Article in yesterday WSJ about significantly increased fuel economy in gasoline engines that use direct fuel injection. I thought todays fuel-injected engines already did that.
“Put your creed in your deed.” Emerson
“When asked if you can do something, tell’em “Why certainly I can”, then get busy and find a way to do it.” T. Roosevelt
Replies
Not exactly, most of today's engines use 'port"fuel injection where the fuel is injected ahead of the intake valve in the intake manifold just before the cylinder head. A ' direct injection engine has the fuel injected directly into the combustion chamber.
Bruce
There are actually several different variations of non-direct injection. Some have a single injector in the "throttle body", while others have multiple injectors in the intake manifold, though not always one per cylinder.Direct injection is how a diesel engine works, of course. It requires high pressure (15000 PSI), whereas the others just require 100-200 PSI or so.With direct injection gas engines they can play games with injection timing (since ignition is via spark, not compression), injecting during the intake stroke for a rich mixture or injecting during the compression stroke for a lean mixture, reducing emissions and improving efficiency.http://en.wikipedia.org/wiki/Gasoline_direct_injection
The modern conservative is engaged in one of man's oldest exercises in moral philosophy; that is, the search for a superior moral justification for selfishness. -John Kenneth Galbraith
You can also start the car without a starter!
Forrest
I suppose. Just figure out what the crank position is and inject fuel into the cylinder that maybe 1/3 of the way down on the power stroke, then fire the spark plug. Kind of a built-in Coffman starter.
The modern conservative is engaged in one of man's oldest exercises in moral philosophy; that is, the search for a superior moral justification for selfishness. -John Kenneth Galbraith
Sort of - actually, they squirt and fire a cylinder that's coming up on its compression stroke, which spins the crank a ~ half turn backwards, compressing another cylinder which is then fired to kick the engine in the correct direction, and then the normal firing is initiated.
Cool!
Forrest