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Best fuel pump for an LS swap

An LS needs about 58 psi of steady pressure, so the old mechanical pump is out. An in-tank electric pump is the best choice (it runs cooler and doesn't depend on gravity feed), with a 58 psi filter/regulator.

Sizing (Summit Racing, gasoline, pump free-flow rating):

Pump free flow Fuel-injected NA Fuel-injected w/ power adder
190 lph (50 gph) 500 hp 400 hp
255 lph (67 gph) 650 hp 500 hp
340 lph (90 gph) 850 hp 600 hp
470 lph (125 gph) 1,000 hp 800 hp

Free-flow ratings drop at EFI pressure, so check the pump's flow curve at 58 psi (plus boost if you're using a boost-referenced regulator), and make sure the pump sees about 13.5 V. Running E85? Choose an ethanol-compatible pump and plan for substantially more flow (see our E85 guide).

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