Its called fuel stack, and depending on the car its effect is manifested in the very first part of the run (60-330 feet). For simplicity, lets say the fuel line from the electric pump to the regulator holds 2 gallons (a fuel volume weight of about 12 pounds). Lets also assume the electric fuel pump has a built in regulator capable of maintaining 15 pounds of line pressure. If your car leaves with a force of 1g, the fuel in the line now weighs 24 pounds due to the centrifugal force of the forward moving car and the previously at rest fuel in the line. The electric fuel pumps built in regulator sees this pressure increase and bypasses all fuel back to the tank (or shuts off) until the pressure drops. Bigger fuel lines just aggravate this problem because there is more fuel in the line and it weighs even more under the very rapid acceleration that occurs in the start of the run. Because this problem is all over early in the run a lot of guys miss ever seeing the problem on the guage.
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