The Ultimate Engine Guide for the BMW B58. The BMW B58 engine is a turbo 3.0L inline-6 that debuted in BMW vehicles in 2016. From the factory, it produces a reasonable 322-382hp and 332-369 lb-ft of torque. However, with a few simple upgrades, the engine can produce 500+ horsepower. BMW’s B58 engine also offers an excellent blend of fuel economy and dependability. There’s a reason Toyota chose the B58 3.0 turbo in their iconic Supra.
Finally, this BMW 3.0L inline-6 engine has a lot to offer. When it comes to the B58, there is certainly a lot to unpack. How trustworthy is the engine? What are the finest B58 modifications for 500+ horsepower? How does it compare to other BMW engines such as the N54, N55, and so on? This page covers BMW B58 engine specs, performance, upgrades, dependability, and other topics.
B58 Engine Specifications
The B58 engine specifications are as follows:
The majority of the engine specifications for the B58 are normal for current turbo BMW engines. The N54 debuted in 2007 with a similar 3.0L turbo inline-6 engine that used direct injection and twin VANOS. All of this technology was used for the first time in a mass-production engine by BMW. The very basic design has stayed almost unchanged since then. The B58 engine is a 3.0L inline-6 turbocharged engine with direct injection and twin VANOS as well. Valvetronic (variable valve lift) was also implemented by BMW.
BMW also switched from an open-deck to a closed-deck block design. This design is ideal for high power and boost strength. The compression ratio has been increased from 10.2:1 on the N54 and N55 to 11.0:1 on the B58 3.0 turbo engine. All of these specifications enable the B58 to produce up to 382hp and 369 lb-ft of torque in the latest B58B30O1 engine.
It’s also widely acknowledged that BMW underrates their engines from the start. The B58 horsepower rating is actually closer to what it puts down to the wheels (although on a dynojet, which is typically generous). In any case, the main allure of the BMW B58 is its enormous potential for easy improvements and bolt-on changes. The engine is quite tuneable, and we’ll return to it later in the article.
Technical Update B58 (B58TU)
The technical update for the B58 engine in 2018 is an essential topic. These engines have engine codes that conclude in “1” and include the B58B30M1 and B58B30O1. In summary, the improved engine is known as the B58TU or B58TU1. Among the notable alterations to the B58TU are:
- Fuel system with higher pressure
- Timing chain redesign
- New cylinder head (with integrated manifold)
- Split-cooling
- Filters for particulate matter
Some of these adjustments improve performance, while others aim to improve dependability and emissions. The new 350 bar fuel system (vs. 200 bar on the earlier B58) provides a significant performance improvement. This higher pressure fuel system allows for higher E85 mixtures and more power before fueling modifications are required.
We could go on and on about the differences between the B58 and the B58TU. However, there is still much to discuss in this article. If you want to learn more about this topic, read this extensive B58 vs B58TU post.
BMW B58 vs N55
The B58 engine is the successor to the N55 engine, making the N55 vs B58 debate a hot topic. Both engines are powered by the same 3.0L inline-6 turbo engine. Despite BMW’s re-badging (with the debut of the B-series engines, the 40i badge practically replaced the 35i), they’re also in similar vehicles. Anyway, the majority of the similarities between the B58 and the N55 end there. Many design elements were taken in a different direction by BMW.
The air-to-water intercooler, closed deck block, forged steel crankshaft, and 5,000 PSI HPFP are a few significant differences. Again, these are only a handful of the many distinctions between the N55 and B58. We chose those few adjustments to emphasize one main point: the BMW B58 engine is stronger and more powerful. Specs on paper don’t always provide a complete picture, but this is also true in the actual world.
On the stock turbo, BMW N55 engines can produce around 400-425whp. Upgrade the N55 turbo (along with other supporting mods) and the engine can easily produce 500-600whp. Meanwhile, the B58 can produce 450-500whp with the stock turbo and 700-900whp with an upgraded turbo. It’s only fair to mention that few N55s have surpassed 750whp. However, the N55 does not produce as much power as the B58.
Finally, the N55 vs B58 comparison is intriguing. They’re both fantastic engines, but the B58 is unquestionably superior to the N55. The B58 engine not only has greater factory performance and overall potential, but it is also more reliable. More on these engines’ dependability in a bit. For the time being, let’s compare the B58 to another BMW engine that could be a more deadly foe.
N54 vs B58
BMW’s “legendary” N54 engine. If this engine isn’t famous for its incredible performance, it’s probably famous for its problematic (at best) reliability. The N54 was released about a decade before the B58. It has the same 3.0L inline-6 engine as the standard model, but it has twin turbochargers. The N54, like the B58, has a robust forged crankshaft. The open-deck block, on the other hand, is a disadvantage of the N54.
Even with standard turbos, the N54 produced 450-500whp and 550wtq. Upgraded twin turbos can produce 600-700whp, while single turbo conversions can provide 1,000whp. Many stock internal N54s have performed admirably at 650-700whp. Time will tell if the B58 holds up as well in the long run, but all signs point to a positive outcome.
The N54 is a high-performance engine, particularly for its period. However, time and technology have caught up, and the B58 now appears to be on par with the N54. Except that the B58 was far superior in terms of general design and dependability. While the N54 is a fantastic engine, it did have some early reliability and engine issues. With the N55, BMW sacrificed performance in order to improve reliability. The BMW B58 was used to bind everything together.
BMW B58 Reliability and Issues
It’s difficult to talk about engine reliability and difficulties with a new engine. The BMW B58 is only 6 years old, which is insufficient time to assess long-term reliability. However, the B58 has proven to be a dependable engine thus far. Some claim it is reliable by “BMW standards,” but we believe it is reliable by any standard.
Toyota, too, is employing the B58 3.0L turbo engine in their latest Supra vehicles. They often meet the greatest levels of dependability. Toyota allegedly conducted reliability and longevity testing on the B58 and made some minor adjustments. It’s unclear whether those improvements were passed on to the B58 installed in BMWs.
In any case, the B58 is shaping up to be a fantastic engine. Returning to the N54 for a moment, the engine had numerous faults that were apparent within the first 2-6 years. That hasn’t happened with the B58. Despite reliability concerns, the N54 delivers exceptional internal reliability. At standard power levels, the entire cylinder head, rods, rod bearings, pistons, rings, and so on are practically bulletproof. BMW’s timing chain is likewise quite good.
It is not uncommon for these engines to exceed 250,000 miles. They’re just expensive to get there because of additional issues like as oil leaks, coolant leaks, water pump failures, carbon buildup, fuel injectors, and so on. The B58 should have the same lifetime but with fewer ancillary system concerns.
Here’s a video we made that goes over the BMW B58 Common Problems, or you can keep reading below:
B58 Engine Issues
With the topic of reliability and longevity out of the way, let’s go deeper into BMW B58 engine difficulties. What are some of the probable problems with the B58? Are there any existing issues that appear to be widespread? Again, as a 6-year-old engine, we don’t have the complete picture. However, based on the limited data and previous BMW engine problems, it’s simple to identify a few areas. On the B58, keep an eye out for the following:
- Coolant depletion
- Oil spills
- Carbon accumulation
Below, we’ll take a quick look at each of these potential B58 issues. None of these faults are actually widespread in the sense that they affect a large number of B58 engines. Instead, these are some of the most prevalent areas where things go wrong.
1) BMW B58 Coolant Depletion
The B58 really has two coolant tanks and systems because of the air-to-water intercooler. A number of reports have surfaced about low coolant levels in the main tank. Some people have also reported low coolant levels in the secondary tank (for the air-to-water intercooler), albeit to a lesser extent. Anyway, we don’t think B58 coolant loss is a major issue right now.
The loss of coolant in the B58 has not been traced to any specific source or underlying problem(s). The cooling system is pressurized and airtight, so coolant loss should be minimal. The coolant cap, on the other hand, is intended to vent pressure in the event of over-pressurization. The B58 3.0L inline-6 coolant caps could just be too loose.
That’s our best assumption for the time being, because there aren’t any common difficulties associated with this odd coolant loss. It’s something to keep an eye on as the B58 ages, but it’s not a huge issue right now. Of course, if you notice overheating, apparent leaks, or coolant/oil mixing, there’s probably another problem that has to be addressed.
2) Oil Leaks in the B58 3.0 Inline-6
BMWs are notorious for having oil leaks. Oil leaks from the valve cover gasket, oil pan gasket, oil filter housing, and a few other places were common on the N54 and N55. Several BMW B58 engines are already experiencing similar oil leaks. However, they appear to be far fewer and further apart.
However, all cars, not just BMWs, are prone to leaks as they age and accumulate mileage. As a result, B58 oil leaks are projected to grow increasingly widespread as these vehicles age. Most oil leaks are caused by inexpensive gaskets that may be purchased for $10 to $50. The true killer, though, is labor. A B58 valve cover gasket costs around $50, but with labor, it can easily cost $800-$1,200 or more.
Continuing the pattern, the B58 appears to be far less problematic than previous BMW turbo engines. We doubt oil leaks will be as widespread as they were on the N54 or N55, but it’s something to keep in mind as the B58 ages.
3) Carbon Build-Up 3.0L Turbo
When it comes to gasoline direct injection engines, carbon buildup is a major topic. All engines produce some natural oil blow-by, which enters the intake tract. It then adheres to the intake valves and ports. Traditional port injection sprays fuel into the ports, and gasoline detergents naturally wash away any deposits.
Because direct injection sprays directly into the cylinders, no fuel is used to remove deposits. Carbon buildup from the deposits eventually causes misfires, power loss, and other performance difficulties. After 60,000 to 80,000 miles, the N54’s intake valves should be cleaned. The N55 was a good improvement, and it can travel 80,000-100,000 miles before carbon buildup becomes a problem. We believe the B58 will be even better.
Carbon build-up is commonly removed via walnut blasting. It involves the removal of the intake valves, which is a few hour process that can cost between $400 and $700. Many BMW shops charge significantly more, as we’ve heard numerous quotes of $1,000 or more.
In any case, carbon buildup isn’t a major concern. It rarely poses significant concerns to dependability or lifespan. Carbon buildup, on the other hand, can cause bothersome performance and drivability difficulties. The B58’s ability to tolerate carbon buildup will be determined over time. B58 walnut blasting is likely to be beneficial maintenance in the long run. But hopefully it’s only every 100,000 to 125,000 miles.
Best B58 Performance Enhancements
Okay, we’re finally getting to the most exciting part of the BMW B58 3.0L turbo engine, in our opinion. As previously stated, the B58 is a very powerful engine capable of producing a lot of power with simple upgrades. Among the best B58 bolt-on modifications are:
- Tune
- Intake
- Downpipe
- WMI Fueling
In this post, we’ll focus on some of the simplest power upgrades for stock turbo B58s. They’re among the most effective first-generation modifications for the 3.0 inline-6 turbo engine. Because the B58 is a very tuner-friendly engine, there are numerous upgrades available. The engine is capable of a lot, whether you want a “modest” 400-500whp on the stock turbo or a wild 800+whp upgrade.
When it comes to turbo upgrades and other substantial alterations, there’s a lot to cover. As a result, we’ll cover more of this in future publications. For the time being, let’s jump right in and talk about some of the greatest, simplest bolt-on upgrades for the BMW B58.
1) BMW B58 Customization
The single best performance upgrade for the B58 is a tune. Tuning not only provides enormous power gains, but it also serves as the foundation for creating additional power with various bolt-on mods. With standard pump fuels, a tune can provide gains in the 40-70whp range. When combined with an E85 mixture, a tune can produce gains of 70-100whp. That’s a lot of punch for a $500 tune.
The Burger Motorsports JB4 is one of our favorites. This piggyback tune is easy to install and includes 9 distinct maps for a variety of aims and needs. In contrast to flash tuning, there is no need to re-flash the DME. In a couple of seconds, you may switch between the factory tune, kill mode, and a valet/low boost map. It also enables water-methanol injection, E85 blends, back-end flash tweaking, and a variety of other features.
Finally, if you’re searching for a single performance mod for the B58, a tune is hard to beat. The dyno below shows a 2020 Z4 with a basic power output of 400whp and a monstrous 490whp with the JB4 tune and E40 fuelling. At the very least, impressive power gains.
Price: $529.00
Gains in power: 40-100+whp
B58 JB4 Tune – Best B58 Upgrades
2) B58 Performance Intake Modifications
An intake does not provide nearly the same amount of power or performance as the other modifications on this list. However, it’s still a fantastic B58 bolt-on mod that’s inexpensive and simple to install. It’s also a necessary upgrade for increasing power. Of course, when boost and power levels rise, the B58 requires more ventilation.
A performance intake’s simple purpose is to move more air more efficiently. To optimum performance, look no further than an open intake system. An intake may only gain 3-5whp with a simple adjustment. However, the advantages of a B58 intake upgrade grow as you add more mods and boost. Power increases of 7-10whp are feasible. Furthermore, intakes provide great sound, a clean engine bay, and a variety of other advantages.
Burger Motorsports offers some fantastic intake options for a wide range of B58 vehicles, including the Supra, F chassis, and G chassis variants. Whatever intake you go with, it’s a fantastic mod to pair with a tune for improved performance and sound.
Upgrades to the BMW B58 Downpipe
Outside of a tune, our favorite bolt-on mod for turbo engines is downpipe enhancements. The B58 downpipe connects directly to the turbocharger and contains a restrictive filter or catalytic converter. While these parts are great for emissions, they are extremely restrictive when it comes to increasing power and boost.
A B58 catless downpipe can provide increases in the 20-30whp range. It also improves turbo spool, engine/exhaust noises, and other aspects. The fundamental issue is whether a catless downpipe is legal. As a result, catted downpipes are a popular choice. They don’t offer quite as much performance, but should allow the B58 to pass emissions testing in most states. Expect power gains of about 10-20whp with a high-flow B58 catted downpipe.
Whether you’re looking for a catted or catless option VRSF has you covered. The catless downpipe for the F chassis M240i, 340i, 440i, 540i, 640i, and 740i is $299.99 while the high-flow downpipe is $479.99. We believe VRSF offers some of the best bolt-on upgrades for modern BMW engines, so look no further.
Price: $300-480
Power Gains: 10-30whp
Related : The Honda B16 vs B18 Engine Comparison
4) 3.0L Turbo Fueling & WMI
Fueling and water-methanol injection (WMI) could be an entire article of its own. As such, we’ll stick with some speedy notes to keep things moving. The B58 loves high-octane fueling when increasing boost. Normal pump gas is convenient, but it doesn’t deliver the best performance or power. Enter E85, race gas, and WMI.
In our opinion, E85 is the ultimate fueling solution. It burns cooler than gasoline and has a lower stoic. It greatly reduces the chance of pre-detonation, which means better ignition timing, more boost, and a lot more power. The downside to E85 is that it contains less energy per part when compared to gasoline. In turn, you need to flow more fuel which puts a lot of stress and demand on the fueling system.
The original B58 engines can handle about 20-30% E85, and the B58TU can handle about 30-40% on the stock fuel system and turbo. As shown in the dyno above, even a 40% E85 mixture can offer tons of power. Other great fueling alternative are race gas and water-methanol injection as they don’t put extra demand on the fuel system.
B58 Bolt-On Upgrades Summary
A tune, intake, downpipe, and better fueling can take the B58 a long way. These mods can push the B58 into the 450-500whp ballpark. That’s a lot of power for a 3.0L inline-6 engine on a factory turbocharger. Generally, the B58 can tolerate that power without serious reliability or longevity concerns.
It doesn’t stop there, either. The BMW B58 is capable of 600-700+whp on the stock engine with additional fueling mods and turbo upgrades. However, there are a lot of other mods to consider when shooting for that kind of power. It’s not for the faint of heart, but the B58 is a highly capable engine that can deliver immense power.
BMW B58 Engine Summary
The BMW B58 is a 3.0L inline-6 turbo engine that succeeded the popular and successful N54/N55 engines. It powers many flagship models like the BMW M240i, 340i, 440i, Z4 40i, and plenty more. With 322-382 horsepower from the factory the B58 delivers great performance. However, the great reliability (so far) and aftermarket potential is what really sets the B58 apart.
In its young age, the B58 is proving to be a reliable engine. There haven’t been any glaring issues or problems that appear very common. However, coolant loss, oil leaks, and carbon build-up are a few potential issues to monitor as the B58 ages. Regardless, the B58 is shaping up to be a reliable engine not only by BMW standards, but by any standards (including Toyota who is using the B58 in their Supra).
Those looking for extra power and performance won’t be disappointed in the BMW B58 3.0L engine. A few simple bolt-on mods can push the B58 to 450-500+whp on the stock turbo. If that isn’t enough there are already plenty of B58’s pushing 700+whp, and this platform still has a lot of growth and potential left.
