Stock 6.0L diesel cylinder head flow numbers.

Spectre32

There are special machines that flow test heads. They work off of a head with valve train installed. The machine puts a vacuum under the head (combustion side) and depresses the valves down. It takes measurements at each of the above reference points.

As far as a Duramax or Cummins head. I don't know exactly. A cummins head is very hard to flow since it uses siamese ports. Most people, who are flowing them, are flowing them incorrectly. As far as I know, there are only one type of bench made that can properly flow a siamese port and they just came out with it. (Someone correct me if I'm wrong here).

Duramax heads, someone should know.
 
The head was flow tested at Wilson Manifolds on a superflow flow bench. I asked if they had ever flow'd any other diesel cylinder head and I was told they had flowed a CR head and at max flow it flowed 169 cfm at the same lift of the ford.

They have produced their own intake horn for the CR guys and one of the employees uses his truck for the R&D. Luckily they are 15 minutes away from me.
 
Close to a cummins eh? Then why cant we turbocharge like one! I know I know..inline6 vs V-8 = no comnparsion.. shorter exhaust gas travel to the turbo... etc etc.
 
You can if you move a few things around. And redo the camshaft. Need a clean charge in the cylinder.
 
Spectre32 said:
Close to a cummins eh? Then why cant we turbocharge like one! I know I know..inline6 vs V-8 = no comnparsion.. shorter exhaust gas travel to the turbo... etc etc.
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Actually on that note, would be interesting to know the Cummins' exhaust flow. The intake is close to the same, what about the exhaust? I would assume it is much higher than our 12X.
 
hpprose said:
Actually on that note, would be interesting to know the Cummins' exhaust flow. The intake is close to the same, what about the exhaust? I would assume it is much higher than our 12X.
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Why would it be higher?
 
Their EGR system doesn't exist, they are able to spool the same turbo much more efficiently (cannot believe it is simply because of the dual volute design) and the power issue.

I'm assuming they are able to clear the exhaust out of the cylinder and fill it with clean new air much easier than we are.
 
hpprose said:
Their EGR system doesn't exist, they are able to spool the same turbo much more efficiently (cannot believe it is simply because of the dual volute design) and the power issue.

I'm assuming they are able to clear the exhaust out of the cylinder and fill it with clean new air much easier than we are.
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So EGR issues aside.. considering we can delete that pile of F... that whole.. clearing exhaut issues.. would that be due to the Inline advantage.. or is that something with the head(s)?
 
Look at how much overlap there is. And then ammount of delay of the intake valve after top dead center. If there is still pressure in the cylinder when the intake valve begins to open it will push back against the intake charge. So if we delay the intake valve from opening until the piston has dropped far enough for the pressure to dissapate we would be alot better off.
 
As Doug said, the EGR issue is within the design of the system. Not just the cooler and valve that can be removed easily. The cam is designed to have high back pressure to help the exhaust overcome the boost pressure in the intake and flow when the EGR valve opens. So, by the factory design, backpressure should always be higher than boost.

Now a good aftermarket turbo, with a wastegate, etc can overcome that disadvantage and equalize the pressures out, but that's after the cylinder, not in the cylinder. The cylinder can only be cleared out by the cam timing, lift, overlap etc (which I don't know a whole lot about).
 
So can a cam be built to do such a thing.. or is this the whole reason where having this discussion? If thats the case then why are the duramaxes not affected by this.. or so as much as we are? They have EGR's just like us.
 
Since the Heui injector has a tough time firing a second time for say a post commbustion injection it needs to find a way to mechanically reduce hydrocarbon emmissions. Where as the Dmax guys can use EGR to reduce oxides of nitrogen and a post combustion fuel injection to reduce hydrocarbon emissions.
 
so i take it your trying to develop a camshaft to correct the over lap? i gotta admit the more i find out about the 6.0 the more i am dissapointed with it, but i guess the cummins & dmax have their down falls too? ...or do they :-\
i wonder if the cam overlap issue is why these engines respond so well to nitrous since they dont get a clean charge with just a turbo powering it.
 
I picked up a signifigant increase with good bowl work. But these seats make for some tough porting.
 
Is that the cylinder total # or per port #'s? Also was this the tested number with an attached cylinder to simulate valve shrouding? Thats also very important to determine true flow characteristics.

Also keep in mind if your just going for flow you need to consider the critical characteristics of swirl needed in a direct injected diesel..especially a multi-valve. this is where real development will involve smoke testing within a cylinder using a piston at varying depths corresponding with valve height. the guy who gets this right will have the best heads on the market. bottom line is true development will require cylinder simulation..not just a "simple" flow bench.
 
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It was sitting on a head gasket and an aluminum cylinder to simulate the cylinder.
 
Why are the heads to difficult to port? Does it even matter, can the intake plentum supply amble enough air to even go forth and port the heads?
 
My Stage one manifold removes all of the internal restriction and adds some volume to the plenum. I want to port the heads and run them on a truck to compare them.
 
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