BMW has a long history of producing powerful inline-six cylinder engines. Since the 1933’s, this engine layout has been a staple of the brand. Many renditions of the BMW inline 6 have been produced over the years, powering everything from base sedans and coupes to luxury SUVs and M Models.
History of BMW Turbo 6 Cylinders
The popularity of turbocharging, which emerged in the mid 2000s, ushered in a new era of BMW inline 6’s. Starting with the legendary N54 in 2006 and then N55 in 2009, BMW has offered a turbo six across their lineup for almost 20 years. The current generation motor, which was released in 2015, is referred to as the B58.
What is the B58 Engine?
The B58 carries on the lineage of inline six motors from BMW. It sits between smaller three and four cylinder (B38 & B48) and the larger N63 V8.
Engine Layout
The B58 is an inline-6 engine that displaces three liters. Inline engines have all their pistons in a row, sharing a single cylinder head, as opposed to “v” engines, which incorporate two banks of cylinders.
Turbocharging
The B58 utilizes a twin scroll turbocharger to force compressed air into the engine. Twin scroll turbos incorporate two veins on the exhaust housing, with each vein taking in exhaust from half of the engine’s cylinders. This technology leads to faster spool times and quicker power delivery.
Power Output
The power output of the B58 varies depending on its application. From the factory, it is available with 322 – 382 horsepower.
What Vehicles are Powered by the B58?
You can find the B58 engine across the BMW lineup and beyond. Here are some of the most common applications for this motor:
- M340i
- Z4 M40i
- X3 M40i
- X4 M40i
- M240i
- M440i
- Toyota GR Supra
B58 Tuning
Like its predecessors, the B58 is proving to be an incredibly tunable engine that responds very well to basic hardware and software upgrades.
Intake
An intake system is a great starting point when modifying a B58 Powered BMW. Upgraded intake systems will provide more free flowing air to the turbo, improve performance and provide an increase in audible turbo noise when driving.
Exhaust
An exhaust system improves the sound and look of your B58 powered car. Exhaust systems are available as catback (replacing everything after the catalytic converter), and axleback (generally just replacing the rear muffler). An upgraded exhaust can improve performance by allowing for better exhaust flow.
Downpipes
Downpipes are sections of the exhaust that come immediately after the turbo. A larger downpipe can provide impressive performance gains when paired with software. It’s important to note that the use of an aftermarket downpipe is not legal on public roads. This modification should only be done to dedicated track vehicles.
Software
Software upgrades are generally the best bang for your buck modification on turbocharged engines, and the B58 is no exception. Forced induction vehicles leave the factory with a lot of power left on the table, and a simple ECU tune unlocks it. Supporting mods like an intake and exhaust will yield even more gains from a tune.
Turbo Upgrades
After basic “bolt-on” mods like an intake, exhaust, and a tune are completed, the next step to more power is a turbocharger upgrade. There is a wide range of turbos available for the B58 engine.
B58 Hybrid Turbo
A hybrid turbo is created by increasing the size of the compressor wheel in the OEM turbo housing. Hybrid turbos allow for a dramatic increase in power potential while keeping the stock turbo location.
Stock Location Aftermarket Turbos
Larger turbos are available for the B58 that still retain the OEM manifold style and fitment. These units are a step between a hybrid and full frame turbo.
Full Frame Turbos
For serious high horsepower builds, a full frame turbo is the way to go. Unlike the prior options, full frame turbos require a custom manifold, reworked chargepiping, aftermarket exhaust, and much more in depth modifications to work properly. The trade off is massive power potential, so much so that engine internal upgrades may be required.
Built Motor and Beyond
If you are looking to push your B58 powered car to the limit, the stock engine internals will need to be upgraded. With that being said, the stock motor assembly is extremely robust, capable of handling 650-700 horsepower relatively safely. While those numbers are likely sufficient for most, going beyond that requires stronger forged pistons, rods, and upgraded cylinder head components like springs and valves.
B58 Tuning at Mark’s European
Whether you are looking for an ECU tune or a fully built track ready engine, Mark’s European is your destination for B58 performance in Post Falls and the surrounding area. Our team will help you compare options and find the right parts to get the most out of your vehicle. Give us a call and talk to our performance experts today!