When someone uses the term naturally aspirated in the 3208n, for example, is the aspiration referring to how the motor is cooled?
Yes, ditto.Thanks for the information and clear explanations.
ken
Aftercoolers and intercoolers only cool the intake air charge, not exhaust. Actually, keeping the exhaust hot into the turbo creates more boost. Older DDs with "dry" turbos made more hp than the later model same engine with the "wet snail" exhaust housing.. Some DDs are both after and inter cooled, with high flow bypass on the blower. The supercharger (blower) actually becomes a restriction at high turbo boost.
On DD two strokes, there is a difference. A TI has the charge air cooler between turbo and blower, a TA has the cooler between blower and engine.
TI: Turbo to cooler to blower to engine
TA: Turbo to blower to cooler to engine
And back to the Detroit 2 cycles. They have both a supercharger for startup and low rpms, but modern ones have a turbocharger before the supercharger.
Turbos and all the goodies added to a NA are to increase the power.
This requires an increase in fuel burn.
An engine is considered to be able to burn a certain number of gal of fuel before its worn enough for a rebuild.
Burn fuel at 3 times the basic rate and the engine life in hours will be at least 3x shorter
If you need plenty of power to operate a sport fish the goodies will give it to you.
If you operate a displacement boat there is little need for the cost and complexity of turbos or anything else.
Just install a DD that operates at 60%+ of rated HP or more and enjoy the insane number of hours these NA engines can operate.
Happily the 1936 design allows some selection of rated HP by changing injectors or timing,if the vessel service changes.
Turbos do not increase fuel burn. If you have a choice between a TA engine and and a NA engine to make say 300hp, the TA will burn less fuel doing the same job.
OK Sky, you're right on this one. A turbo engine will not burn more fuel (at idle) but once you start extracting that extra horse power offered by the turbo, you pay for it in fuel costs and accelerated engine wear.
The reason why more engines are equipped with turbos are mainly due to environmental regulations requiring a more complete burn of the fuel. The secondary reason is you get more horsepower out of the same sized engine with nearly the same weight.
As my father used to say, if a candle burns twice as bright, it lasts half as long.