Dual Cat is good because usually it gives more surface are and less back pressure, same thing for dual mufflers. The center-pipe could be a single pipe of large diameter and work ok vs dual pipes all the way back. And as was mentioned a balance tube helps power- x-tube, h-pipe.
Degrees of Dual Exhaust
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An X pipe is a great trick.
My car has shorty headers, 2 7/8 inch piping to dual cats, then an x pipe, then a huge center muffler that is just two combined as one unit, then 2 resonators at the exits.
Very effective (quiet) until you get on it, then it has just enough bark to let you know that the throttle is open. Proven over the years to be efficient all the way to around 600 hp.
Packaging issues dictate the exhausts you can use under any car.
My car has shorty headers, 2 7/8 inch piping to dual cats, then an x pipe, then a huge center muffler that is just two combined as one unit, then 2 resonators at the exits.
Very effective (quiet) until you get on it, then it has just enough bark to let you know that the throttle is open. Proven over the years to be efficient all the way to around 600 hp.
Packaging issues dictate the exhausts you can use under any car.
Originally Posted By: OVERKILL
Originally Posted By: Jarlaxle
Originally Posted By: jdawg89
I hate cats and mufflers. They get In the way and restrict flow
My wife is making 900HP through a catalyst. Yer full of it!
What in the flying *bleep* is SHE rockin?
Just a little V6!
OK, a big (272ci) V6. And about 20psi of boost. (It's a Grand National.)
Originally Posted By: Jarlaxle
Originally Posted By: jdawg89
I hate cats and mufflers. They get In the way and restrict flow
My wife is making 900HP through a catalyst. Yer full of it!
What in the flying *bleep* is SHE rockin?
Just a little V6!
OK, a big (272ci) V6. And about 20psi of boost. (It's a Grand National.)
Our Equinox has #4. Single pipe to back, muffler, and two outputs.
The only real downside with the setup is that the 3.0L Doesn't really move enough hot air to warm it up. In cold weather, even after long highway trips, at idle and slow speeds still condenses out the exhaust. It looks good, but isn't functional. Personally on a car like my focus, I like the plain single exhaust.
Now, I recall seeing somewhere a whle back that if you have a V8, you don't want true dual exhaust. A single exhaust will provide better performance, because V8 engines exhaust are in pulses, and a single exhaust helps keep the flow and backpressure up. Or something like that.
Also no exhaust at all, no cats or mufflers, seems to give problems with hard starting in cold weather due to lack of backpressure. A lot of engines perform better with some backpressure. versus no backpressure. Similar to how a lot of 2 stroke engines won't even operate without a resonator to provide backpressure.
The only real downside with the setup is that the 3.0L Doesn't really move enough hot air to warm it up. In cold weather, even after long highway trips, at idle and slow speeds still condenses out the exhaust. It looks good, but isn't functional. Personally on a car like my focus, I like the plain single exhaust.
Now, I recall seeing somewhere a whle back that if you have a V8, you don't want true dual exhaust. A single exhaust will provide better performance, because V8 engines exhaust are in pulses, and a single exhaust helps keep the flow and backpressure up. Or something like that.
Also no exhaust at all, no cats or mufflers, seems to give problems with hard starting in cold weather due to lack of backpressure. A lot of engines perform better with some backpressure. versus no backpressure. Similar to how a lot of 2 stroke engines won't even operate without a resonator to provide backpressure.
Originally Posted By: Nick R
Our Equinox has #4. Single pipe to back, muffler, and two outputs.
The only real downside with the setup is that the 3.0L Doesn't really move enough hot air to warm it up. In cold weather, even after long highway trips, at idle and slow speeds still condenses out the exhaust. It looks good, but isn't functional. Personally on a car like my focus, I like the plain single exhaust.
Now, I recall seeing somewhere a whle back that if you have a V8, you don't want true dual exhaust. A single exhaust will provide better performance, because V8 engines exhaust are in pulses, and a single exhaust helps keep the flow and backpressure up. Or something like that.
Also no exhaust at all, no cats or mufflers, seems to give problems with hard starting in cold weather due to lack of backpressure. A lot of engines perform better with some backpressure. versus no backpressure. Similar to how a lot of 2 stroke engines won't even operate without a resonator to provide backpressure.
Even a SINGLE exhausts in pulses. GM for years has had a corporate policy of one cat per car. Beware of serpent car salesmen who will tell you that one pipe is better than two. One of the main problems, outside of not cheaping out on converters, of a dual system is noise, crossover pipes reduct the rap and are required to meet noise standards. Cheaper to use one pipe and a phony "Y" in the back. If ya gonna use a mingy "Y", at least paint the pipes black so those of us behind you can't see the silly "dual" pipes.
Our Equinox has #4. Single pipe to back, muffler, and two outputs.
The only real downside with the setup is that the 3.0L Doesn't really move enough hot air to warm it up. In cold weather, even after long highway trips, at idle and slow speeds still condenses out the exhaust. It looks good, but isn't functional. Personally on a car like my focus, I like the plain single exhaust.
Now, I recall seeing somewhere a whle back that if you have a V8, you don't want true dual exhaust. A single exhaust will provide better performance, because V8 engines exhaust are in pulses, and a single exhaust helps keep the flow and backpressure up. Or something like that.
Also no exhaust at all, no cats or mufflers, seems to give problems with hard starting in cold weather due to lack of backpressure. A lot of engines perform better with some backpressure. versus no backpressure. Similar to how a lot of 2 stroke engines won't even operate without a resonator to provide backpressure.
Even a SINGLE exhausts in pulses. GM for years has had a corporate policy of one cat per car. Beware of serpent car salesmen who will tell you that one pipe is better than two. One of the main problems, outside of not cheaping out on converters, of a dual system is noise, crossover pipes reduct the rap and are required to meet noise standards. Cheaper to use one pipe and a phony "Y" in the back. If ya gonna use a mingy "Y", at least paint the pipes black so those of us behind you can't see the silly "dual" pipes.
Originally Posted By: Nick R
Our Equinox has #4. Single pipe to back, muffler, and two outputs.
The only real downside with the setup is that the 3.0L Doesn't really move enough hot air to warm it up. In cold weather, even after long highway trips, at idle and slow speeds still condenses out the exhaust. It looks good, but isn't functional. Personally on a car like my focus, I like the plain single exhaust.
Now, I recall seeing somewhere a whle back that if you have a V8, you don't want true dual exhaust. A single exhaust will provide better performance, because V8 engines exhaust are in pulses, and a single exhaust helps keep the flow and backpressure up. Or something like that.
Also no exhaust at all, no cats or mufflers, seems to give problems with hard starting in cold weather due to lack of backpressure. A lot of engines perform better with some backpressure. versus no backpressure. Similar to how a lot of 2 stroke engines won't even operate without a resonator to provide backpressure.
Must be why all those race cars use mufflers.
Our Equinox has #4. Single pipe to back, muffler, and two outputs.
The only real downside with the setup is that the 3.0L Doesn't really move enough hot air to warm it up. In cold weather, even after long highway trips, at idle and slow speeds still condenses out the exhaust. It looks good, but isn't functional. Personally on a car like my focus, I like the plain single exhaust.
Now, I recall seeing somewhere a whle back that if you have a V8, you don't want true dual exhaust. A single exhaust will provide better performance, because V8 engines exhaust are in pulses, and a single exhaust helps keep the flow and backpressure up. Or something like that.
Also no exhaust at all, no cats or mufflers, seems to give problems with hard starting in cold weather due to lack of backpressure. A lot of engines perform better with some backpressure. versus no backpressure. Similar to how a lot of 2 stroke engines won't even operate without a resonator to provide backpressure.
Must be why all those race cars use mufflers.
Abarth was using Y pipes in the 60s on some of their Volvo I 4 "upgrades". It's very difficult to come up with a cost effective dual system for transverse mounted "V" engines, but that's no excuse for the Camaro and Corvette.
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Among new car buiders, Nissan has some fine sounding V6 exhaust systems. I don't know quite how they do it. Anybody look underneath a new Z?
Old time machanics will remember when many V8 dual systems came with a manifold valve which sent all the exhaust to ONE side during warmup. Of course they stuck the same way " mainfold heat control valves" stuck, usually closed.
Originally Posted By: Jarlaxle
Originally Posted By: jdawg89
I hate cats and mufflers. They get In the way and restrict flow
My wife is making 900HP through a catalyst. Yer full of it!
The Summit Racing catalog is FULL of high flow cats for such purposes, if you are using the factory cat YOU are full of it.
Originally Posted By: jdawg89
I hate cats and mufflers. They get In the way and restrict flow
My wife is making 900HP through a catalyst. Yer full of it!
The Summit Racing catalog is FULL of high flow cats for such purposes, if you are using the factory cat YOU are full of it.
OVERKILL
$100 Site Donor 2021
Originally Posted By: Jarlaxle
Originally Posted By: OVERKILL
Originally Posted By: Jarlaxle
Originally Posted By: jdawg89
I hate cats and mufflers. They get In the way and restrict flow
My wife is making 900HP through a catalyst. Yer full of it!
What in the flying *bleep* is SHE rockin?
Just a little V6!
OK, a big (272ci) V6. And about 20psi of boost. (It's a Grand National.)
Good 'ol BOOOOOOOOOOOST! I would have figured she'd be higher than 20psi to make that kind of HP though!
Originally Posted By: OVERKILL
Originally Posted By: Jarlaxle
Originally Posted By: jdawg89
I hate cats and mufflers. They get In the way and restrict flow
My wife is making 900HP through a catalyst. Yer full of it!
What in the flying *bleep* is SHE rockin?
Just a little V6!
OK, a big (272ci) V6. And about 20psi of boost. (It's a Grand National.)
Good 'ol BOOOOOOOOOOOST! I would have figured she'd be higher than 20psi to make that kind of HP though!
Originally Posted By: HerrStig
Old time machanics will remember when many V8 dual systems came with a manifold valve which sent all the exhaust to ONE side during warmup. Of course they stuck the same way " mainfold heat control valves" stuck, usually closed.
First thing you did was wire that sucker open!
Old time machanics will remember when many V8 dual systems came with a manifold valve which sent all the exhaust to ONE side during warmup. Of course they stuck the same way " mainfold heat control valves" stuck, usually closed.
First thing you did was wire that sucker open!
Originally Posted By: HerrStig
Among new car buiders, Nissan has some fine sounding V6 exhaust systems. I don't know quite how they do it. Anybody look underneath a new Z?
The 370z has what probably classifies as an H-pipe, with two pipes coming off the engine that briefly join into one and then separate back to two going out to the back, but then they both go into the same muffler which has two tailpipes.
Among new car buiders, Nissan has some fine sounding V6 exhaust systems. I don't know quite how they do it. Anybody look underneath a new Z?
The 370z has what probably classifies as an H-pipe, with two pipes coming off the engine that briefly join into one and then separate back to two going out to the back, but then they both go into the same muffler which has two tailpipes.
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I'm kind of partial to single exhaust, or two tips coming out of one muffler, if an exhaust isn't one of the "true" duals, both out of simplicity and "mechanical honesty." That said, I love the look of quad outlets and my car has a single pipe coming from the headers, going through the turbo and into a catalyst, and then out to the back where it goes into a big muffler with two tips coming out each end. It may be "fake" but I'm not complaining about how it looks or sounds.
Originally Posted By: HerrStig
Originally Posted By: Nick R
Our Equinox has #4. Single pipe to back, muffler, and two outputs.
The only real downside with the setup is that the 3.0L Doesn't really move enough hot air to warm it up. In cold weather, even after long highway trips, at idle and slow speeds still condenses out the exhaust. It looks good, but isn't functional. Personally on a car like my focus, I like the plain single exhaust.
Now, I recall seeing somewhere a whle back that if you have a V8, you don't want true dual exhaust. A single exhaust will provide better performance, because V8 engines exhaust are in pulses, and a single exhaust helps keep the flow and backpressure up. Or something like that.
Also no exhaust at all, no cats or mufflers, seems to give problems with hard starting in cold weather due to lack of backpressure. A lot of engines perform better with some backpressure. versus no backpressure. Similar to how a lot of 2 stroke engines won't even operate without a resonator to provide backpressure.
Even a SINGLE exhausts in pulses. GM for years has had a corporate policy of one cat per car. Beware of serpent car salesmen who will tell you that one pipe is better than two. One of the main problems, outside of not cheaping out on converters, of a dual system is noise, crossover pipes reduct the rap and are required to meet noise standards. Cheaper to use one pipe and a phony "Y" in the back. If ya gonna use a mingy "Y", at least paint the pipes black so those of us behind you can't see the silly "dual" pipes.
Many dual exhausts have no crossover. My LT1 Caprices didn't and were some of the quietest cars I have ever driven!
Originally Posted By: Nick R
Our Equinox has #4. Single pipe to back, muffler, and two outputs.
The only real downside with the setup is that the 3.0L Doesn't really move enough hot air to warm it up. In cold weather, even after long highway trips, at idle and slow speeds still condenses out the exhaust. It looks good, but isn't functional. Personally on a car like my focus, I like the plain single exhaust.
Now, I recall seeing somewhere a whle back that if you have a V8, you don't want true dual exhaust. A single exhaust will provide better performance, because V8 engines exhaust are in pulses, and a single exhaust helps keep the flow and backpressure up. Or something like that.
Also no exhaust at all, no cats or mufflers, seems to give problems with hard starting in cold weather due to lack of backpressure. A lot of engines perform better with some backpressure. versus no backpressure. Similar to how a lot of 2 stroke engines won't even operate without a resonator to provide backpressure.
Even a SINGLE exhausts in pulses. GM for years has had a corporate policy of one cat per car. Beware of serpent car salesmen who will tell you that one pipe is better than two. One of the main problems, outside of not cheaping out on converters, of a dual system is noise, crossover pipes reduct the rap and are required to meet noise standards. Cheaper to use one pipe and a phony "Y" in the back. If ya gonna use a mingy "Y", at least paint the pipes black so those of us behind you can't see the silly "dual" pipes.
Many dual exhausts have no crossover. My LT1 Caprices didn't and were some of the quietest cars I have ever driven!
Originally Posted By: Jarlaxle
Originally Posted By: jdawg89
I hate cats and mufflers. They get In the way and restrict flow
My wife is making 900HP through a catalyst. Yer full of it!
Holy [censored]! Well I'm kinda referring to pulling a cat off of a stock vehicle. You'll notice a difference
Originally Posted By: jdawg89
I hate cats and mufflers. They get In the way and restrict flow
My wife is making 900HP through a catalyst. Yer full of it!
Holy [censored]! Well I'm kinda referring to pulling a cat off of a stock vehicle. You'll notice a difference
My Trans Am GTA 87 had a y-pipe to a single muffler, then two tail pipes. Just didnt make sense.
Then I got into Mustangs and it seems like it's all better now, lol.
Then I got into Mustangs and it seems like it's all better now, lol.
I'm not sure why it really matters anyway, other than an interesting discussion of different types. Some people I know like to get into urination contests over whose car has "true" this or "true" that. To me, what matters is what works.
The F-bodies were interesting. Some of the G-bodies had the same type of setup, especially the Grand National. It had a transverse rear muffler with an outlet on each side. I converted my '84 Cutlass from single outlet to dual outlet using an Edelbrock muffler for a Grand National. Later on, I put an exhaust system from a 442 on it, which split right after the catalytic converter into two very small mufflers/resonators, then two pipes over the axle and out. The Monte Carlo SS used the same setup.
We had two Cadillacs with fake duals (single pipe that Y'd into two rear mufflers). Our Acura MDX has the same fake dual setup. It must help some, as the '04 MDX was the first to use the two rear mufflers and it got a 15 hp boost over the '03 MDX, which used a single rear muffler. A GM powertrain engineer explained it like this: if you use two mufflers in the back, you can make them much less restrictive without an increase in the noise level, since each only processes half the flow. So there apparently IS an engineering reasoning behind using two mufflers from a single main pipe.
The F-bodies were interesting. Some of the G-bodies had the same type of setup, especially the Grand National. It had a transverse rear muffler with an outlet on each side. I converted my '84 Cutlass from single outlet to dual outlet using an Edelbrock muffler for a Grand National. Later on, I put an exhaust system from a 442 on it, which split right after the catalytic converter into two very small mufflers/resonators, then two pipes over the axle and out. The Monte Carlo SS used the same setup.
We had two Cadillacs with fake duals (single pipe that Y'd into two rear mufflers). Our Acura MDX has the same fake dual setup. It must help some, as the '04 MDX was the first to use the two rear mufflers and it got a 15 hp boost over the '03 MDX, which used a single rear muffler. A GM powertrain engineer explained it like this: if you use two mufflers in the back, you can make them much less restrictive without an increase in the noise level, since each only processes half the flow. So there apparently IS an engineering reasoning behind using two mufflers from a single main pipe.
Originally Posted By: SteveSRT8
Originally Posted By: HerrStig
Old time machanics will remember when many V8 dual systems came with a manifold valve which sent all the exhaust to ONE side during warmup. Of course they stuck the same way " mainfold heat control valves" stuck, usually closed.
First thing you did was wire that sucker open!
My '84 Cutlass had something similar (but different). The left side manifold went down into a crossover pipe, which went under the oil pan and connected to the right side manifold and then into a single converter. Between the left side manifold and the crossover pipe was a valve which would close when cold. All the exhaust flow from the left side would be forced through a crossover port in the (aluminum) intake manifold. Talk about a performance-robber!
Originally Posted By: HerrStig
Old time machanics will remember when many V8 dual systems came with a manifold valve which sent all the exhaust to ONE side during warmup. Of course they stuck the same way " mainfold heat control valves" stuck, usually closed.
First thing you did was wire that sucker open!
My '84 Cutlass had something similar (but different). The left side manifold went down into a crossover pipe, which went under the oil pan and connected to the right side manifold and then into a single converter. Between the left side manifold and the crossover pipe was a valve which would close when cold. All the exhaust flow from the left side would be forced through a crossover port in the (aluminum) intake manifold. Talk about a performance-robber!
Originally Posted By: Jarlaxle
Originally Posted By: Colt45ws
Everything below #1 is hokey, IMO. My Mom's Fusion is setup like #2 or #3. Does absolutely nothing. If anything, you want less flow as it goes back to keep the velocity up as the gas cools and condenses.
My Magnum had a variation on that and it was functional: it had dual headpipes & cats, which went to a large single muffler (nicknamed the "suitcase" for good reason), then dual tailpipes. Many dual setups are fake, but not that one.
First fake duals I can think of was probably the 1982 F-body...no room for the second pipe!
The Magnum has the typical LX/LC car dual system- it sorta combines the balance tube with an oversized muffler. I'd say its "true dual."
Fake duals seemed to get really popular in the 80s and 90s. ALL those GM J-bodies and similar (Grand Ams, Grand Prixs, Cutlasses, Bonnevilles etc.) with the system pictured in the OP's original post! Yeah, sometimes some exhaust gasses did come rather weakly out of the second pipe, but sheesh. What a lot of extra metal to carry around for zero performance gain.
Originally Posted By: Colt45ws
Everything below #1 is hokey, IMO. My Mom's Fusion is setup like #2 or #3. Does absolutely nothing. If anything, you want less flow as it goes back to keep the velocity up as the gas cools and condenses.
My Magnum had a variation on that and it was functional: it had dual headpipes & cats, which went to a large single muffler (nicknamed the "suitcase" for good reason), then dual tailpipes. Many dual setups are fake, but not that one.
First fake duals I can think of was probably the 1982 F-body...no room for the second pipe!
The Magnum has the typical LX/LC car dual system- it sorta combines the balance tube with an oversized muffler. I'd say its "true dual."
Fake duals seemed to get really popular in the 80s and 90s. ALL those GM J-bodies and similar (Grand Ams, Grand Prixs, Cutlasses, Bonnevilles etc.) with the system pictured in the OP's original post! Yeah, sometimes some exhaust gasses did come rather weakly out of the second pipe, but sheesh. What a lot of extra metal to carry around for zero performance gain.
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