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Author Topic: Charge air cooler impact?  (Read 977 times)
shelled
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« Reply #15 on: June 19, 2014, 05:08:18 PM »

one overlooked impact of the charge air cooler is that it will reduce NOx emissions which are created when the combustion flame front exceeds a certain temperature -- I'd have to look up the exact temp.  A cooler air charge helps control the flame front temp.

edward
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Rampside/UltraVan/Excalibur/4104/4107/etc -- Dallas Tx
TomC
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« Reply #16 on: June 20, 2014, 08:37:22 AM »

Virtually all Diesels in vehicles are both turbocharged and have air to air intercoolers, or aftercoolers. Yes they reduce the air intake temperature, but a naturally aspirated engine will still have a cooler air charge coming in. The main way now that engine manufacturers are combating the NOx is to have up to 5 injection events per power cycle. The one big hit that mechanical injection does creates a big spike in combustion temperature causing higher NOx. The multiple smaller hits keeps the combustion temp down and NOx down. The nice sideline of this is that it also quiets the engine down with the old fashioned Diesel knock. Good Luck, TomC
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Tom & Donna Christman. '77 AMGeneral 10240B; 8V-71TATAIC V730.
shelled
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« Reply #17 on: June 21, 2014, 07:05:02 AM »

Virtually all Diesels in vehicles are both turbocharged and have air to air intercoolers, or aftercoolers. Yes they reduce the air intake temperature, but a naturally aspirated engine will still have a cooler air charge coming in. The main way now that engine manufacturers are combating the NOx is to have up to 5 injection events per power cycle. The one big hit that mechanical injection does creates a big spike in combustion temperature causing higher NOx. The multiple smaller hits keeps the combustion temp down and NOx down. The nice sideline of this is that it also quiets the engine down with the old fashioned Diesel knock. Good Luck, TomC

things I wish I understood better -

Cooler air charge in a naturally aspirated diesels does not apply to DD 2-stroke engines because of the Rootes "blower."  I keep wondering about replacing the Rootes blower with a twin-screw (whipple) supercharger which supposedly uses less power and heats the air less.  Does anybody have info about this ?

as best I can tell, the intricate passages in the DD's unit injectors either do or could accomplish the same thing as the multiple event injectors on newer engines but I have not seen this issue addressed.  Any pointers ?

My interest in the above is fuelled by the need to decide exactly what I'm doing building a new engine for the 4104 I rescued.

edward
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Rampside/UltraVan/Excalibur/4104/4107/etc -- Dallas Tx
TomC
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« Reply #18 on: June 21, 2014, 08:20:52 AM »

Whipple superchargers have been replaced on Detroits. I saw one done on the 6V-53 on Youtube.

But-remember the roots blower is made for the engine with the governor drive on one end and the fuel pump drive on the other. I would think converting to a Whipple would be much harder then appears. The inefficiencies of a 2 stroke is going to always keep you from getting the same mileage as a 4 stroke. Converting over to a 6 cylinder 4 stroke would be much more effective-and would boost your power, torque and worth of the bus. Good Luck, TomC
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Tom & Donna Christman. '77 AMGeneral 10240B; 8V-71TATAIC V730.
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« Reply #19 on: June 21, 2014, 09:22:21 AM »

Whipple superchargers have been replaced on Detroits. I saw one done on the 6V-53 on Youtube.

But-remember the roots blower is made for the engine with the governor drive on one end and the fuel pump drive on the other. I would think converting to a Whipple would be much harder then appears. ... Good Luck, TomC

Currently available Whipple superchargers are made for (relatively) small, higher revving 4-stroke applications and the 6V53 is about as large a 2-stroke as they will readily fit because, in addition to the governor and fuel pump drive issues, there is a major, major issue with providing the needed RPM to drive the Whipple supercharger.  And then there is the issue that air flow in a Whipple supercharger goes from end to end even when the inlet and outlet may be on the sides.

So, as you say, it's "much harder than it looks."

edward
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Rampside/UltraVan/Excalibur/4104/4107/etc -- Dallas Tx
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