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  • 4 weeks later...

Hey Guys.

I've been meaning to write this for a while.

Car is running fine now. No problems, no surging or anything.

A week or so after the pump went in, I reset the computer and the car is running like a dream and actually getting BETTER fuel economy.

Getting about 340 klms to a tank now.

Maybe the computer just needed to learn how the fuel was being delivered or something, or maybe the car was just due for a reset.

BASS OUT

I've often wondered myself why this occurs. I pondered what is going on and came up with the following reasoning:

The fuel pump supplies fuel under pressure to the injector.

When the injector opens, fuel flows into the manifold, and the pressure behind the injector drops.

The drop in pressure allows the pump to move more fuel in to re-establish the pressure.

Now, what happens when you install a bigger pump? A pump that can move more fuel in a given time? While the injector is open, the new pump can replace the fuel at a faster rate than the original pump could. Therefore, there is more fuel at a slightly higher pressure available to the injector. So the injector delivers more fuel at the same load.

That's my theory, anyways.

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