The Ford Barn - View Single Post - Why Shimming A Fuel Pump Changes Fuel Pressure

ford38v8 · 01-20-2014, 08:53 PM

Barlea, That makes a lot of sense, and serves to illustrate why pressure is not dependent on volume and vice versa.

Another thought on Ted's spring on a scale... I wondered how JWL's "Ford Spec" could be so different, and realized that the 2 1/2 lbs is PSI, while Ted's scale measures Dry Weight, so apparently it takes 6 to 7 lbs pressure on the spring to produce 2 1/2 lbs PSI on the face of the diaphram.

01-20-2014, 08:53 PM	#15
ford38v8 Senior Member Join Date: Jul 2011 Location: SF Bay Area Posts: 6,635	Re: Why Shimming A Fuel Pump Changes Fuel Pressure Barlea, That makes a lot of sense, and serves to illustrate why pressure is not dependent on volume and vice versa. Another thought on Ted's spring on a scale... I wondered how JWL's "Ford Spec" could be so different, and realized that the 2 1/2 lbs is PSI, while Ted's scale measures Dry Weight, so apparently it takes 6 to 7 lbs pressure on the spring to produce 2 1/2 lbs PSI on the face of the diaphram. __________________ Alan