Thread: Muscle Car MPG?
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Old 09-21-2009, 02:52 PM   #20 (permalink)
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Originally Posted by Backtobasics View Post
EOC.... Veterans, correct me if I am wrong, but I don't see how engine off coasting can be done on a carbureted vehicle. I can turn the car off, but the engine will continue to draw fuel through the carb, into the cylinders.
That's only if you leave it in gear. If you turn the engine off with the transmission in neutral (or the clutch in), the engine will wind down and stop, just like it does when you park. If the engine isn't turning, there's no air being drawn through the carb, which means no fuel going in. (Unless you pump the throttle, in which case the accelerator pump will dump fuel down the carb throat.)

That said, I think it takes significantly more fuel to start up a carb'ed engine than an injected one. So the payback time for EOC is longer--you would need to be able to have the engine off for (wild guess) 30 seconds instead of 10 seconds to make it worthwhile.

A decent throttle body injection could work well. And if you have machine tools, you can drill the manifold for injectors and have at it. You'd definitely have to go with something like Megasquirt or another programmable EFI setup to run it, though. And that's a lot of DIY.

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