YACT: Dual exhaust on a V6?

[RagingBITCH]

Originally posted by: vr6

A true dual exhaust has each bank of cylinders on a seperate pipe. The headers, cats, mufflers, etc, are all seperate.

I doubt any of the new cars with dual exhausts are set up that way.

In a family sedan, yea. In a performance car it should be setup that way.

 

[MercenaryForHire]

Originally posted by: RagingBITCH

Originally posted by: vr6

A true dual exhaust has each bank of cylinders on a seperate pipe. The headers, cats, mufflers, etc, are all seperate.

I doubt any of the new cars with dual exhausts are set up that way.

In a family sedan, yea. In a performance car it should be setup that way.

I'd hope that any V8 is running true dual exhausts.

- M4H

 

[iamwiz82]

Originally posted by: MercenaryForHire

Originally posted by: RagingBITCH

Originally posted by: vr6

A true dual exhaust has each bank of cylinders on a seperate pipe. The headers, cats, mufflers, etc, are all seperate.

I doubt any of the new cars with dual exhausts are set up that way.

In a family sedan, yea. In a performance car it should be setup that way.

I'd hope that any V8 is running true dual exhausts.

- M4H

Most are crossover setups now. I believe the last Corvette to have a true dual was in the early 70s.

 

[JDub02]

Originally posted by: iamwiz82


Most are crossover setups now. I believe the last Corvette to have a true dual was in the early 70s.

Yah .. the reason is cost .. you only need 1 catalytic converter. A 3" pipe is just as good as 2 2.5" pipes. So the exhaust is just as efficient if you run a full 3" pipe from the headers, through the cat and into the muffler and have 2 2.5" outlets on the muffler to make a dual setup. This is what's on my truck now.


For a V6, a single 2.5" mandrel bent pipe will provide the optimum balance between airflow and backpressure. just make sure to get a good cat and muffler.

 

[JulesMaximus]

Originally posted by: theNEOone
my mazda6 has dual exhaust, me thinks it's not just twin tips. anyone want to confirm? i'll check later.

edit: yup, looks like dual exhaust

=|

Nope. It is a single exhaust.

If at any point between the exhaust manifolds and the tips at the rear of the car the two merge into one then you do not have true dual exhaust.

 

[JulesMaximus]

Originally posted by: thomsbrain

Originally posted by: Ketteringo

Originally posted by: toant103

Originally posted by: RaiderJ
I need some new exhaust on my S-10 Blazer, and someone recommended I go with dual exhaust. I was under the impression that dual exhaust on a V6 would be overkill, and maybe even reduce my backpressure so much as to hurt performace. I'm not really looking for anything obnoxious, just better than stock exhaust (nothing too loud, either).

Any suggestions from those more knowledgable than myself?

Accord V6 has dual exhaust

I'll vouch for that. I've got a '97 Accord EX V6 and it's got the dual exhaust.

As seen here: http://idonk.com/accord006.jpg

that's just cosmetic, there's only one muffler. i'm pretty sure the last generation (not the current ones) did have two mufflers though.

Probably one muffler and one resonator.

 

[RagingBITCH]

Originally posted by: JulesMaximus

Originally posted by: thomsbrain

Originally posted by: Ketteringo

Originally posted by: toant103

Originally posted by: RaiderJ
I need some new exhaust on my S-10 Blazer, and someone recommended I go with dual exhaust. I was under the impression that dual exhaust on a V6 would be overkill, and maybe even reduce my backpressure so much as to hurt performace. I'm not really looking for anything obnoxious, just better than stock exhaust (nothing too loud, either).

Any suggestions from those more knowledgable than myself?

Accord V6 has dual exhaust

I'll vouch for that. I've got a '97 Accord EX V6 and it's got the dual exhaust.

As seen here: http://idonk.com/accord006.jpg

that's just cosmetic, there's only one muffler. i'm pretty sure the last generation (not the current ones) did have two mufflers though.

Probably one muffler and one resonator.

6G Accords were a 2 muffler setup.

 

[JulesMaximus]

Originally posted by: MercenaryForHire

Originally posted by: RagingBITCH

Originally posted by: vr6

A true dual exhaust has each bank of cylinders on a seperate pipe. The headers, cats, mufflers, etc, are all seperate.

I doubt any of the new cars with dual exhausts are set up that way.

In a family sedan, yea. In a performance car it should be setup that way.

I'd hope that any V8 is running true dual exhausts.

- M4H

Most V8 cars have either an X or H pipe or are two into one and back into two pipes again.

 

[Demon-Xanth]

Dual is a bit more than is needed for that car.

One thing to remember: a single 3" is less restrictive than a dual 2".
A single 3" has about 7"^2 cross sectional area, each pipe in a 2" has 3.14"^2 for a total of about 6.28"^2. Air moves faster in the center of the pipe than on the outsides because of turbulance on the wall itself. A 3" pipe has 9.42" of surface area while each 2" pipe has 6.28" for a total of 12.56". So a single 3" is better off and often easier to route.

 

[PowerMac4Ever]

I recommend buying a dynomax super turbo muffler from summit for about $40 and have a shop weld it in for you.

 

[GasX]

My V6 SVT Contour has a quasi-dual exhaust system.

2.25 in. stainless steel pipes that are Y-spilt after the catalytic converter & the resonator into 2 mufflers with 2.5in exhaust tips.

The stock pipes on an SE V6 Contour are 2.0" true single exhaust.

 

[Howard]

Originally posted by: MercenaryForHire

Originally posted by: iamwiz82

Originally posted by: theNEOone

Originally posted by: fredtam

Originally posted by: Amused

Originally posted by: theNEOone
my mazda6 has dual exhaust, me thinks it's not just twin tips. anyone want to confirm? i'll check later.

edit: yup, looks like dual exhaust

=|

Looks to me like a single pipe seperates and goes to two mufflers. It's still a single exhaust.

Yep looks like a crossover pipe to single to dual after the converter.

oh, hmm. i thought dual exhaust meant two mufflers. so the technically correct definition of dual exhaust means that there should be two converters? (btw, i have no idea wth a converter is.)


=|

A true dual exhaust has each bank of cylinders on a seperate pipe. The headers, cats, mufflers, etc, are all seperate.

There's a guy with a Civic running four tips - two sets of two.

All cosmetic. Though personally I think it would be funnier if he actually ran four pipes to the back - the lack of backpressure would be hilarious.

- M4H

Let me say this for the billionth time - the less backpressure you have, the better.

 

[nakedfrog]

Originally posted by: Howard
Let me say this for the billionth time - the less backpressure you have, the better.

I seem to remember reading somewhere that it's only true to a certain extent.

 

[Nebor]

Originally posted by: nakedfrog

Originally posted by: Howard
Let me say this for the billionth time - the less backpressure you have, the better.

I seem to remember reading somewhere that it's only true to a certain extent.

Once you start modifying headers, THEN you should worry about backpressure. Anything past the headers is irrelevant.

 

[Howard]

Originally posted by: nakedfrog

Originally posted by: Howard
Let me say this for the billionth time - the less backpressure you have, the better.

I seem to remember reading somewhere that it's only true to a certain extent.

No, it's always true.

EDIT: I may be wrong. Check below.

 

[Howard]

Originally posted by: MercenaryForHire

Originally posted by: RagingBITCH

Originally posted by: vr6

A true dual exhaust has each bank of cylinders on a seperate pipe. The headers, cats, mufflers, etc, are all seperate.

I doubt any of the new cars with dual exhausts are set up that way.

In a family sedan, yea. In a performance car it should be setup that way.

I'd hope that any V8 is running true dual exhausts.

- M4H

Why? A single-tube exhaust is more efficient. More complex, I'll grant, but theoretically there's less heat loss through the exhaust system. Plus, with double the amount of cylinders firing into the same pipe, you can more effectively use the scavenging principle.

 

[Iron Woode]

Originally posted by: toant103

Originally posted by: RaiderJ
I need some new exhaust on my S-10 Blazer, and someone recommended I go with dual exhaust. I was under the impression that dual exhaust on a V6 would be overkill, and maybe even reduce my backpressure so much as to hurt performace. I'm not really looking for anything obnoxious, just better than stock exhaust (nothing too loud, either).

Any suggestions from those more knowledgable than myself?

Accord V6 has dual exhaust

So does the Buick GN/GNX.

 

[notfred]

Originally posted by: vr6

A true dual exhaust has each bank of cylinders on a seperate pipe. The headers, cats, mufflers, etc, are all seperate.[/quote]

I doubt any of the new cars with dual exhausts are set up that way.[/quote]

Why? The Ford Mustang is now and always has been set up that way.

 

[Vette73]

Originally posted by: Howard

Originally posted by: nakedfrog

Originally posted by: Howard
Let me say this for the billionth time - the less backpressure you have, the better.

I seem to remember reading somewhere that it's only true to a certain extent.

No, it's always true.

Ahh.. NO IT IS NOT.

I have worked on and built engines for cars, trucks, and even motorcycles. Changing the back pressure can have a big impact. Having to much bad, not enough for a street engine is also bad.

Easy example, take the muffler or even air filter off a motorcycle and see how well it runs.

 

[Squisher]

Originally posted by: Howard

Originally posted by: nakedfrog

Originally posted by: Howard
Let me say this for the billionth time - the less backpressure you have, the better.

I seem to remember reading somewhere that it's only true to a certain extent.

No, it's always true.

In the quarter mile, yes. But, you'll be screwing up the torque and hp curves so that it will not suit city driving. Driveability will suffer and changes to induction would be needed.

 

[Iron Woode]

Originally posted by: Marlin1975

Originally posted by: Howard

Originally posted by: nakedfrog

Originally posted by: Howard
Let me say this for the billionth time - the less backpressure you have, the better.

I seem to remember reading somewhere that it's only true to a certain extent.

No, it's always true.

Ahh.. NO IT IS NOT.

I have worked on and built engines for cars, trucks, and even motorcycles. Changing the back pressure can have a big impact. Having to much bad, not enough for a street engine is also bad.

Easy example, take the muffler or even air filter off a motorcycle and see how well it runs.

That's because you have just upset air/fuel ratio going into the engine.

 

[Iron Woode]

Originally posted by: Howard

Originally posted by: MercenaryForHire

Originally posted by: RagingBITCH

Originally posted by: vr6

A true dual exhaust has each bank of cylinders on a seperate pipe. The headers, cats, mufflers, etc, are all seperate.

I doubt any of the new cars with dual exhausts are set up that way.

In a family sedan, yea. In a performance car it should be setup that way.

I'd hope that any V8 is running true dual exhausts.

- M4H

Why? A single-tube exhaust is more efficient. More complex, I'll grant, but theoretically there's less heat loss through the exhaust system. Plus, with double the amount of cylinders firing into the same pipe, you can more effectively use the scavenging principle.

I am starting to think you don't know what you're talking about.

A good dual exhaust system is always more effecient.

My 1987 Ford Crown Vic has true dual exhaust and supposedly 10 more HP.

 

[Howard]

Originally posted by: Iron Woode

Originally posted by: Howard

Originally posted by: MercenaryForHire

Originally posted by: RagingBITCH

Originally posted by: vr6

A true dual exhaust has each bank of cylinders on a seperate pipe. The headers, cats, mufflers, etc, are all seperate.

I doubt any of the new cars with dual exhausts are set up that way.

In a family sedan, yea. In a performance car it should be setup that way.

I'd hope that any V8 is running true dual exhausts.

- M4H

Why? A single-tube exhaust is more efficient. More complex, I'll grant, but theoretically there's less heat loss through the exhaust system. Plus, with double the amount of cylinders firing into the same pipe, you can more effectively use the scavenging principle.

I am starting to think you don't know what you're talking about.

A good dual exhaust system is always more effecient.

My 1987 Ford Crown Vic has true dual exhaust and supposedly 10 more HP.

Can you tell me why?

Marlin1975, can you tell me what the definition of backpressure is?

 

[Vic]

Originally posted by: Howard

Originally posted by: nakedfrog

Originally posted by: Howard
Let me say this for the billionth time - the less backpressure you have, the better.

I seem to remember reading somewhere that it's only true to a certain extent.

No, it's always true.

I wouldn't say "always". A complete absence of backpressure could cause a reduction in low-end torque. It would also sound like sh!t with most engines, very loud and raspy. In other words, it might have more top-end hp, but it would be less streetable.

The idea of having a true dual exhaust is to make sure that none of the individual cylinder exhaust pulses interfere with each other. It has absolutely nothing to do with twin- or single-bank engines.
Breaking down various engines:
- In a 4 cylinder, the exhaust pulses are 180 degrees seperated from each other. The maximum possible length of each exhaust pulse is 180 degrees (real life is shorter, like 120 degrees, depending on numerous factors, like cam length and duration, individual to each engine design). Dual exhaust would provide absolutely no benefit.
- In a 6 cylinder, the exhaust pulses are 120 degrees seperated from each other. See above, minimal benefit if any. Same goes for rotaries, which also fire 3 times per revolution.
- In an 8 cylinder, the exhaust pulses are 90 degrees seperated from each other. And as V8's tend to fire a cylinder on one bank and then a cylinder on the other bank in firing order (this is not typical of all twin-bank engines, particularly boxer-4's, which fire 2 on one side then the 2 on the other side in order), dual exhaust would be very beneficial. As with any engine with even more cylinders.

 

[Howard]

Originally posted by: Vic

Originally posted by: Howard

Originally posted by: nakedfrog

Originally posted by: Howard
Let me say this for the billionth time - the less backpressure you have, the better.

I seem to remember reading somewhere that it's only true to a certain extent.

No, it's always true.

I wouldn't say "always". A complete absence of backpressure could cause a reduction in low-end torque. It would also sound like sh!t with most engines, very loud and raspy. In other words, it might have more top-end hp, but it would be less streetable.

The idea of having a true dual exhaust is to make sure that none of the individual cylinder exhaust pulses interfere with each other. It has absolutely nothing to do with twin- or single-bank engines.
Breaking down various engines:
- In a 4 cylinder, the exhaust pulses are 180 degrees seperated from each other. The maximum possible length of each exhaust pulse is 180 degrees (real life is shorter, like 120 degrees, depending on numerous factors, like cam length and duration, individual to each engine design). Dual exhaust would provide absolutely no benefit.
- In a 6 cylinder, the exhaust pulses are 120 degrees seperated from each other. See above, minimal benefit if any. Same goes for rotaries, which also fire 3 times per revolution.
- In an 8 cylinder, the exhaust pulses are 90 degrees seperated from each other. And as V8's tend to fire a cylinder on one bank and then a cylinder on the other bank in firing order (this is not typical of all twin-bank engines, particularly boxer-4's, which fire 2 on one side then the 2 on the other side in order), dual exhaust would be very beneficial. As with any engine with even more cylinders.

I'll backtrack a bit and say that backpressure is a necessary evil... but backpressure is not what allows maximum low-end torque.

I understand what you say about not having the exhaust pulses interfered with, but (assuming a single-pipe exhaust) as each pulse merges into the single pipe from the collectors of the exhaust headers (excuse me if my terminology is horrible), one of them should increase the velocity of the other, since an exhaust pulse has a low-pressure area directly behind it, right?

Or I could just be talking out of my ass since I haven't thought about this for over a year.