What Engine Does a BMW 328i Have? N52 vs N20 Specs

The BMW 328i used two different engines depending on the generation: the N52B30 3.0-liter naturally aspirated inline-6 (2007–2011 E90) producing 228 horsepower and 199 lb-ft of torque, or the N20B20 2.0-liter turbocharged four-cylinder (2012–2016 F30) producing 240 horsepower and 258 lb-ft of torque^[1][2]. The 328i nameplate was discontinued after 2016 and replaced by the 330i.

BMW 328i Engine Specifications by Generation

BMW used the 328i badge across multiple 3 Series generations, but the engine underneath changed significantly over time. Understanding which engine powers your 328i depends entirely on model year.

Generation	Years	Engine Code	Displacement	Power	Torque
E90/E91/E92/E93	2007–2011	N52B30	3.0L I6	228 hp @ 6,500 rpm	199 lb-ft @ 2,750 rpm
F30/F31/F34	2012–2016	N20B20	2.0L I4 Turbo	240 hp @ 5,000 rpm	258 lb-ft @ 1,250–4,800 rpm

US and Canada specifications^[1][2]

Both engines earned Ward’s 10 Best Engines recognition—the N52 in 2006 and 2007, the N20 in 2012^[1][2]. But the driving experience differs substantially between generations. Similar engine evolution happened across BMW’s lineup, affecting models discussed in guides covering what type of oil a BMW 328i takes.

N52B30 Engine (E90 328i: 2007–2011)

The N52B30 represents BMW’s last naturally aspirated straight-six in the 328i. This 3.0-liter engine produces 228 horsepower at 6,500 rpm and 199 lb-ft of torque at 2,750 rpm in US-spec models^[1].

Technical Features

BMW engineered the N52 with several innovations that were groundbreaking at the time:

• Magnesium/aluminum composite block reducing weight by 22 lbs compared to the M54 predecessor
• Valvetronic (variable valve lift) eliminating the throttle butterfly
• Double-VANOS (variable valve timing) on both intake and exhaust camshafts
• Electric water pump replacing the belt-driven unit for improved efficiency
• Variable output oil pump reducing parasitic losses^[1]

The N52 revs to 7,000 rpm and delivers power in a linear fashion that enthusiasts describe as “silky smooth”^[3]. Dyno testing revealed the N52 puts down approximately 231 hp at the wheels—a 93% drivetrain efficiency rate that’s typical for naturally aspirated engines^[4].

The catch? That linear power delivery means the N52 doesn’t feel particularly quick until you wind it past 4,000 rpm. And if you’re wondering about BMW maintenance costs, the N52’s complexity can mean expensive repairs when things go wrong.

N52 Common Issues

The N52 earned a solid reliability reputation, but owners should watch for:

• VANOS solenoid failures causing rough idle and reduced power
• Valve cover gasket leaks around 80,000+ miles
• Water pump/thermostat failures (the electric water pump typically lasts 60,000–80,000 miles)
• VANOS bolt recalls affecting 2007–2013 models (155,627 vehicles recalled in 2023)^[1]

N20B20 Engine (F30 328i: 2012–2016)

When BMW redesigned the 3 Series for 2012, they made a controversial decision: replacing the beloved inline-6 with a 2.0-liter turbocharged four-cylinder. The N20B20 produces 240 horsepower at 5,000 rpm and 258 lb-ft of torque from just 1,250 rpm^[2].

Technical Features

The N20 packs BMW’s TwinPower Turbo technology into a smaller, more efficient package:

• Twin-scroll turbocharger for reduced lag and improved response
• Valvetronic (variable valve lift) carried over from the N52
• Double-VANOS (variable valve timing)
• High-pressure direct injection improving combustion efficiency
• Electric water pump and variable oil pump^[2]

Dyno testing showed the N20 producing 222 hp and 245 lb-ft at the wheels^[4]. That’s only 9 fewer wheel horsepower than the larger N52, but the N20’s torque advantage is massive—245 lb-ft versus 211 lb-ft at the wheels^[4].

The N20’s torque plateau stretches across the low and middle RPM ranges before tapering off as the turbo reaches capacity^[4]. This makes the F30 328i feel quicker in real-world driving despite the smaller engine. Understanding what a VANOS system does helps explain how BMW extracts this level of performance.

N20 Common Issues

The N20’s reputation took a hit due to one significant problem:

• Timing chain guide failures caused by defective plastic components that deteriorate and allow the chain to skip teeth, causing catastrophic engine damage^[2]
• A 2017 class action lawsuit alleged BMW knowingly sold vehicles with faulty timing chain guides
• Early production units (2011–2015) are most susceptible
• Symptoms include rattling on cold start and check engine lights^[2]

Later N20 engines (2015–2017) received revised timing chain components that largely resolved the issue. The N20 was replaced by the B48 engine in 2016, which the current 3 Series still uses today.

N52 vs N20: Which 328i Engine Is Better?

The answer depends on what you value in a driving experience.

Category	N52B30 (E90)	N20B20 (F30)	Winner
Character	Smooth, linear, revs	Punchy, torquey	Preference
Low-end torque	199 lb-ft @ 2,750 rpm	258 lb-ft @ 1,250 rpm	N20
High-RPM behavior	Pulls hard to 7,000	Tapers after 5,000	N52
Fuel economy (combined)	23 mpg	26 mpg	N20
Reliability	Proven, known issues	Timing chain concerns	N52
Sound	Classic inline-6 rasp	Subdued four-cylinder	N52

Based on owner reports and industry testing^[3][4]

Enthusiasts who chase redlines and appreciate mechanical character often prefer the N52. The inline-6 sound and linear power delivery feel more connected to BMW’s heritage. But for daily driving with occasional spirited runs, the N20’s torque advantage makes the F30 328i feel faster in most real-world situations^[3].

What Replaced the BMW 328i?

After 2016, BMW discontinued the 328i nameplate. The replacement is the 330i, which uses the B48 2.0-liter turbocharged four-cylinder producing 255 horsepower and 295 lb-ft of torque in current models^[5].

The B48 addresses the N20’s timing chain reliability concerns while adding approximately 15 hp and 37 lb-ft of torque. Current BMW 3 Series models continue using evolved versions of this engine architecture.

Key Takeaways

• The BMW 328i uses either the N52B30 3.0L inline-6 (2007–2011, 228 hp) or the N20B20 2.0L turbo-4 (2012–2016, 240 hp)—check your model year to identify which engine you have^[1][2].
• The N52 inline-6 delivers smooth, linear power and revs to 7,000 rpm with a classic BMW character, while the N20 turbo-4 offers significantly more low-end torque (258 vs 199 lb-ft) and better fuel economy^[4].
• Early N20 engines (2011–2015) have documented timing chain guide failures that can cause catastrophic damage—inspect around 80,000 miles if purchasing a used F30 328i^[2].
• The 328i was replaced by the 330i after 2016, which uses the B48 engine with improved reliability and more power (255 hp)^[5].

FAQs

References

1. Wikipedia. (2024). BMW N52. https://en.wikipedia.org/wiki/BMW_N52
2. Wikipedia. (2024). BMW N20. https://en.wikipedia.org/wiki/BMW_N20
3. E90Post Forums. (2023). N20 VS N52 Discussion. https://www.e90post.com/forums/showthread.php?t=1333888
4. BMW Blog. (2012). Dyno Results: 2012 BMW 328i N20 engine. https://www.bmwblog.com/2012/02/24/dyno-results-2012-bmw-328i-n20-engine/
5. Carbuzz. (2024). BMW 3 Series Sedan Generations: All Model Years. https://carbuzz.com/cars/bmw/3-series/generations/