mderoy340 said Your check valves are leaking. This is what I use with a dead head regulator and 3/8 fuel line from the tank for steady 1/4 mile WOT flow. Summit regulator is set to 6.5 psi OOTB. Carter Strip Super Mechanical Fuel Pumps M6270 Carter Strip Super Mechanical Fuel Pumps M6270 Click to expand...