Spool Performance Stage 3 Low-Pressure Fuel Pump — B58
Spool Performance Stage 3 low-pressure fuel pump for the B58 — the in-tank side that keeps a Stage 3 build fed. A big high-pressure pump is only as good as what feeds it; the factory in-tank (low-pressure) pump runs out of duty on E85 and high boost, and rail pressure drops up top. Spool's Stage 3 adds a boost-activated secondary in-tank pump, roughly doubling low-pressure flow.
What it is
A twin-pump in-tank upgrade: the factory pump plus a second pump that switches on under boost (boost/Hobbs-switch activated), so cruise stays factory-quiet and the system only ramps when you're on it. Spool rates it to support 1,000+ whp. Built around your bucket — send-your-core, bucket trade-in, and new-build options are available; ask which suits you.
Where it fits in the build
Low-pressure (in-tank) side; it pairs with an upgraded high-pressure (DI) pump so the HPFP is never starved. We tune the engine to the fuel system.
Fitment
B58 — M240i (F22), 340i (F30), 440i (F32), M340i (G20), M440i (G22), Z4 M40i (G29), M240i (G42). Confirm your chassis in the selector.
Sourcing fueling with the tune? The Fueling Kit — B58 bundles the matched parts + calibration for 8% under à la carte.


