tim292stro
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And there is a valve in the blower housing to allow higher intake pressure from a turbo to bypass the blower. Best way to get the most out of a 2-stroke DD was to get bigger MUI injectors (for non-DDEC), piston liners with bigger intake ports, tossing the after-cooler, putting in an extremely low pressure bypass valve in the blower (so the turbo didn't have to fight the blower), good cams, and huge fr1ggen turbo. Then you just had to worry if you had a "silver" block with more metal in the heads, which tend to heat soak and burn up...
Interestingly the older GM-EMD 576, 645, and the newer 710 2-strokes (still made!) used either roots-type blowers, or a turbo compressor - a turbo that is the reverse purpose of a turbo-shaft engine, where the turbo-compressor is driven by the engine's shaft to operate as a "blower" when the exhaust pressure was too low to add bost, and then with an overspeed clutch would be turned by the exhaust turbine at higher revs and load to function as a true turbocharger.
Blowers:
Turbo-compressor:
Always loved the sound of those BIG turbo'd 2-stokes... I think they sound "mean"
https://www.youtube.com/watch?v=hFVJ9Lhhm0I
Interestingly the older GM-EMD 576, 645, and the newer 710 2-strokes (still made!) used either roots-type blowers, or a turbo compressor - a turbo that is the reverse purpose of a turbo-shaft engine, where the turbo-compressor is driven by the engine's shaft to operate as a "blower" when the exhaust pressure was too low to add bost, and then with an overspeed clutch would be turned by the exhaust turbine at higher revs and load to function as a true turbocharger.
Blowers:
Turbo-compressor:
Always loved the sound of those BIG turbo'd 2-stokes... I think they sound "mean"
https://www.youtube.com/watch?v=hFVJ9Lhhm0I