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  • turbo charged

  • Discussion of General Electric locomotive technology. Current official information can be found here: www.getransportation.com.
Discussion of General Electric locomotive technology. Current official information can be found here: www.getransportation.com.

Moderators: MEC407, AMTK84

 #50327  by DutchRailnut
 
No for a 4 stroke diesel a Turbo Charger is needed. a Two stroke can get away with a Roots blower

 #50332  by St-Jean Diamond
 
But a 4 stroke can breathe by itself without any aid.. Makes me wonder... Btw Hi Terry, the Alco sounds on your site are pretty cool :P
 #50438  by WebInfo
 
Terry, I have asked you this before: Why do you want to "de-turbo" every diesel on the planet???

Sure, you can deturbo any 4 stroke, you can also deturbo an EMD as long as you use a roots blower for exhaust scavenging.

Why do you want to do that? The extra cost of maintenance for a turbo is minimal when you calculate the increased power output AND increased thermal efficieny for a diesel. Diesels and turbochargers are a match made in heaven.

Just look at the specific fuel consumption for a non turbo vs. a turbocharged diesel for a given HP output. I want all my diesels turbocharged!!!!

 #50490  by Justin B
 
Because it is a 4 stroke engine, the FDL can theoretically operate without artificial aspiration, unlike a 2 stroke that needs air to be blown in for cylinder scavenging. However, the FDL was never designed to operate without a turbocharger, so even though it will probably fire with out one, its thermal efficiency will be absolute crap. No railroad in their right mind would ever de-turbo a GE locomotive.

 #50874  by Typewriters
 
This may be stating the obvious. If you have a given type of engine available as either normally aspirated or turbocharged, you do not have the same valve timing or injection timing on the two. You may note that Baldwin offered the 600 series in six or eight cylinders and, early, in normally aspirated form in six and eight cylinders and turbocharged in eight. When it was found that economies in manufacturing could be realized by replacing the eight cylinder, normally aspirated engine with a six cylinder turbocharged engine, this was done.

But also note that the valve events, as regards degrees of crank rotation at which intake and exhaust valves opened and closed, and the timing of fuel injection differed between normally aspirated and turbocharged engines. Compression ratio was also different between the two varieties. This means that if one were to consider deturbocharging any given four stroke diesel, one would also have to consider the other necessary modifications as mentioned here, and the availability of parts to do so.

-Will Davis

 #54038  by trainiac
 
St-Jean Diamond wrote:

But a 4 stroke can breathe by itself without any aid.. Makes me wonder... Btw Hi Terry, the Alco sounds on your site are pretty cool
Thanks! That's actually my website. I miss the ALCOs, mostly for their sound.
 #56292  by FDL4ever
 
WebInfo wrote:Terry, I have asked you this before: Why do you want to "de-turbo" every diesel on the planet???

Sure, you can deturbo any 4 stroke, you can also deturbo an EMD as long as you use a roots blower for exhaust scavenging.

Why do you want to do that? The extra cost of maintenance for a turbo is minimal when you calculate the increased power output AND increased thermal efficieny for a diesel. Diesels and turbochargers are a match made in heaven.
Amen to that! A diesel without a turbo is barely even an engine at all. Diesels are ideal for turbocharging. With a spark-ignition engine you are limited as to how much boost the turbo can produce because too much boost will cause detonation. With a diesel, the sky is the limit. Well, actually the limit is how much pressure the connecting rods and cylinder assembly can tolerate and how much fuel the injector can cram in with all that air... but many diesels don't even have waste-gates to regulate the amount of boost from the turbo. Just ask anyone who ever drove a normally-aspirated Ford or GM diesel pickup from the 80s if they prefer it to a Cummins/Dodge or a Ford Powerstroke from today.

 #56320  by mp15ac
 
I have a theory about Terry C and his desire to rebuild and deturbo everything on rails. He is a model railroader who is modeling a shortline, but wants to justify having all sorts of big locomotives. By rebuiling them and lowering the horsepower he can justify their existance on his layout.

Stuart
 #56515  by Jamshid
 
Why not! At first the electronoc card which is responsible to adjust power based on turbospeed and engine governor which has fuel limit system based on boost pressure must be ruled out. then with 12.7/1 comperassion ratio you will have the biggest mobile soot producer in the world. :-D
 #56539  by Allen Hazen
 
And if mp15ac is right about Terry C's reason for being interested, WHY NOT? I like the looks of BIG GE locomotives, but if I were building a model railroad I think I'd feel shortline/branchline railroading with lots of switching was more interesting to look at than the high-speed mainline freights the big GE's are best at! And, as any imaginative model railroader can tell you, THERE'S A PROTOTYPE FOR EVERYTHING!
In the late 1970's (I think-- may have been the very early 1980s) a coal mine in China wanted some heavy but not particularly powerful locomotives. GE rebuilt three retired E-L U33C with 1800 hp Cummins engines for them. ... As it happens, these units were to be radio controlled, and had their cabs removed (and the radiator compartment was rebuilt to something more like a U30 configuration, without the "wingspan"), but I've often fantasized about the possibility of a similar rebuild, retaining the cab (and so most of the original appearance), to make a good heavy switcher (or local freight roadswitcher) out of a retired B36-7. .... Come to think of it, CSX has a large B36-7 fleet that is approaching retirement, and their neighbor NS is feeling short enough of roadswitchers to have started rebuilding GP-50 as "GP-38-3", so it MIGHT even happen!

 #90972  by nickleinonen
 
i've run a GE dash9 [FDL16 4400hp] with the last expansion bellows removed from both banks on the engine... that engine previoulsy scattered a charger and filled the exhaust with oil... after the charger and intercoolers were changed out [and all the air box sections cleaned out] we started the engine outside with the sections removed and self loaded the engine to 3-4 notch to burn/blow out all the oil and other debirs out of the exhaust... did that for a few min, then shut down, put the bellows back, started it up, self loaded to N8 making sure boost & hp were good, then let it go back to service [boost was 43-44psi, tractive hp right around 4400 ±20hp - exhaust glowing a dull cherry :D ]

 #91094  by St-Jean Diamond
 
Being an ex-marine engineer on merchant marine ships, I've seen a fishing vessel with a B&W V-10 (1550Bhp) four stroke engine run at half speed a whole day without the turbo turning. The bearings had seized on the turbo and the ship was a day away from it's home port... The engine breathed fairly well without too much smoke... AWSOME PICTURES NICK BTW :P