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Intake/exhaust port CFM flow? Porting the heads? Tech babble.

SCSG-G4

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The stock air cleaner element is rated for 410 cfm, so if the turbo pulls more, somethings gotta give, and it will be going through the engine when it does.

Without a turbo, the piston is sucking the air into the cylinder on the down stroke, with a turbo it's still doing the same, but the pressure on the intake side gets more air into the cylinder in the same amount of time. Here's a little experiment to help visualize how that works. Put a balloon over the end of an air hose and set the pressure regulator to 2 psi, then inflate the balloon and time it. Repeat at 5 psi, 10 psi, and 25 psi. See how much faster air moves as the pressure goes up? That's why the Germans call a turbo a Kompressor!
 

gimpyrobb

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I think you have a good idea. Getting more power out of a multifuel. If you found out exacty how much air the stock turbos force into the engine, couldn't you just install a larger turbo that produces the air flow you want without other modifications to the heads? I guess I'm still trying to understand this. Lol.
You will eventually blow out your head gaskets from pressure. Better flowing heads will reduce your EGTs an improve efficiency.
 

merlot566jka

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Is the air moving faster or is there just more air moving at the same speed? Remember psi is pounds per square inch. The illusion of filling a balloon doesn't work because you are putting more dense air in each time you increase pressure, meaning you're moving more air, but your not moving it any faster.

Take a look at this explanation...
answers.yahoo.com/question/index?qid=20080717034851AAsFKFW

Bottom line,
Velocity increases, pressure decreases.
Velocity decreases, pressure increases
Volume of air (in the intake, port, plenum) increases, velocity decreases, pressure increases
Volume of air decreases, velocity increases, pressure decreases.

In a turbo, the vanes compress the air as it turns, further and further each time. The volume of air stays the same but it's forced into smaller area each step of the way. As the volume of the container gets smaller, the pressure increases because its the same amount of air forced into a smaller area.

Sorry about errors. At work and driving.
 

doghead

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I think you'd be better off just cooling the intake air.
 

treva2

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Cooling the intake charge is the easiest way to lower egts. However, I've been told the MF intake manifold has water/coolant jackets cast into it. Which makes it impossible to lower the intake charge any lower than the temp. of the water, approx. 180 degrees. I'm planning on building an intake with the water jackets detached from the intake to eliminate the heat transfer, and running a inter cooler. A little bit of work but I love the design and fabricating. Some refer to this as enjoying the journey more than the destination.
 

merlot566jka

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See my thread on water to air intercooling. I will put up pics of the inside of the intake. It is not able to heat the airline like everyone thinks. There is not a heat exchanger in it. It's a water jacket.
 

rmgill

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Hmm, what about arranging the radiator for the intercooler parallel to the right side vented fender area? Add an electric blower there for the airflow?
 

merlot566jka

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I thought the same. But looked at the area and didn't think there would be enough airflow.
I looked at what would happen if it were mounted in front of the radiator. It looks like that will work as long as the intercooler radiator is thin enough.
Aside from that, I looked at the hummer style "in hood" radiator. Also thought about mounting it at an angle beneath the front of the engine radiator.
Putting a fan to draw through or blow through is going to be essential. When towing a load up a steep grade, I was lucky to get 40mph and my EGT was hovering around 1200* pre-turbo. 40mph isn't nearly enough air to cool if you ask me.
 

w3azel

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Someone installed an Isuzu intercooler on their deuce with good results and instructions. I have the thread saved somewhere but the wife is taking a test on my laptop so ill find it later. I still interested in the porting. I've been trying to read up on Hercules D4800 and D5000 engines. From the few threads I found on them these heads flow very well. Some say better then 8.3 Cummins.
 

rmgill

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Off the cuff, I'd think an aux fan blowing air through the right side fender area would work reasonably well and not parasitize cool air from the engine radiator.

What about a scoop on the front right air intake plus from under the front right headlight ducted into the unit with an aux fan?
 

merlot566jka

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Someone installed an Isuzu intercooler on their deuce with good results and instructions. I have the thread saved somewhere but the wife is taking a test on my laptop so ill find it later. I still interested in the porting. I've been trying to read up on Hercules D4800 and D5000 engines. From the few threads I found on them these heads flow very well. Some say better then 8.3 Cummins.
Interesting. Is tat the civy version of the multifuel? Any flow numbers on them?
 

w3azel

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http://www.steelsoldiers.com/showthread.php?43109-M52a2-aia-to-air-intercooler Found it, sorry its a 5 ton not deuce. As far as the heads from what I understand the block and heads are identical between the civi and military engines. The Civi does have different parts added and a few more holes to bolt on a tractor water pump. I guess its different then a normal one. The civi version can only run on diesel and has a lower compression but a version was made that made 228 hp factory. The Hercules is a popular engine for tractor pullers. I'm trying to find the gap between popular engine that people compete with and put as much power out of as possible and these delicate flowers we have in our trucks. EDIT: Found more on the engines, still can't get flow rates and actually when you start to get up in power the heads do hurt because they are not cross flowing. If I had the money Id like to see about switching to the tractor internals to lower the compression down to 18:1 and then dial up the power. I wish hemichallenger would give us some info on his Bolt on power kit. From the list of parts I can only imagine porting and polishing is somewhere in his process. I understand wanting to make a few $ but for that much money I can get three engines and do whatever to them.
 
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HanksDeuce

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[sarcasm]
I can't believe the typical responses haven't hit this thread yet:
1) Will you tell your insurance company that you modified the heads for more airflow?

2) Why does your deuce need to be any faster?

3) How will you stop your deuce with all of this extra power?

Think about public safety!
[/sarcasm]

LOL! Keep us hot rod deuce owners in the loop on anything you complete for this effort. I'm looking for mods to decrease my 0-60 time (Cummins 6BT swap, drop 3000 lbs, etc).
 
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merlot566jka

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Lol. I know, it's shocking the naysayers haven't started in on me.

But this is all about efficiency. The deuce is plenty fast for me. I don't want a higher top speed. And sure, ill tell my insurance company... They have my truck listed as a "Tank" anyway.
 

oddshot

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Did anybody ever bench flow their heads before and after porting/polishing? If so what were the results?
THAT is a great question. I would love to see numbers off a flow bench.

I've never done any performance work on a diesel engine, but I have done enough gasoline engines to know that not every engine responds well to porting and polishing. Some heads have been designed and cast to max efficiency and there are just not any gains to be had. On the other hand, some engines are really choked down and respond unbelievably well.

If I had to make a guess, I would think that these heads were designed for cost, simplicity and reliability. Consideration of power would probably have been 4th and economy a very distant 5th. There just might be some gains to be had in doing these heads.

A 10 or 15% gain won't mean anything at all who only uses his Deuce 3 or 4 times a year. Many hobbyists in this community won't understand why anybody would want to do this.

My truck is my daily driver, and I have been involved improving production vehicles (aka "hot-rodding") all my life so this conversation means a lot to me.
 

oddshot

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Lol. I know, it's shocking the naysayers haven't started in on me.
:ditto:

But this is all about efficiency. The deuce is plenty fast for me. I don't want a higher top speed. And sure, ill tell my insurance company... They have my truck listed as a "Tank" anyway.

Yep. It ain't about speed or power ... and it really could mean more than just MPG's. Just making certain that each cylinder is getting the exact same volume of air as its brothers could extend the life expectancy of this engine quite a bit.
 

Docluvstrucks

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:ditto:




Yep. It ain't about speed or power ... and it really could mean more than just MPG's. Just making certain that each cylinder is getting the exact same volume of air as its brothers could extend the life expectancy of this engine quite a bit.

Agreed. I have little interest in hot rodding. Efficiency and longevity however is what I am interested in. I have two diesels and a multifuel. All the work and add ons are driven by the aforementioned. Lets call it an engines Feng Shui or homeostasis. Everything in balance

Porting and polishing is one thing but let's throw this out there, EXTRUDEHONE. Pricey but is it anybetter than porting and polishing? Seems like extrudehone would take the human factor out for even more uniformity.
 
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