Why?

[713Diesel]

Let me start of with I absolutely love my 6.4. It is by far the best truck I have ever had and I have had all of the powerstrokes starting with the IDI. With that said I continually find myself wondering why the folks that engineered and designed the 6.4 did some of the things they did. I believe I have my facts straight but if I do not please do not hesitate to correct me. My questions are as follows:

#1. Why the designed the exhaust manifolds the way they did. New developments, primarily Steeds manifolds have proven that the stock one's do not flow very well. Hell going back a generation to the 6.0's is a upgrade. Anyone that looks down the stock ones will automatically think "well that's not right".
#2. Why wouldn't they spend more time making a better flowing head. This is where I want someone to either confirm or correct me. If I recall correctly a stock 6.4 head does not flow nearly as well as a cummins. You can port and polish a 6.4 head to flow just a little bit better than a STOCK Cummins. Then of course you can PP a Cumins which would blow the 6.4 PP out of the water. I would have to assume with all the R&D that go into these motors head flow would be something that they measured. When they got these results you would think they would have said "oh, a DMAX does more than that and HOLY COW a Cummins does what?, we better rethink this one". It has been my experience in engine building, I will admit I have only built NA gas motors, but if you are going to spend a bunch of time and money on something it should be in the heads no questions asked.
#3. I know they made the head bolts bigger in a 6.4 but since it was such a disaster in the 6.0's why wouldn't you add more? Is there physically just no room? Is the block the same as the 6.0 so they kind of had to make what they had work?
#4. Why wouldn't they have used a more tried and true HPFP? From what I understand the CP3 pump that they have been using on the Dmax's just about set the standard and are far better than our K16 pump. Is it a cost issue? Is it one of those deals where the GM guys are going to say we copied you?

Like I said before, I love my truck and I wouldn't change it for the world. I truly believe that this is the best diesel truck that you can buy. What else can you get and sink 2k into it and have a 550 Hp and 1000 ftlb all the while not having to worry about blowing up your transmission in the first 1000 miles?

If these four issues were taken care of from the factory there would be absolutely no question about what the best diesel truck out there is. #1 and #2 are absolute no brainers. ANYONE that knows ANYTHING about ANY engine that is out there knows that you need to flow air to make power. Heads are the most important piece in flow. You can only make the stock design so much better and IMO International set us up with a pretty good uphill climb. I know turbo's help negate the bad flow but at the end of the day flow is still flow. The exhaust manifolds are just crazy........ I don't know how they could design and walk away from that mangled piece of iron. #3 just blow my mind. I really hope there is a good excuse as to why we didn't get more bolts especially if they had to redesign the block for the 6.4's. #4 I can understand as our pump probably is completely fine for a stock application but you can always wonder.

It is frustrating to know that they go so much right with this motor but they just made some mistakes (#1, #2 and #3) that are just items that you would think these guys would have seen and said "hold up..... let's think about this a little more". I try not to dwell on the negatives in life but I cant help but think at the end of the day we paid an additional 8k for this motor. Figure in financing over 5 years it comes pretty close to 10k which is over a years worth of payments for most of us.

Just wanted to see if anyone had any thoughts or answers. Sorry for being long winded, this is just something that has been brewing in my head for quite sometime.

 

[Petro]

I also was wondering the same things. But isnt the Siemens pump one of the reasons the 6.4 is such an animal to begin with? doesnt the K16 pump outflow the CP3 by some 30%?

 

[713Diesel]

I also was wondering the same things. But isnt the Siemens pump one of the reasons the 6.4 is such an animal to begin with? doesnt the K16 pump outflow the CP3 by some 30%?

Quite possibly. Like I said half of my email was to check my logic. Maybe the deal is that the CP3 pump is easier to modify? I believe I heard you can modify a CP3 pump to flow way more than stock.

 

[White_monster]

#1 manifolds were designed to make the engine quieter and smoother feeling in the cab. They get the power needed from factory just fine so there's no need for the extra flow possibilities.

#2 the heads flow perfectly fine for the stock power. Sure the others flow more but why spend money making the heads flow more than is needed, you really think Ford or International care that we want to modify these trucks, I think not.

#3 extra head bolts add cost. Make them bigger and use less means less cost and more profit. Also the block is ultra close to the 6.0L so it most likely saved a pile on retooling. Again all comes down to profit.

#4 Not sure but maybe it was cost or international is connected with Siemons some how.

 

[uga33]

While it does flow much more fuel than a CP3, they are not as reliable.

 

[713Diesel]

#1 manifolds were designed to make the engine quieter and smoother feeling in the cab. They get the power needed from factory just fine so there's no need for the extra flow possibilities.

#2 the heads flow perfectly fine for the stock power. Sure the others flow more but why spend money making the heads flow more than is needed, you really think Ford or International care that we want to modify these trucks, I think not.

#3 extra head bolts add cost. Make them bigger and use less means less cost and more profit. Also the block is ultra close to the 6.0L so it most likely saved a pile on retooling. Again all comes down to profit.

#4 Not sure but maybe it was cost or international is connected with Siemons some how.

#1 That makes sense. I find it funny that there for the longest time guys were saying they didn't want a diesel because of how loud they were. Now guys complain that a diesel motor doesn't sound like a diesel motor any more lol.

#2 I disagree. The heads to flow perfectly fine for 325 hp. But I don't you think Ford/International would have loved to say that their motor makes 350 or 375 hp? I am just saying that whenever you spend the time/money on R&D wouldn't you think that you would try to achieve better than what you already have or what is already out there by the competition? My point is that head flow is a big deal and based on the flow #'s that I have seen for a stock 6.4 head leads me to believe that the engineers didn't think that head flow was a big deal. I tried to find the #'s that someone posted somewhere about the CFM that each of the stock big 3 produce but I cant find it to save my life.

#3 I understand on the retooling cost. This one I imagine comes down to International seeing the writing on the wall with its relationship with Ford. I imagine it was well known by the time that the 6.4 was designed that both of them were going to separate their ways. I disagree with your statement on the extra cost on the head bolts. In the grand scheme of things this cost would be minimal, especially considering all the heart ache/legal costs they are experiencing with head studs from the 6.0. Also there is an economy of scale when it comes to this sort of thing. Its not like those guys buy 50 or 200 bolts at a time. They buy thousands at a time. So just for ease of #'s lets say that the stock head had 10 head bolts that cost them 100 bucks. If they went with 20% more bolts up to 12 head bolts I do not believe the cost for these would go up 20% to 120 bucks. The more you buy the cheaper it gets and when you have 10 different contractors bidding against each other for the contract to supply bolts to international I think the cost will be a very minimal increase. But that is just my opinion.

#4 Probably so. I really have no idea. Now that I think about it more the K16 pump is quite more expensive than the CP3 pump from what I understand so I hope it is better.

 

[6.0dirtworker]

Here's a ballpark from what I remember. Pretty sure it was empire's thread.

Powerstroke
Stock: 120cfm
Ported: 160cfm

Duramax
Stock: 160cfm
Ported: 240cfm

Cummins
Stock: 180cfm
Ported: 220cfm

 

[01PSD]

Well that's depressing. LOL

 

[LovinPSDs]

wouldn't better heads and mani's help the efficiency and in turn help with the emissions?

I'd like to see a dang motor stick around for more than a few years! It really is a shame that the 6.4 had such a short production run..

 

[713Diesel]

Here's a ballpark from what I remember. Pretty sure it was empire's thread.

Powerstroke
Stock: 120cfm
Ported: 160cfm

Duramax
Stock: 160cfm
Ported: 240cfm

Cummins
Stock: 180cfm
Ported: 220cfm

That is EXACTLY what I remember reading....... wow it was worse than I remember.

 

[Charles]

A head that flows a tremendous amount higher with the same basic port shapes, layout and number would almost certainly have to lose velocity, swirl and efficiency.

So since the engine was engineered to produce _____ horsepower, it should come as no surprise that the heads were engineered to also flow sufficient air for that power, and not be designed to flow enough for 6 times that... at the cost of efficiency at the flow rates the head was designed to operate at.

As for the cummins, each of those ports is responsible for supporting 32% MORE power than the ports of the duramax or the Ford because it only has 6 cylinders! This means the design flow for those ports will be 32% greater for the SAME engine power at the same engine efficiency. And if you look.... that not coincidentally, is about how much more they flow per port than their V8 brethren...

The cummins guys didn't make a head that flowed way more to make more power. They designed a head that flowed about 32% more per cylinder so that it could support the increased per cylinder requirements of the 6 cylinder configuration.

 

[713Diesel]

wouldn't better heads and mani's help the efficiency and in turn help with the emissions?

I'd like to see a dang motor stick around for more than a few years! It really is a shame that the 6.4 had such a short production run..

I would think so on the emissions. I would really like to see what kind of better MPG's we would be getting with a better flowing head (180 cfm) and more free flowing exhaust manifolds. If anyone reading this hasn't seen the results that they got from the Steed Speed exhaust manifolds, look it up. It is very impressive.

 

[White_monster]

The 6.4 is still made by international. It's called the maxxforce 7. There's a lot of differences on the top end but the bottom end is the same. The engine manufacer set a hp goal and that's how they came to the flow numbers they gave us. All they wanted to achieve was 325hp at the crank and what they gave us is just that.

 

[713Diesel]

A head that flows a tremendous amount higher with the same basic port shapes, layout and number would almost certainly have to lose velocity, swirl and efficiency.

So since the engine was engineered to produce _____ horsepower, it should come as no surprise that the heads were engineered to also flow sufficient air for that power, and not be designed to flow enough for 6 times that... at the cost of efficiency at the flow rates the head was designed to operate at.

As for the cummins, each of those ports is responsible for supporting 32% MORE power than the ports of the duramax or the Ford because it only has 6 cylinders! This means the design flow for those ports will be 32% greater for the SAME engine power at the same engine efficiency. And if you look.... that not coincidentally, is about how much more they flow per port than their V8 brethren...

The cummins guys didn't make a head that flowed way more to make more power. They designed a head that flowed about 32% more per cylinder so that it could support the increased per cylinder requirements of the 6 cylinder configuration.

Interesting and that makes sense. Since you sound like you know what you are talking about why do you think the duramax has such a higher CFM than we do? They make about the same amount power as us and they get better MPG's which would lead me to believe that they are not losing velocity, swirl and efficiency. Do we have lower CFM on the head and make it up on superior turbo's to make up for the lack of natural flow? For the record I am actually asking the question and I am not trying to sound like a smart ass.

 

[Charles]

Interesting and that makes sense. Since you sound like you know what you are talking about why do you think the duramax has such a higher CFM than we do? They make about the same amount power as us and they get better MPG's which would lead me to believe that they are not losing velocity, swirl and efficiency. Do we have lower CFM on the head and make it up on superior turbo's to make up for the lack of natural flow? For the record I am actually asking the question and I am not trying to sound like a smart ass.

The duramax is a larger displacement engine, that will account for some of the increased flow requirement, other factors are the bore to stroke ratio and piston velocity. On the duramax for instance the bore to stroke ratio may cause the piston to drop faster, requiring greater port flow rate for the same rpm and power output.

There are many possible factors.

 

[713Diesel]

Gotcha. If I remember correctly the bore is bigger than the stroke on a Dmax. So with the little bit bigger displacement on the Dmax and the bore to stroke ratio is substantial enough to call for 33% more cfm than what we have? Once again I am asking the question not trying to sound like a smart ass.

At the end of the day I have to wonder how the Dmax and cummins guys are making similar power with turbo that is not as good as ours and they get better mileage. Not trying to start an argument but I have to believe it is somehow correlated to head flow.......... but maybe that is just me being ignorant lol.

 

[Strokin6.4]

What duramax or cummins makes 550+ hp with an intake, tune, exhaust..... NONE. I know of a duramax with intake, tune, exhaust and nozzles making 530hp though. Its wierd how stock CP3 can maintain big nozzles and our pump hardly maintain 24,500 with stock nozzles. I know mine can't anyway. 21,000-22,000 if I'm lucky.

Sent from my SCH-I500 using Tapatalk 2

 

[713Diesel]

What duramax or cummins makes 550+ hp with an intake, tune, exhaust..... NONE. I know of a duramax with intake, tune, exhaust and nozzles making 530hp though. Its wierd how stock CP3 can maintain big nozzles and our pump hardly maintain 24,500 with stock nozzles. I know mine can't anyway. 21,000-22,000 if I'm lucky.

Sent from my SCH-I500 using Tapatalk 2

I agree! Like I said no other truck can do what ours can with a simple tune, intake and exhaust. It has just been my understanding, and I could be completely wrong on this, that the CP3 pump is a better all around pump. Some have said that the K16 is a better pump in stock form..... i honestly don't know..... I am pretty sure you can modify a stock CP3 pump to flow quite a bit more than stock and I have not heard anything like that about the K16 pump. But as I have said all along this is all that I have seen in the research that I have done........ I could be completely wrong and I just want to hear what others have to say.

 

[Corb@CorbinShipping]

I agree! Like I said no other truck can do what ours can with a simple tune, intake and exhaust. It has just been my understanding, and I could be completely wrong on this, that the CP3 pump is a better all around pump. Some have said that the K16 is a better pump in stock form..... i honestly don't know..... I am pretty sure you can modify a stock CP3 pump to flow quite a bit more than stock and I have not heard anything like that about the K16 pump. But as I have said all along this is all that I have seen in the research that I have done........ I could be completely wrong and I just want to hear what others have to say.

Just from what I have seen around, the CP3 is more popular, as far as #s produced, and more companies are digging into them, and modding the crap out of them, and making big flow/hp #s. The K16 seems to have Industrial Injection..... bleh.... and adding a second pump. Until Elite finally comes out with their upgrade..... (JD, that would be a nudge.... LOL) I am all about options. And RCD is using a CP3 in their double pump kit.... OPTIONS......

But I am satisfied that in stock form, the K16 is pretty bad ass. Concidering the HP #s we can put down with a stock fuel setup. High Powers on stock fuel made 700 hp, tow powers on stock fuel made 640 or so, and my old Xs made 680..... stock fuel in our rigs are pushing 700 hp.... cheby and dodge havent got that far yet... and our injectors are pretty bad ass too.... easy and cheap to get more out of them.

Better flowing heads would def not be unappreciated though.....

 

[Nos_GTSR]

The II pump may have been hit or miss (mostly miss) but if you got a good one it was good for a 1000hp. I don't know if a single cp3 could. I've always seen Twin cp3s on high HP duramaxs so I don't know.