Engine Specifications: BMW’s Staple Turbocharged 2.0L Powerplant
The BMW B48 engine stands at the core of BMW’s modern performance portfolio — a 2.0L inline-four turbocharged engine that blends efficiency, engineering modularity, and tuning potential into a single powerplant. Since its debut in 2014, the B48 has powered a wide range of BMW and MINI models, delivering solid factory performance and exceptional headroom for aftermarket modification.
This article breaks down the full technical specifications of the BMW B48 engine, covering architecture, performance figures, and key internal components — all written from the perspective of tuners and builders who want to understand what makes this engine platform so capable.
🔧 Core Engine Specs: BMW B48 Overview
| Specification | Detail |
|---|---|
| Engine Code | B48B20 (Gen 1) / B48B20O1, B48A20O1 (Gen 2) |
| Engine Type | Inline-4, turbocharged |
| Displacement | 1,998 cc (2.0L) |
| Bore x Stroke | 82.0 mm × 94.6 mm |
| Compression Ratio | 10.2:1 (varies slightly by model/tune) |
| Block & Head Material | Aluminium alloy |
| Valvetrain | DOHC, 4 valves per cylinder, Valvetronic & VANOS |
| Turbocharger | Twin-scroll turbo, integrated exhaust manifold |
| Fuel System | Direct injection (up to 350 bar pressure) |
| Redline | ~6,500 RPM |
| ECU | Bosch MG1 (Gen 2) / Bosch MEVD (Gen 1) |
🚗 Power Output Across Models
BMW has deployed the B48 across multiple model ranges with different ECU calibrations and boost targets. Here's how it varies from model to model:
| Model | Peak Horsepower | Peak Torque (Nm) |
|---|---|---|
| BMW 320i (F30/G20) | 181–184 hp | 270–300 Nm |
| BMW 330i (F30/G20) | 248–258 hp | 400–420 Nm |
| BMW 330e (G20 PHEV) | 288 hp (w/ electric boost) | 420 Nm |
| BMW M135i xDrive (F40) | 302 hp | 450 Nm |
| Toyota Supra 2.0 (J29) | 255 hp | 400 Nm |
⚙️ Modular Design & Shared Architecture
One of the standout features of the B48 engine is its modular design philosophy, which it shares with the B38 (3-cylinder) and B58 (6-cylinder) engines. Each cylinder in the modular lineup is based on a 500cc displacement, with shared components like pistons, rods, timing gear, and ECU architecture.
This modularity allows for:
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Simplified production and servicing
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Cross-compatibility of performance parts
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Easier scaling for different platforms (FWD, RWD, AWD)
🧰 Internal Components & Tuning Considerations
From a tuner’s perspective, the B48 comes with some solid internals — especially for mild to moderate power upgrades.
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Pistons & Rods: Cast pistons with forged connecting rods (stronger in Gen 2 variants)
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Crankshaft: Forged steel
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Turbocharger: Twin-scroll unit (BorgWarner or Mitsubishi, depending on model)
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Cooling: Gen 2 engines often feature integrated water-to-air charge coolers, ideal for tuning
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Fueling: High-pressure direct injection (HPFP upgrades recommended beyond Stage 2+)
These components support:
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Stage 1 tunes safely on stock hardware
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Stage 2+ builds with supporting mods (intake, downpipe, intercooler, charge pipe)
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Stage 3 with turbo upgrade, upgraded fueling, and tuned ECU/TCU
📈 Factory vs Tuned Performance (Typical Gains)
| Tuning Stage | Required Mods | Expected Gains |
|---|---|---|
| Stage 1 | Stock hardware, RON 97+ fuel | +40–60 hp / +60–90 Nm |
| Stage 2 | Intake, downpipe, intercooler, tune | +70–100 hp / +100–140 Nm |
| Stage 3 | Hybrid turbo, fueling, full bolt-ons, custom tune | +100–160 hp / +140–200 Nm+ (build-dependent) |
Figures vary based on engine generation, fuel quality, and dyno conditions.
🔍 Real-World Applications
The B48 powers a wide range of BMWs, including:
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G20 330i / 320i / 330e
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F30 320i / 330i
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F40 M135i / 128ti
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G30 520i / 530i / 530e
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G29 Z4 sDrive 20i / 30i
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Mini Cooper S / JCW
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Toyota Supra 2.0
Whether it's RWD, xDrive AWD, or even front-wheel-drive layouts, the B48’s adaptability is a big part of its success.
🧊 Closed Deck Block
One of the most significant engineering advancements of the B48 engine over its predecessors — including the N20 — is its closed-deck block design. Unlike the open-deck configuration of the N20, which leaves more space around the cylinders and limits structural rigidity under high boost, the B48’s closed-deck architecture offers reinforced support around the cylinder walls. This not only increases the engine’s tolerance to higher cylinder pressures — crucial for turbocharged applications — but also improves overall thermal stability and durability during prolonged high-performance use. For tuners and enthusiasts, this means the B48 is inherently more capable of handling aggressive upgrades like hybrid turbos, ethanol blends (E30/E85), and elevated boost targets without compromising reliability. It’s a platform truly built with the future of performance tuning in mind.
💡 Final Thoughts: Why B48 Specs Matter for Tuners
Understanding the specifications of the B48 engine gives tuners and enthusiasts the blueprint to build smarter, faster, and more reliable BMWs. Whether you're optimizing for daily drivability, spirited back-road runs, or full-on track days, the B48's engineering supports a wide tuning spectrum. Contact us here, and get your tuning journey started right away!
At RPM Performance, we specialize in BMW B48 tuning, bolt-on upgrades, and full-stage builds. Every mod we offer is tested, data-backed, and built to bring out the best in your BMW — safely and consistently.