Fuel System RSS

The Mercedes-AMG GT family runs the M178 — the dry-sump variant of AMG's 4.0L twin-turbo V8. Like its wet-sump sibling (the M177), the M178's stock high-pressure fuel pump is the first bottleneck when pushing beyond factory output. This guide covers HPFP upgrade options specifically for the AMG GT, GTS, GTC, GTR, and Black Series. M178 vs M177 — What's Different? The M178 shares the same 4.0L twin-turbo V8 block architecture as the M177 but uses a dry-sump lubrication system instead of wet sump. This allows the engine to sit lower in the chassis for a lower center of gravity —...

The stock high-pressure fuel pump on the Mercedes-AMG M177 4.0L V8 BiTurbo is the first component to hit its limit when you push beyond factory power. Whether you're running a Stage 2 ECU calibration, upgraded turbos, or ethanol-blended fuels, the OEM HPFP cannot deliver enough volume to maintain stable rail pressure — and that means lost power, misfires, or worse. This guide covers everything you need to know about upgrading the HPFP on the M177 platform: what the stock system's limits are, how 250bar and 350bar kits compare, which models fit, and what supporting modifications you need. Why the Stock...

The M177's stock fuel system is well-engineered for factory power levels but runs into hard limits once you push past Stage 2. This guide covers exactly when the stock fuel system runs out, what to upgrade, and how much each component costs — from low-pressure fuel pump upgrades through full port injection systems. Stock Fuel System Architecture The M177 uses a direct injection (DI) fuel system with the following factory components: High-pressure fuel pumps (HPFP): Two cam-driven piston pumps, one per bank, generating up to 200+ bar (2,900+ PSI) of fuel pressure Low-pressure fuel pump (LPFP): Single in-tank electric pump...