BMW B48 Engine (Design, Problems & Reliability)

✔ This article has been fact checked.

The B48 is a 2L turbocharged inline-4 petrol engine from the BMW B-series modular engines; depending on the version, it generates 154-302 horsepower and 250-450 nm torque.

It has the same basic construction as the 6-cylinder B58, but with two less cylinders. The BMW B48 engine is the replacement for the 2.0L turbo N20 engine.

The B48 is most often found in BMW models with the suffixes 20i, 25i, 28i, and 30i. Some 35i cars from 2019 and later feature a higher power version of the B48. It may also be found in select Minis and in the fifth generation Toyota Supra.

The 2.0L + electric motor version of the B48 is featured in the 2021 Ward's 10 best engines list.

Table of Contents:

• Design

• Specs

• Problems & Reliability

• Is It a Good Engine?

• Power Limit

• B48 vs N20

• Variants

• Images

B48 Engine Design

The B48 is made differently from its N20 predecessor. The block and cylinder head are made of aluminium and are based on the N20. The N20 also has a twin-scroll turbocharger, direct injection, variable valve lift (Valvetronic), and variable valve timing (Dual VANOS).

The B48 is a member of the BMW engine family, which comprises 3-cylinder (B38/B37), 4-cylinder (B48/B47), and 6-cylinder (B58) engines with 500 cc displacement per cylinder.

Some of these engines are coupled with an electric motor to offer additional power and torque as required.

Engine Specs

• Manufacturer: BMW

• Production: 2014-present

• Configuration: Inline-four cylinder

• Displacement: 1,998 cc (122 cu in)

• Bore: 82.0 mm (3.23 in)

• Stroke: 94.6 mm (3.72 in)

• Valvetrain: DOHC

• Timing drive: Chain

• Compression ratio: 11:1

• Turbocharger: Single turbocharger, twin-scroll

• Fuel system: Direct injection

• Fuel type: Petrol

• Predecessor: BMW N20

• Engine oil capacity: 5.25 liters (5.55 quarts)

• Recommended engine oil: 0W-20, 0W-30, 5W-20, 5W-30

• Engine oil change interval: 10,000 miles or once a year

• Spark plug replacement interval: 40,000-60,000 miles

• Ignition coil replacement interval: 70,000-90,000 miles

Problems & Reliability

The BMW B48 engine is very reliable. It's still a newer engine, so only time will tell whether regular issues occur. BMW, on the other hand, seems to be improving in terms of reliability. The B48 and B58 are more dependable than the earlier N54, N55, N63, S65, etc.

Toyota also used the B48 engine in its Supra vehicles. They did tweak the design somewhat, but it still stands as a testament to the B48's durability.

Common Problems

Other than occasional coolant leak, the B48 engine does not seem to have many frequent problems.

There aren't a lot of common failure points in this engine. After 100,000 miles, problems with the cooling system, valve covers, and oil pan gaskets may become more prevalent.

Is the BMW B48 a Good Engine?

The BMW B48 is a four-cylinder turbocharged engine that was introduced in 2015 and has been used in a variety of BMW models since then.

It has a displacement of 2.0 liters and is part of BMW's modular engine family, which means that it shares some components with other engines in the lineup.

So, is the BMW B48 a good engine? Overall, it has received positive reviews from both drivers and industry experts. It has a reputation for being reliable and efficient, with many owners reporting few issues over the long term.

The B48 engine also has a strong power output, with some versions of the engine producing over 300 horsepower.

How Much HP Can a B48 Engine Handle?

In terms of how much horsepower the B48 can handle, it is generally considered to be a robust engine that can withstand significant increases in power. Many tuners have successfully pushed the B48 beyond its stock power levels without experiencing major issues.

The BMW B48 has been pushed to well over 300hp without many issues and with minor modifications.

However, as with any engine modification, it is important to be cautious and ensure that the necessary precautions are taken to avoid damaging the engine.

Is the B48 Better Than the N20 Engine?

As for whether the B48 is better than the N20 engine, it really depends on what you're looking for in an engine. The N20 is another four-cylinder turbocharged engine from BMW, it's the predecessor of the B48 engine.

Both engines have their own strengths and weaknesses, and which one is better for you will depend on your specific needs and preferences.

Overall, the BMW B48 is a solid engine choice that has proven itself to be reliable and efficient over the years.

It offers a strong power output and has the potential for further modification, making it a popular choice for drivers who are looking for a bit of extra performance from their vehicle. So, it can be a good engine for those who are looking for a strong and reliable engine for their vehicle.

Variants

This engine comes in 11 different variants, with 17 different torque outputs and 12 different power outputs.

302 hp Version

This engine includes a stronger crankshaft, larger main bearings, and reworked pistons with a 9.5:1 compression ratio.

The 302 hp B48 engines now have greater boost pressure from a larger turbocharger, which feeds compressed air via a reworked intake tract.

This engine was announced in May 2019 and would power the future MINI Countryman JCW, Clubman JCW, and JCW GP models.

B48B20 (2020)

• Power: 54 hp at 4,500-6,500 rpm

• Torque: 250 Nm (184 lb-ft) at 1,300-4,300 rpm

B48A20U1 (2020)

• Power: 176 hp at 5,000-5,500 rpm

• Torque: 280 Nm (207 lb-ft) at 1,350-4,200 rpm

B48B20M0 (2016)

This model was available in two versions, each with a different torque output.

• Power: 181 hp at 5,000-6,500 rpm

• Torque: 270 Nm (199 lb-ft) at 1,350-4,600 rpm

• Power: 181 hp at 5,000-6,500 rpm

• Torque: 290 Nm (214 lb-ft) at 1,350-4,250 rpm

B48A20M1 (2014)

This variant was available in four different power and torque outputs.

• Power: 189 hp at 5,000-6,500 rpm

• Torque: 280 Nm (207 lb-ft) at 1,250-4,600 rpm

• Power: 189 hp at 4,700-6,000 rpm

• Torque: 280 Nm (207 lb-ft) at 1,250-4,750 rpm

• Power: 189 hp at 5,000-6,000 rpm

• Torque: 280 Nm (207 lb-ft) at 1,350-4,600 rpm

• Power: 261 hp at 5,000-6,000 rpm

• Torque: 400 Nm (295 lb-ft) at 1,350-4,600 rpm

B48B20M1 (2019)

• Power: 194 hp at 4,500-6,600 rpm

• Torque: 320 Nm (236 lb-ft) at 1,450-4,200 rpm

B48B20O1 (2016)

• Power: 221 hp at 5,000-6,500 rpm

• Torque: 310 Nm (229 lb-ft) at 1,400-5,000 rpm

B48A20O1 (2015)

This version was available with three different torque outputs.

• Power: 228 hp at 5,000-6,000 rpm

• Torque: 350 Nm (258 lb-ft) at 1,250-4,500 rpm

• Power: 228 hp at 5,200-6,200 rpm

• Torque: 300 Nm (221 lb-ft) at 1,250-4,800 rpm

• Power: 228 hp at 5,000-6,000 rpm

• Torque: 350 Nm (258 lb-ft) at 1,450-4,500 rpm

B48O1ZIK

• Power: 241 hp at 4,500-6,500 rpm

• Torque: 400 Nm (295 lb-ft) at 1,600-4,000 rpm

B48B20O0 (2015)

• Power: 248 hp at 5,200-6,500 rpm

• Torque: 350 Nm (258 lb-ft) at 1,450-4,800 rpm

B48B20O1 (2016)

• Power: 255 hp at 5,000-6,500 rpm

• Torque: 400 Nm (295 lb-ft) at 1,550-4,400 rpm

B48A20T1 (2019)

• Power: 302 hp at 5,000-6,250 rpm

• Torque: 450 Nm (332 lb-ft) at 1,750-4,500 rpm

Images

Below are images of the BMW B48 engine.

Sources