Originally posted by ButtonPuncher:
My theory is that the old pump had a hard time with quick changes in demand. With the new pump, when you stomp on the gas the pump can easily keep up with the needed pressure/volume.



What kind of mods do you have? Anything short of forced induction/nitrous, and I don't think a properly functioning stock setup will have any problems keeping up with demand. As a result I wouldn't expect a higher-capacity pump to really do anything. The 255lph unit is major overkill for a Zetec. My Thunderbird had a 2.3 liter engine running 18 psi of boost and 36 lb/hr injectors (I think the Zetec is 17 lb/hr), and it had no problems at all with its stock 190 lph pump.

What pressure are you running at now? If you're running at more than a couple psi over stock, I'd try backing it down. Running too rich will definitely cause bogging and poor throttle response.

'99 Contour Sport V6 MTX