The BMW B48 is a 2.0-liter turbocharged inline-four that anchors BMW's modular engine family, sharing its architecture, 500cc-per-cylinder displacement, and much of its parts catalog with the larger six-cylinder B58 and the smaller three-cylinder B38. Introduced in 2014 and still in production today, the B48 replaced the outgoing N20 and became the workhorse four-cylinder across BMW's lineup, delivering a broad output range from 180 hp all the way up to 302 hp in its hottest tunes.
Engineering & Specs
The B48 breathes through a single twin-scroll turbocharger, which pairs quick spool with strong midrange torque. Combined with BMW's TwinPower Turbo package—direct injection, Valvetronic variable valve lift, and Double-VANOS variable timing—it produces between 222 and 331 lb-ft depending on state of tune, with power ranging from 180 to 302 hp. Redline sits at a modest 6,500 rpm, reflecting its focus on flexible, torque-rich delivery rather than high-rpm theatrics.
- Configuration: 2.0L turbocharged inline-four
- Induction: Twin-scroll turbocharger
- Output: 180–302 hp
- Torque: 222–331 lb-ft
- Redline: 6,500 rpm
- Production: 2014–present
Which BMWs Used It
The B48 is found throughout BMW's modern range, both in longitudinal (rear-drive) and transverse (front-drive) applications. Notable fitments include:
- 2 Series: 230i
- 3 Series: 330i
- 4 Series: 430i
- 5 Series: 530i
- X models: X1, X2, and X3 in "30i" trim
- Z4: Z4 30i
Because the same displacement and family conventions span multiple platforms, the surest way to confirm which unit sits in a specific car is to run the chassis number through our VIN decoder. The closely related B46 is a variant of the same design, primarily used to meet certain emissions certifications.
Reliability & Ownership Notes
The B48 is widely regarded as a significant step forward from its N20 predecessor, addressing the earlier engine's timing-chain concerns with a more robust design. It has proven durable in daily service, though owners should stay on top of routine maintenance:
- Use quality oil and follow sensible, shorter oil-change intervals rather than the extended factory schedule.
- Watch for typical direct-injection carbon buildup on intake valves over high mileage.
- Address any oil-filter-housing gasket or valve-cover seepage promptly.
For buyers, a well-maintained B48 offers strong performance, excellent fuel economy, and abundant tuning potential thanks to its modular hardware.
Legacy
The B48 represents BMW's commitment to a unified, scalable engine philosophy, sharing DNA with the diesel B57 and the rest of the modular family. To explore how these engines relate across BMW's history, visit the BMW DNA encyclopedia.