6.7 Twin Turbo Setup

[4EverBoosted1]

Lol, sorry

Looks like I got my answer from earlier!

 

[ChattyCathy]

Sorry but I am going to have to offer a rebuttal.

The fact that water transfers heat better than air is nothing new.

The air to water to air system uses air to cool air, with water as a medium between a the two. Ford went to this system to be able to regulate intake air temps better. Obviously there is no way at all to regulate a standard air to air intake temp.

You have the ability to transfer less heat because it is going from an air cooler, cooling a liquid (at a higher temp than the air, because the air cannot cool less than its own temp), then the liquid cools the charge air (to a temp that's higher than its own because it cannot physically cool less). Therefore you have the loss of heat transfer through an extra medium. The middleman alway takes his cut, if that makes sense. Throw in the heat soak from the added coolant capacity and lines and other various parts that warm up and stay hot. Then add it the heat from the trans and fuel system. There is no possible way that this system can work overall at a lower temp than a properly sized air to air at the same ambient temp.

I understand that the intercooler gets the priority of the cooler fluid. But it still doesn't matter, there are too many heat loads and heat soaked elements to ever out perform a standard air to air.

This is far from even being close to compared to a water to air that uses supercooled water (ice water) as a fluid medium to transfer heat.

Air to water to air (6.7) cooler systems have two distinct advantages; 1- they have the ability to regulate the intake temperature by a thermostatic valve, 2- they are smaller and can be made to also incorporate the cooling system for trans and fuel system.

However, a properly sized "air to water to air" system cannot physically ever out perform a properly sized air to air cooler in the real world for WOT charge air temps over a sustained duration.

And fwiw 200* is very toasty, but that usually comes with 1800-2000 deg EGT's.

Remember, as a rule of thumb on a turbocharged Diesel engine, for every one degree you cool the intake air temp your will drop the egt by 3 degrees.

That is why the 6.7 after cooler system is not the best suited for an all out performance situation like dan's was being used in.

Most people do not need or will ever have to care. But most times simplicity always wins.

When did Charles change his username?

 

[Crack85]

When did Charles change his username?

LOL!!!!!!!

 

[MorganY]

Sorry but I am going to have to offer a rebuttal.

The fact that water transfers heat better than air is nothing new.

The air to water to air system uses air to cool air, with water as a medium between a the two. Ford went to this system to be able to regulate intake air temps better. Obviously there is no way at all to regulate a standard air to air intake temp.

Most people do not need or will ever have to care. But most times simplicity always wins.

We're going to have to kindly agree to disagree. I understand your explanation of the differences. Air to Air to Air still doesn't do it for me. I cannot possibly type it all.

 

[swinky]

When did Charles change his username?

Lol that guys a ***king trip.

Sent from my HTC One using Tapatalk

 

[Morgan@Midwest Diesel & Auto]

We're going to have to kindly agree to disagree. I understand your explanation of the differences. Air to Air to Air still doesn't do it for me. I cannot possibly type it all.

Fair enough,

But for clarification, what we are comparing is, air to air vs. air to water to air.


Just for a very crude example.

Let's say air temperature absorption can achieve temps within 120% (80% efficient) of its own temp

And water temperature absorption is 105% (95% efficient) of its own temp.

Air to air at 90* ambient has the ability to cool to 108* by that percentage.

Water to air is more efficient, correct, obviously is can cool to a lower percentage.

But our first step is that the air @ 90* must cool the water to is best same ability, so now the water is 108*, then the water now has the ability to absorb the heat of the charge air to 105% of its own temp of 108* which is 113.4*.

Now keep in mind there are way more factors involved in real life. This test would have to be done with so many factors equaled out that it would be very hard to duplicate. Most of the outside factors would hurt the three stage "air to water to air" such as heat soak of the extra components, parasitic drag of the coolant circulation pump and various others.


Every time you go through a cooling transfer you lose efficiency. That is a fact that is irrefutable. When you are still using the same ultimate cooling source (the outside ambient air) the more steps you put it through the less effective is becomes. There is absolutely no way around that.

Two stage "air to air" > Three stage "air to water to air"

"Ice water to air" > both of those two

 

[Morgan@Midwest Diesel & Auto]

When did Charles change his username?

*** off!!






Lol

 

[drunk on diesel]

water is an excellent cooling medium, and it's great for all-out performance when you can load the reservoir with ice. It's also effective in a strictly emissions controlled application where you want to be able to tightly control IAT to the engine and need some amount of intercooling.

but for a daily driven "hot rod" diesel application that you still want to use as a truck, air to air makes more sense IMO

 

[Morgan@Midwest Diesel & Auto]

We're going to have to kindly agree to disagree. I understand your explanation of the differences. Air to Air to Air still doesn't do it for me. I cannot possibly type it all.

Anyway, I'm done. Not trying to come off as a dick.

 

[drunk on diesel]

air/water is also good on a vehicle that will see infrequent bursts at WOT... you can cool the water down over time with an air heat exchanger, and then under heavy load, you take advantage of the "battery" of heat transfer you've built up.

but in a diesel that will operate at high load continuously? air/air will yield best performance

 

[ChattyCathy]

water is an excellent cooling medium, and it's great for all-out performance when you can load the reservoir with ice. It's also effective in a strictly emissions controlled application where you want to be able to tightly control IAT to the engine and need some amount of intercooling.

but for a daily driven "hot rod" diesel application that you still want to use as a truck, air to air makes more sense IMO

If you need a damn water to air Intercooler in anything short of high competition you should drive it 200 miles and set it on fire.

 

[Morgan@Midwest Diesel & Auto]

water is an excellent cooling medium, and it's great for all-out performance when you can load the reservoir with ice. It's also effective in a strictly emissions controlled application where you want to be able to tightly control IAT to the engine and need some amount of intercooling.

but for a daily driven "hot rod" diesel application that you still want to use as a truck, air to air makes more sense IMO

Regulating IAT is the only reason ford did it. Other than that it's pointless
IMO.

Because in every sense it is not actually "water to air".

I guess what most people are missing is that we are not talking about "air to water" that would imply that there is no other cooling force cooling the water. Or a two stage setup which it is not.

In reality we are talking about air, cooling water, cooling air. All in a less efficient total outcome.

 

[Morgan@Midwest Diesel & Auto]

air/air will yield best performance

Fixed, lol

 

[drunk on diesel]

then there's that

 

[UpstateDieselGuy]

Would it also have been selected as a cold weather emission supplement? The warm coolant can also warm the charge air during extreme cold weather and help support cleaner combustion and lead to cleaner exhaust having to be treated. Just a thought.

Chris

 

[drunk on diesel]

it was definitely an emissions decision. you can keep IAT in a very narrow window so that you don't have to have a zillion different operating condition maps in the tuning

 

[CATDiezel]

You guys have got to definitely keep in mind how a LOW NOX engine functions. The more efficient you burn past a certain point the nox increases. To decrease NOX (NO chemically bonded with NO2) you have to have a less complete burn. But don't get that Cornfused with a smokey laggy truck. We are dealing with particulates in parts per million.

Keeping the inlet air as close to consistent as possible with jacket water is solely for the purpose of keeping emissions as Consistent as possible.

Clear as mud.!

 

[CATDiezel]

We're going to have to kindly agree to disagree. I understand your explanation of the differences. Air to Air to Air still doesn't do it for me. I cannot possibly type it all.

Call Caterpillar Inc. And ask them why they got rid of air to water after coolers on non emissions engines....

I will have to agree with Sledpull on this.

BUT. I really do understand your viewpoint to.... not a bash at all...

 

[MorganY]

Anyway, I'm done. Not trying to come off as a dick.

None taken. I have learned something: I didn't put two and two together for emissions control. Makes sense. Still don't see eye to eye for performance applications.

Sorry for mucking this up D.

 

[Fast-6.0]

I think what MorganY may have been trying to express is that with the water being a better fluid for heat transfer, that for same size cubic volume the water to air is more effective, even in an air-water-air design, than an equal volume air-air intercooler. The Ford engineers were able to package in a tight system that takes up substantially less surface area than prior trucks, and giving way to a better cooling system. Trade-offs are always present in vehicle design.