Dual exhaust set up/ route

[p24-1953]

What is the best set up for a dual exhaust. 

1.)True dual all the way back? 

2.) 2 into the muffler?

3.) Duals with a crossover pipe?

[Don Coatney]

I ran true dual exhaust with no interconnecting cross over pipe. I am not saying this is the best way to do it. But this is how I did it. Others may have different opinions.

[52 work truck]

true duals on my pickup

[casper50]

 on my 47 coupe  Mine would not go under the driveshaft as Don's does.  Would have made them to close to the ground.

 

Edited November 25, 2017 by casper50

[MarkAubuchon]

Both of my cars have duals all the way back.  Mine looks like Don C.  Two things to consider 1. Sound I used mufflers and placed them behind the drivers seat and as close as the rear end as possible to minimize cab noise. 2. Exit of the car tail pipes do you want them seperate or side by side.

[55 Fargo]

8 hours ago, casper50 said:

 on my 47 coupe  Mine would not go under the driveshaft as Don's does.  Would have made them to close to the ground.

 

Is that Grace Slick and JA "somebody to love" song in background?

Almost felt like lighting up a legal bought reefer man.....lol

But I dont smoke weed....

This is when i first installed the mufflers and whatever pipe i had handy it needs to be done properly yet

 

Edited November 25, 2017 by 55 Fargo Spitfire

[blucarsdn]

Many years ago, like sixty plus, I ran a custom exhaust shop in Eastern Idaho, inline engines were more common than V8's so the majority of our business was splitting manifolds. I have built split manifolds for just about every make and model of engine there every was. The fact of the  matter is that a split manifold on an inline engine does nothing for an engine except create noise, which leads one to believe that the engine is making more power.

We built our own split manifolds, and as a general rule did not remove the heat riser. We would insert a plate through the heat riser and tack weld it in place, then cut a whole in the side we had blocked off to attach a flange affair for the new pipe to attach to. As a general rule we would use mufflers on both pipes to minimize the "rap/cackle" that inline engines can produce.

Headers were not very popular on inline engines because they very expensive and they did not work well in cold weather due to the lack of a heat riser. 

[55 Fargo]

6 hours ago, blucarsdn said:

Many years ago, like sixty plus, I ran a custom exhaust shop in Eastern Idaho, inline engines were more common than V8's so the majority of our business was splitting manifolds. I have built split manifolds for just about every make and model of engine there every was. The fact of the  matter is that a split manifold on an inline engine does nothing for an engine except create noise, which leads one to believe that the engine is making more power.

We built our own split manifolds, and as a general rule did not remove the heat riser. We would insert a plate through the heat riser and tack weld it in place, then cut a whole in the side we had blocked off to attach a flange affair for the new pipe to attach to. As a general rule we would use mufflers on both pipes to minimize the "rap/cackle" that inline engines can produce.

Headers were not very popular on inline engines because they very expensive and they did not work well in cold weather due to the lack of a heat riser. 

Ive heard this type of nonsense  on this topic before.

Splitting the exhaust does nothing but make noise did you mention this to your customers?

Allowing these engine to breath certainly helps its not adding a blower or nitrous i will agree.

I do realize many are looking for that sound and look of tru duals and are not fixated on more power.

If you build these engines with dual or tri carb intakes, high lift cam, more compression via an aftermarket head or milling stock types having a stock 1 dump exhaust would be like shooting yourself in the foot.

You obviously did not or have not built hi perf Chrysler flathead 

But to make a blanket statement duals only make noise and no added power however slight that might be sounds ridiculous....

Edited November 28, 2017 by 55 Fargo Spitfire
Softened the approach

[John-T-53]

Countdown in.....5....4....3....

 

[Ajgkirkwood]

Lol. However in logical light. A dual header would allow it to breath better. Because of the design of the stock header. 5 and 6 breath well due to it going straight down the header. 1 and 2 suffer because its chocked off 

[chrysler1941]

So dual exhaust on a stock flat 6 will do what besides higher gas consumption? 

[55 Fargo]

48 minutes ago, chrysler1941 said:

So dual exhaust on a stock flat 6 will do what besides higher gas consumption? 

Can you please explain?

Or does this mean more peddle to the meddle causality?

At any rate i can firmly attest to improved fuel economy with dual carbs and exhaust as will many others.

Although fuel economy is important it is not a means to an end with these type of vehicles.

I can state emphatically with multi carbs dual exhaust and an overdrive or a decent final drive ratio fuel economy is very decent and is better than a 1 carb and exhaust with poor gearing..

 

Edited November 28, 2017 by 55 Fargo Spitfire

[Adam H P15 D30]

1 hour ago, chrysler1941 said:

So dual exhaust on a stock flat 6 will do what besides higher gas consumption? 

The Mopar Flathead 6 and other makes of straight 6's suffer a major flaw when it comes to fuel distribution and exhaust.  With the single carb in the middle, the center 2 cylinders receive a lot of fuel while the outer cylinders receive less.  The fact that 2 carbs are placed evenly between the 3 intake ports is why many see an improvement in performance and fuel economy.

Looking at a stock exhaust manifold speaks for itself.  The farthest cylinders from the exit suffer the most.  Any way to minimize that distance will help.

FWIW,

Adam

[55 Fargo]

47 minutes ago, Adam H P15 D30 said:

The Mopar Flathead 6 and other makes of straight 6's suffer a major flaw when it comes to fuel distribution and exhaust.  With the single carb in the middle, the center 2 cylinders receive a lot of fuel while the outer cylinders receive less.  The fact that 2 carbs are placed evenly between the 3 intake ports is why many see an improvement in performance and fuel economy.

Looking at a stock exhaust manifold speaks for itself.  The farthest cylinders from the exit suffer the most.  Any way to minimize that distance will help.

FWIW,

Adam

Thanks Adam not sure why so many think adding carbs or split echaust does nothing or sucks fuel.

Tim Kingsbury explains it well The Chrysler corp designed an engine for production costs and effiency for its normal use.

Now max power and efficiency via multi carbs and exhaust costs money and lowers profit which of course lowers the bottom line.

Now for the 265 and 250 big trucks you could order a factory dual carb and tru split header. WAS THAT JUST FOR LOOKS AND NOISE? 

I dont think so it added horsepower and torque.

The 265 and the early V8 had matched horsepower or close in the big truck line up.

 

[55 Fargo]

We all need to "Chill" yall dig...

Listen to my 60s song of the day, and grab a favorite beverage and enjoy...

Yall from down south care to share what this "polk salad" might be...

 

[casper50]

https://delishably.com/vegetable-dishes/Poke-Sallet-Poke-Salad-Recipe-How-to-Handle-Harvest-and-Prepare-the-Poisonous-Pokeweed

[55 Fargo]

11 minutes ago, casper50 said:

https://delishably.com/vegetable-dishes/Poke-Sallet-Poke-Salad-Recipe-How-to-Handle-Harvest-and-Prepare-the-Poisonous-Pokeweed

Thanks apparently it grows in my locale in the delta marshy swampy areas...

[Los_Control]

6 hours ago, chrysler1941 said:

So dual exhaust on a stock flat 6 will do what besides higher gas consumption? 

the old 4 and 2, is pretty easy on the flat 6 dodge, pull the plate on the bottom and add a divider then put the plate back on, easy peasy 5 min job  ... dont forget to add a new exhaust pipe to the manifold. Will have one pipe connected to 2 cylinders and other to 4 cylinders.

It is the sound you get out of the dual exhaust, some of those old chebby 292 split with straight pipes could break store windows.

Now I never heard of a flat six dodge mis-behaving like that, maybe rattle a few windows but not break them.

 

Seems to me, with better flow you would gain more horse power and actually use less gas, pretty sure it is the smiles per mile that get counted in the end.

Far as routing goes, could cut both straight pipes over to drivers side and exit in front of rear wheel.

Roll that window down and rest your arm on the door, and smile all the way down the road listening to those pipes crackle!

[chrysler1941]

7 hours ago, 55 Fargo Spitfire said:

Can you please explain?

Or does this mean more peddle to the meddle causality?

At any rate i can firmly attest to improved fuel economy with dual carbs and exhaust as will many others.

Although fuel economy is important it is not a means to an end with these type of vehicles.

I can state emphatically with multi carbs dual exhaust and an overdrive or a decent final drive ratio fuel economy is very decent and is better than a 1 carb and exhaust with poor gearing..

 

No it's an honest question. As far as I know,  engine needs back pressure to limit unnecessary fuel flow. 

I can imagine dual exhaust will raise fuel consumption on a stock engine.

I'm sure with several carbs, another cam etc it's an advantage.

Edited November 28, 2017 by chrysler1941

[chrysler1941]

7 hours ago, Adam H P15 D30 said:

The Mopar Flathead 6 and other makes of straight 6's suffer a major flaw when it comes to fuel distribution and exhaust.  With the single carb in the middle, the center 2 cylinders receive a lot of fuel while the outer cylinders receive less.  The fact that 2 carbs are placed evenly between the 3 intake ports is why many see an improvement in performance and fuel economy.

Looking at a stock exhaust manifold speaks for itself.  The farthest cylinders from the exit suffer the most.  Any way to minimize that distance will help.

FWIW,

Adam

Sounds reasonable. Thanks for explaining.

[55 Fargo]

24 minutes ago, chrysler1941 said:

No it's an honest question. As far as I know,  engine needs back pressure to limit unnecessary fuel flow. 

I can imagine dual exhaust will raise fuel consumption on a stock engine.

I'm sure with several carbs, another cam etc it's an advantage.

Dont think this the case at all.

Now if you have single exhaust great and all is well keep it that way.

Im not sure you understand optimal exhaust flow and back pressure.

Engine think giant vaccum pump more in more out optimal breathing as in inhaling and exhaling. 

Let me put it this way these Lhead engines are asthmatic and help to allow flow makes it breath better.

You dont need multi carbs or a cam job necessarily to benefit from dual exhaust.

Look if you have your engine running well bone stock all.must be right in your world.

I just dont care for bone stock.....

[DrDoctor]

   If I remember my physics, the cross-over pipe is used to balance the exhaust pulses from the separate banks of a V-8 engine. Since the inline-6 cylinder has only one bank, the use of a cross-over pipe becomes redundant, and unnecessary (I think . . .).

[55 Fargo]

56 minutes ago, DrDoctor said:

   If I remember my physics, the cross-over pipe is used to balance the exhaust pulses from the separate banks of a V-8 engine. Since the inline-6 cylinder has only one bank, the use of a cross-over pipe becomes redundant, and unnecessary (I think . . .).

Some still add a cross over pipe into the equation.

They purport a reduced "rap" and a more mellow tone.

Although an inline 6 cylinder engine is not divisive as a V8s separated cylinder banks the inline with tru dual exhaust has 2 individual outlets purging 3 cylinders a piece.

In conclusion to the insinuated statement that dual exhaust on a stock inline 6 cylinder engine only perpetuates "noise and fuel consumption" is based on assumed beliefs rather than emperical evidence...

Edited November 29, 2017 by 55 Fargo Spitfire

[55 Fargo]

On 27/11/2017 at 4:38 PM, John-T-53 said:

Countdown in.....5....4....3....

 

Yup good product

[Ajgkirkwood]

When it was explained to me. The stock setup for fuel/air favors cyl 3 and 4 as its right in line. 1,2 and 5,6 get less. Now look at the exhaust. 5 and 6 have the best flow. 3 and 4 get kinda blocked off and 1 and 2 hit a back pressure wall. So if 1 and 2 get less fuel from the start and the back pressure from the exhaust does nothing to help... Your almost running a 4 cly