That Walbro pump is not meant for a returnless fuel system. They will work in the car but the pump is designed to have a constant voltage like a return style system. I have already purchased the pump Demon posted but have yet to put it in. There are many mustangs running this pump is excess of 400+ HP.
2002 Mustang GT
H&R, Bilstein, NX, K&N, Bassani, and Prochamber
03 Cobra wheels, Goodyear Eagles: 275 fronts, 315 rears
325HP and 433 ft-lbs at the wheels
Old Car:
2000 SVT #463/2150
Best #'s - 268.5HP and 275.8 ft-lbs at the wheels
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