Quote:
Originally Posted by Gramp34
I think you'll find other than the manifolds and fuel pump calibration, they're the same engine.
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No I don't think so. Most charge-air engines have different fuelling profiles, cam timing, pump timing, combustion chamber shapes, and so the list goes on.
Quote:
Originally Posted by Gramp34
You can turbocharge (or supercharge) a diesel without adding an aftercooler. By cooling the compressed intake air, you can stuff more oxygen into the cylinders, which can then burn more fuel and produce more power than with just the turbo.
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An intercooler (between the turbo and the inlet manifold) is what you're talking about. Aftercoolers are actually quite rare.
Quote:
Originally Posted by Gramp34
Supercharging requires power off the crankshaft to compress the intake air.
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Correct
Quote:
Originally Posted by Gramp34
Turbocharging works off the heat in the exhaust, so it compresses the intake air for 'free'.
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Wrong. The air being blown out of the exhaust spins one end of a turbine, the other end of the turbine compresses the air into the manifold. It has nothing to do with heat. Heat is the biggest enemy of engine efficiency which is why there are things like pre-coolers, intercoolers and aftercoolers.
Quote:
Originally Posted by Gramp34
The benefit of supercharging is to put more air into the engine, which allows you to use more fuel and produce more power. It doesn't improve the efficiency of the engine.
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What?!?!? Double the horsepower from the same cubic capacity?? No improvement in efficiency??
Quote:
Originally Posted by Gramp34
In fact, the power to drive the prop will still be the same, but the engine will probably burn more fuel to go the same distance. After all, it's going to take engine power to run the supercharger, and the extra air pumped into the engine is just going to be pumped out the exhaust.
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Sorry fellows, that last piece leaves me speechless. No I can't leave it there. The energy used to turn a supercharger is a very small fraction of the power that results from the charging of the engine. To say that the result will be the same or less efficient, is nothing short of daft.
Gramp has obviously never heard of drag racing. Nufsed.