Every BMW enthusiast at one point has heard the argument, “BMWs are just an expensive way to lose even more money.” BMW has developed a stereotype among the misinformed or uninterested crowd as being unreliable and overrated. But, those in the know understand that that isn’t really the case. Sure, BMW has released some…temperamental engines over their 100-year history - looking at you, S85. But even the BMW engines that have a mood disorder still have character.
On the other side of the coin, BMW has also created some of the best internal combustion engines known to man. That isn’t just a subjective opinion, either. Since 1999, BMW has been awarded overall International Engine of the Year 5 times, many of which were consecutive. That award isn’t given out lightly and takes multiple criteria into account. While the exact formula for determining which engines are great and which ones aren’t isn’t exactly rigid, I’d think that it’s fair to say that performance, reliability, and importance/legacy are fair metrics. As such, those are the criteria that we’ll be focused on in this list.
If I was forced to pick the top 3 BMW engines of all time, I think I’d have a panic attack. That might be a little dramatic, but it seriously would be stressful. Prior to the 21st century, BMW produced some seriously good motors too. The M20, S14, S52, and M88 all come to mind as valid contenders. However, for the sake of keeping things current and succinct, we’ll be focused on the best post-2000 BMW engines in this guide.
Best Modern BMW Engine: S62
Okay, we might be pushing the definition of “modern” a bit with this one, as the S62 was technically produced from 1998 to 2003. However, we’re including it on the basis of its importance to BMW engines to follow and the precedent that it established at the time. The BMW S62 was the first V8 engine to be put in a car developed by the M Division.
While BMW had a solid reputation for building V8 engines spanning back to 1954, the M60 and M62 V8s released in 1992 brought the V8 back to modern BMW chassis. The S62 was a direct descendant of the M62 engine used in the E39 5-Series, featuring a larger displacement and elevated compression ratio. Its buttery, linear power delivery made it one of the smoothest engines on the market at the time and the perfect engine to pair with the E39 chassis. The S62 engine is unquestionably the primary reason that the E39 M5 is one of the most sought-after M cars of the 2000s.
BMW S62 Performance
As utilized in the 1998 through 2003 BMW E39 M5, the S62 produced 400 horsepower and 369 lb-ft of torque. The BMW Z8 also utilized an S62 engine that produced the same power and torque figures as the E39 M5 application. However, outside of the BMW camp, the S62 was put to use in a few other performance cars including the Ascari KZ1 and Ascari A10. In the KZ1, an S62, in highly modified and tuned form, produced a whopping 500 horsepower. Even more impressive was the modified S62 used in the A10 which produced a truly insane 625 horsepower. That is a testament to how well the S62 was designed.
The S62’s torque curve is one of the most impressive aspects of the engine’s performance, with torque coming on strong as early as 2,500 RPM, delivered smoothly and evenly all the way through 7,000 RPM. A broad torque curve was one of the primary objectives of the S62, which BMW designers unquestionably achieved. In comparison to the BMW M62 V8 that preceded it, the S62 featured a few key performance-increasing upgrades. Primary among them are more aggressive cast iron camshafts, higher capacity water pump, and double-VANOS, which we’ll cover a bit later.
BMW S62 Reliability
Regarding reliability, the S62 is known as one of the most dependable BMW M engines ever released. It is common to see E39 M5s with upwards of 150,000 miles on them running like a top to this day. Like any other engine, S62 reliability boils down to how well the engine is maintained over the years.
The S62 features some key reliability-enhancing improvements that allowed it to stand up to performance driving. While the entire S62 features entirely aluminum construction, it is nearly as strong as other cast-iron counterparts. The S62’s cylinder linings are chemically etched to reduce friction, in turn reducing internal temperatures. The S62 also uses the same forged crankshaft as the M62, making the rotating assembly pretty bulletproof. While the hypereutectic pistons aren’t as strong as forged ones, they can still withstand immense amounts of power.
Since the S62 was the first BMW engine ever to utilize dual-VANOS variable valve timing, it has been known to be occasionally problematic. As with most BMWs that utilize dual-VANOS, problems typically begin to arise around the 150,000-mile mark. Like the M62, the S62 is also known to have timing chain reliability issues at high mileage. S62 timing chains were designed to last 150,000 miles and should be changed at that interval.
BMW S62 Legacy/Importance
The S62 4.9L V8 established a few very important firsts for BMW. It was the first V8 engine used in a car developed by BMW’s M-Division, and also the first BMW engine to feature double-VANOS variable valve timing. Both of those firsts would go on to inform many BMW engine designs to come.
In the early 2000s, BMW needed to deliver a response to the Mercedes E50 AMG while also catering to North American demand for beefy V8s. The S62 was the perfect combination of class-dominating power and a fresh departure from the 6-cylinder formula that BMW typically stuck to. With the acclaim that the E39 M5 received from consumers and reviewers alike, BMW was satisfied that the V8 was the right choice. That would go on to inform the engine choices for many M models to come, including the S65 in the E90/92 M3 and even the newer S63 found in the F90 M5.
Double-VANOS is another extremely important innovation that the S62 ushered in as the new norm in performance BMW engines. Taking the initial VANOS design that only affected the intake valves and applying the same principle to the exhaust valves as well, BMW developed a solid variable valve timing setup that improved performance based on where you were in the rev range. Double-VANOS has become a pillar of BMW engine design and remains so to this day.
Best Modern BMW Engine: N54 Engine
So, as we have already established, the criteria for this list are performance, reliability, and legacy in no particular order. While the ideal situation would be for an engine to have a strong reputation for all three, sometimes it can only manage to score highly in two of the three categories. That is the case for the N54.
As BMW’s first mass-produced turbocharged gasoline engine, the N54 was bound to have some growing pains, and it certainly did. However, with the N54’s reliability issues came true magic in the performance department which would go on to cement its legacy as one of BMW’s most important engines. The N54 would also power some of the most popular and instrumental BMW models of the late 2000s and early 2010s, including the BMW E92 335i, E82 135i, and E60 535i.
The N54’s primary characteristic is its insane power potential. In comparison to most other BMW engines that preceded it, the N54 required relatively few modifications to nearly double its stock horsepower figure, all on stock internals.
BMW N54 Performance
This is unquestionably the category where the N54 shines. On paper, the N54 seems like a somewhat underwhelming engine. 300 horsepower from a twin-turbo 3.0L inline-6 doesn’t seem like anything to write home about. In addition to being underrated by BMW by 20-30 horsepower, the N54 has some promising characteristics from the factory that made it a force to be reckoned with on the street.
The N54 features small stock turbos, a longer stroke, and comparably high compression compared to other competitors, making it a demon low in the rev range. The massive amount of low-end torque makes it an extremely strong competitor in roll races and from a dig. Beyond the N54’s already impressive factory performance, the 3.0L twin-turbo truly comes alive with aftermarket support. With basic bolt-on modifications and a tune, it is easy to reach the 400-horsepower mark. With fueling modifications, you can get close to 500 horsepower without any other internal modifications.
Strength is a defining characteristic of the N54, with a block that can withstand upwards of 700 horsepower despite its open-deck design and aluminum construction. Beyond just the block strength, the N54 also features a forged crankshaft and forged piston rods making the rotating assembly nearly bulletproof. While the pistons are still cast, they can withstand their fair share of abuse.
Overall, the N54 is one of the highest-performing engines that BMW has ever made when paired with aftermarket modifications. The N54 is often referred to as the German 2JZ due to its power potential and strength.
BMW N54 Reliability
While the N54 might be an extremely strong engine internally, it is typically the supporting engine components that let the 3.0L twin-turbo 6-cylinder down. Cooling system issues, fuel system problems, and turbo failures all contribute to the N54’s reputation for being a temperamental beast.
Water pumps and thermostats tend to only live short lives in N54-powered cars. The plastic water pump's construction cracks over time and has a tendency to leak coolant all over the place. Some N54 owners claim to have issues with their water pumps and thermostats around every 60,000-mile interval. Sometimes even sooner. Unfortunately, you’ll just have to stay on top of maintenance and keep a diligent eye on engine temps and potential leaks.
Beyond the cooling system, the N54 has also struggled with reliability in the fueling department. In its initial stages, the N54 high-pressure fuel pump was a serious sore point for many E90 335i drivers. The pump was such an issue that BMW issued a recall, replacing many of the fuel pumps with a better-designed ones. As a result, many N54s no longer experience fueling issues in the same way.
The stock N54 turbos were also problematic in their early stages, with high and continuous boost pressure resulting in rattling wastegates. While wastegate rattle is still a problem with N54s running factory boost levels, especially around the 100,000 mark, it is a far more common issue with those running an aftermarket tune with increased boost pressure.
While the N54 isn’t known for its reliability, there were steps that you could take to avoid many of the issues listed above. In fact, BMW addressed the fuel pump and wastegate rattle issues directly through recalls and factory repairs.
BMW N54 Legacy/Importance
It is impossible to ignore the BMW N54’s importance in informing BMWs modern engine design philosophy as a whole. As BMWs first mass-produced turbocharged engine, the N54 proved to be a favorite among enthusiasts and those in the automotive industry. As a result, BMW carried forward with producing turbocharged 6-cylinder engines, resulting in some of the best engines the company has made overall. While BMW had some issues to iron out with the N54, it played a vital role in testing how a twin-turbo V6 would operate in actuality.
BMW obviously had the performance aspect of the N54 down. With the engines to come, BMW focused on the reliability aspect of their turbo 6-cylinder formula. The BMW N55 engine that succeeded the N54 had a much better reputation in terms of overall reliability. That trend continued into the late 2010s with engines like the N63 and B58. With those newer turbo 6-cylinders, BMW has been able to bridge performance and reliability to build some of the best engines ever made. The N54 served as the basis for the future of turbocharged BMW engines.
Best Modern BMW Engine: B58
While the B58 engine didn’t arrive on the scene until 2015, it has since become, in many minds, the best engine that BMW has ever released. We just finished talking about the N54 which launched the mass-produced turbocharged 6-cylinder formula. The B58 serves as the compilation of everything that BMW has learned about that manufacturer-defining formula and it very nearly reaches perfection.
While the N55 middle child was certainly more reliable than the N54, the B58 is leaps and bounds more reliable than both the N54 and N55 due to some crucial design changes. In addition to the reliability-improving design changes, BMW also found a way to squeeze a lot more power out of the B58 as well.
The B58 occupies a very important role in the modern BMW lineup as one of the main engines that span the BMW range. It has powered, and continues to power, everything from the F30 340i to the G05 X5. It has proven to be such a good powerhouse that it is even in demand from other manufacturers, including Toyota who uses the B58 in the A90 Supra. Its versatility is one of the most impressive aspects of the B58, as it truly feels at home in every BMW that it is dropped into. The B58s power delivery truly proves that BMW is nearing engineering perfection.
BMW B58 Performance
In comparison to the turbocharged straight-6 engines that BMW has produced in the past, the B58 is truly a monster. Even the least powerful B58B30M0 variant of the B58 produces 322 horsepower and 332 lb-ft of torque. The increased performance comes primarily from the B58’s 20% increase in boost pressure over the N55. The B58 also features a higher 11.0:1 compression ratio and slightly increased displacement.
With the implementation of twin-scroll turbochargers, as used on the N55, the B58 never lacks in power or torque. Despite being a turbocharged engine, the B58 delivers power linearly without any significant lapses in power or torque at any rev range. That linear character is a defining characteristic of a BMW straight-6 and one that isn’t lost with the B58.
The B58’s stock twin-scroll turbocharger is good for around 425 horsepower, allowing for enthusiasts to have a little fun before swapping out the turbo for higher horsepower goals. Like the N54 and N55, it is extremely easy to breach the 400-horsepower barrier with a B58. In fact, simple bolt-on mods like an upgraded intake, tune, and downpipe can yield close to 500 horsepower.
Due to the B58’s robust design, it can handle as much, if not more, horsepower than a stock N54 or N55. While there are some lunatics out there pushing B58s beyond the 800 horsepower mark, the generally accepted safe limit for B58 internals is somewhere around 650-700 horsepower.
BMW B58 Reliability
As we’ve already hinted at, the B58 is likely the strongest turbocharged 6-cylinder that BMW has ever made. While we only have 7 years to gather real-life proof of that fact, the B58 has held up extremely well so far. Much of the B58’s added reliability can be attributed to design alterations from the previous N55.
Both the N54 and N55 feature open deck designs which is less than ideal if you have high horsepower aspirations. The B58, on the other hand, features a closed deck design, making it the better engine for big power and boosting reliability overall. Additionally, the B58 uses a heat encapsulation system around the engine, drawing heat away from the engine and storing it after the vehicle is turned off. This prolongs the cooling process of the engine which reduces the negative effects of repeated heat cycles on the internal components.
Like with any other BMW engine, routine maintenance is the ultimate key to B58 reliability. With that being said, there are a couple of issues that are still prevalent through the current generation of turbo straight-6. VANOS solenoid issues are still expected to be an issue with the B58, as solenoid failure is somewhat inherent in their design. While it isn’t a common problem for the B58 yet, VANOS solenoids are expected to last around 100,000 miles. There aren’t any repeat issues with the B58 that have affected a great deal of them yet. While the B58 is a relatively new engine, it is very impressive on the reliability front so far.
BMW B58 Legacy/Importance
While I’m sure that the B58 isn’t the end of the line as far as great turbocharged BMW straight-6s are concerned, the B58 really does flirt with perfection. It’s hard to see how BMW can outdo themselves. Just as the N54 is the engine that started the modern turbo-six phase in the BMW saga, the B58 represents the formula at its peak. The combination of reliability and performance that the B58 provides is emblematic of how far BMW has come and what they are able to achieve. That definitely makes it one of the most important modern BMW engines and one of their most important engines overall.
Best Modern BMW Engines Summary
Throughout BMWs history, they have continually been lauded for their ability to put together a fantastic engine. Some of the company’s most defining engines, like the M20, M50, S54, and M88, were developed prior to the turn of the century. However, BMW used much of their knowledge from those legendary engines to develop some of their best engines post-2000.
The BMW S62 V8 confirmed that the Bavarian mark could do more than straight-6s. While BMW had a history with 8-cylinder engines, the S62 stood above the rest in terms of performance and innovation. Being the first V8 in an M car, the first engine to feature double-VANOS, and an engine that would go on to inform the rest of BMW’s now massive V8 lineup, the S62 deserves its spot on this list.
The N54 stands out for its truly impressive performance, aftermarket modifiability, and its importance as the first in a long series of turbocharged inline-6s for the brand. While the N54 might not have done it best, it cemented BMWs turbocharged formula that would dominate from the 2010s to the present day.
Continuing and perfecting the recipe that was established by the N54, the BMW B58 is the most refined, versatile, powerful, and reliable turbocharged inline 6-cylinder that BMW has ever made. The success of the B58 goes to show that BMW has evolved from the early 2010s and has come a long way in designing reliable and powerful combustion engines.
Obviously, this list is subjective and short, with quite a few valid contenders not mentioned. However, the engines mentioned above set themselves apart due to their mix of performance, reliability, and, perhaps most importantly, their influence on other engines that succeeded them.
BMW has developed quite a few amazing engines in the modern era, which is your favorite? If you didn’t see your pick, let us know what BMW engine should have been on this list.