
Spool Split Fuel Surge Tank
Ships from the brand or distributor, usually in 3–7 business days
Make sure this fits your car
Fits: Universal: for B58 and S58 fuel and port-injection builds
- Shipping at real carrier rates
- 30-day returns on unused parts
- Fitment help before you buy
High-horsepower engines don’t just need more fuel — they need stable, predictable fuel control . The Spool Performance Split Fuel Surge Tank was designed specifically to solve the real problems that show up when direct injection and port injection are pushed hard. At high load, the factory high-pressure fuel pump for direct injection creates rapid pressure pulses on the low-pressure side of the system. When DI and PI share the same fuel supply, those pulses can travel through the fuel rail and cause unstable pressure at the port injectors , leading to inconsistent injector flow and tuning headaches. This is one of the most common causes of erratic PI behavior on high-power builds. Our split surge tank physically isolates the DI and PI fuel circuits .
Fits: Universal: for B58 and S58 fuel and port-injection builds
Brand: Spool Performance
Universal: for B58 and S58 fuel and port-injection builds
| Model | Chassis | Years | Engine | Fits |
|---|---|---|---|---|
| M140i | F20/F21 | 2016–2019 | Gen 1 B58 | |
| M240i | F22/F23 | 2016–2021 | Gen 1 B58 | |
| 340i | F30/F31/F34 | 2016–2019 | Gen 1 B58 | |
| 440i | F32/F33/F36 | 2017–2020 | Gen 1 B58 | |
| 540i | G30/G31 | 2017–2019 | Gen 1 B58 | |
| 740i | G11/G12 | 2016–2019 | Gen 1 B58 | |
| X3 M40i | G01 | 2018–2019 | Gen 1 B58 | |
| X4 M40i | G02 | 2019 | Gen 1 B58 | |
| 640i GT | G32 | 2018–2019 | Gen 1 B58 | |
| M340i | G20/G21 | 2019–2024 | Gen 2 B58 (TU) | |
| M440i | G22/G23/G26 | 2021–2024 | Gen 2 B58 (TU) | |
| M240i | G42 | 2022–2024 | Gen 2 B58 (TU) | |
| Z4 M40i | G29 | 2019+ | Gen 2 B58 (TU) | |
| GR Supra 3.0 | A90/A91 | 2020+ | Gen 2 B58 (TU) | |
| 540i | G30/G31 | 2020–2023 | Gen 2 B58 (TU) | |
| 740i | G11/G12 | 2020–2022 | Gen 2 B58 (TU) | |
| X3 M40i | G01 | 2020+ | Gen 2 B58 (TU) | |
| X4 M40i | G02 | 2020+ | Gen 2 B58 (TU) | |
| X5 xDrive40i | G05 | 2019–2023 | Gen 2 B58 (TU) | |
| X6 xDrive40i | G06 | 2020–2023 | Gen 2 B58 (TU) | |
| X7 xDrive40i | G07 | 2019–2022 | Gen 2 B58 (TU) | |
| 840i | G14/G15/G16 | 2019+ | Gen 2 B58 (TU) | |
| INEOS Grenadier | Station Wagon/Quartermaster | 2023+ | Gen 2 B58 (TU) | |
| M340i | G20/G21 | 2025+ | Gen 3 B58 (48V) | |
| M440i | G22/G23/G26 | 2025+ | Gen 3 B58 (48V) | |
| M240i | G42 | 2025+ | Gen 3 B58 (48V) | |
| M3 | G80/G81 | 2021+ | S58 (BMW M) | |
| M4 | G82/G83 | 2021+ | S58 (BMW M) | |
| M2 | G87 | 2023+ | S58 (BMW M) | |
| X3 M | F97 | 2020–2024 | S58 (BMW M) | |
| X4 M | F98 | 2020–2025 | S58 (BMW M) |
Not sure? Email sales@b58racing.com with your VIN.
- Ships from the brand or distributor, usually in 3–7 business days.
- Shipping is charged at the carrier's rate, shown at checkout. Orders over 70 lb ship by freight for a flat $99.
- Unused parts can be returned within 30 days. Some items are marked no-refund in their description.
Full details are on our shipping and returns page.
Guides for this part
B58 Fueling Explained: HPFP, LPFP, Port Injection, Flex Fuel and E85
The B58 fuel system has two pumps. The low-pressure pump (LPFP) in the tank feeds the high-pressure pump (HPFP) on the engine, which feeds the direct injectors. On a tuned car, the HPFP is usually the first wall, and eth
B58 HPFP Install: Gen 1 F-Chassis, Gen 2 B58TU and the GR Supra
The B58's high-pressure fuel pump (HPFP) bolts to the back of the valve cover, by the firewall. You disconnect the battery, bleed off the pressure by slowly cracking the 17 mm line nuts into rags, then remove the lines,
BMW S58 Mods Guide: M2, M3, M4, X3 M and X4 M Upgrades in Order
On an S58, start with a tune and cooling. These cars make a lot of power stock, and heat is what holds them back on hot days and back-to-back pulls. Next come downpipes and a tune built for them, then fuel: an ethanol an
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