{"product_id":"spool-stage3-lpfp-s55","title":"Spool Performance Stage 3 Low-Pressure Fuel Pump — S55","description":"\u003cp\u003e\u003cstrong\u003eSpool Performance Stage 3 low-pressure fuel pump for the S55 — F80 M3, F82\/F83 M4, F87 M2 Competition.\u003c\/strong\u003e 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.\u003c\/p\u003e\n\u003ch3\u003eWhat it is\u003c\/h3\u003e\n\u003cp\u003eA 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 1,200+ whp, and it's a complete drop-in replacement — no assembly or core return.\u003c\/p\u003e\n\u003ch3\u003eWhere it fits in the build\u003c\/h3\u003e\n\u003cp\u003eLow-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.\u003c\/p\u003e\n\u003ch3\u003eFitment\u003c\/h3\u003e\n\u003cp\u003eS55 — F80 M3, F82 M4, F83 M4 Convertible, F87 M2 Competition. Confirm your chassis in the selector.\u003c\/p\u003e\n\u003cp\u003eSourcing fueling with the tune? The \u003ca href=\"\/products\/fueling-kit-s55\"\u003eFueling Kit — S55\u003c\/a\u003e bundles the matched parts + calibration for 8% under à la carte.\u003c\/p\u003e","brand":"Spool Performance","offers":[{"title":"Assembled","offer_id":43280699260989,"sku":"SP-BMF8x-FP","price":1295.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0658\/2553\/8109\/files\/spool-stage3-lpfp-s55.jpg?v=1781742593","url":"https:\/\/essewerks.com\/products\/spool-stage3-lpfp-s55","provider":"Esse Werks","version":"1.0","type":"link"}