, with or without cats
- 3" catback
A muffler shop may be required to fit the end of the y-pipe to the catback intermediate pipe.
One other issue that hasn't been mentioned - is your suspension lowered? If so, ground clearance between the driver's side headersy-pipe may be very tight.
Last edited by Injuneer; 04-20-2017 at 02:25 PM.
04-20-2017, 12:46 PM
#11
Registered User
Join Date: Jan 2010
Location: Philadelphia, PA
Posts: 34
Re: Info on x-Pipe, Cats? True duals? Help!!
If you are using a Y-pipe and a 3" catback, the intermediate pipe follows the stock path over the rear axle, uses the stock hangers for the muffler. The picture above of the 4" Mufflex catback is my car. Tight fit, but even the 4" system fit over the axle with no problem.
You only have a problem going over the rear axle with "true duals".... two pipes, one for each side of the exhaust. Some people route both pipes together over the axle in the stock location. May be an issue with the panhard rod upper brace. Or they run the passenger side pipe in the stock location, and the driver side pipe over the other (left) side of the axle. Pretty sure you need a panhard rod relocation kit for that.
Correct - you need:
- long tube headers
- upgraded header to head gaskets
- upgraded head flange bolts
- y-pipe, with or without cars
- 3" catback
A muffler shop may be required to fit the end of the y-pipe to the catback intermediate pipe.
One other issue that hasn't been mentioned - is your suspension lowered? If so, ground clearance between the driver's side headersy-pipe may be very tight.
You only have a problem going over the rear axle with "true duals".... two pipes, one for each side of the exhaust. Some people route both pipes together over the axle in the stock location. May be an issue with the panhard rod upper brace. Or they run the passenger side pipe in the stock location, and the driver side pipe over the other (left) side of the axle. Pretty sure you need a panhard rod relocation kit for that.
Correct - you need:
- long tube headers
- upgraded header to head gaskets
- upgraded head flange bolts
- y-pipe, with or without cars
- 3" catback
A muffler shop may be required to fit the end of the y-pipe to the catback intermediate pipe.
One other issue that hasn't been mentioned - is your suspension lowered? If so, ground clearance between the driver's side headersy-pipe may be very tight.
The car is not currently lowered but I was considering purchasing lowering springs. Is there a limit to how much I should lower it if I go that route?
I also read that some people recommend replacing the Engine Mounts with new Polyurethane ones while they are doing the header install. What are your thoughts on this, is it necessary?
EDIT: I have been looking into the SLP Loudmouth and I keep seeing that they are only for 98-02. Will it not fit on LT1's?
Last edited by Longwell; 04-20-2017 at 12:55 PM.
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