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BMW Found a Way to Save Its M Six-Cylinder Without Going Hybrid

By Karl Furlong Autoblog

Updated May 8, 2026 7:41 AM

The S58 inline six-cylinder engine in some of BMW's most engaging M cars needs no introduction. Produced since 2019, this charismatic turbocharged mill has powered everything from the M2 to the M3, M4, and even the mighty BMW 3.0 CSL. But performance engines like this one are threatened by ever-stricter emissions regulations. BMW knows how important six-cylinder power is for these M cars, though, so it will be introducing a revised version of the S58 in mid-2026 that meets the European Euro 7 standard and boasts better efficiency-without affecting power and performance in any way.

M Ignite Pre-Chamber Ignition System

Known as the "M Ignite" system, the innovative design update is based around a new pre-chamber in the cylinder head. Connected to the cylinder's main combustion chamber by overflow openings, the pre-chamber has its own spark plug and ignition coil. Effectively, this means the engine has two ignition systems.

"At low and medium revs, the conventional spark plug in the main combustion chamber fires before the spark plug in the pre-chamber," says BMW M. "At higher revs and loads, the pre-chamber ignition takes over the lead role. In this process, a part of the fuel-air mixture, which is channeled into the pre-chamber through the openings, is ignited there. The flames generated as a result then exit the pre-chamber at around the speed of sound."

At low and medium revs, a conventional spark plug fires before the spark plug in the pre-chamber. BMW BMW

At higher revs, the pre-chamber ignition takes over the lead role. BMW BMW

Following this, "ignition jets" ignite the mixture in the main combustion chamber, which occurs above the piston at multiple points at the same time. This leads to much higher combustion speeds. Furthermore, BMW has added new exhaust gas turbochargers with a variable turbine geometry-a first for the S58.

If you're worried that these changes will affect the engine's soundtrack, think again. BMW M claims that the dual ignition systems actually create a throatier sound at high revs, which you can listen to here.

Track Days Just Got More Affordable

Heavy loads and high revs typically have a drastic effect on the gas mileage of turbocharged cars. This will be obvious in a track environment, where your M2 or M3 will use a lot more gas. However, BMW says the M Ignite system will result in substantially lower consumption under high load.

While few specific claims were made, the company published a figure for the M2 of 10.2 liters per 100 km, which translates to 23 mpg. The current M2 gets 19 mpg combined, so if the 23 mpg is a combined figure and based on EPA standards, that would be a noticeable improvement. More realistically, a 1 to 2 mpg improvement is on the cards.

"With M Ignite, we are transferring combustion engine technology from motorsport to our high-performance road vehicles," said Alexander Karajlovic, Head of Development at BMW M. "With M Ignite in the S58, we are offering our customers a purist combustion engine without hybridization that meets our high standards for an M powertrain."

The M3 and M4 will be the first models to benefit from the upgraded S58 engine in July 2026. A month later, the M2 will receive the new M Ignite system. All will have the same 3.0-liter displacement and power outputs as the existing models.

What It Means

Mercedes-AMG found out the hard way that simply moving to a smaller-capacity, hybridized setup to achieve better emissions wasn't the solution fans wanted for models like the C63, which had always had a V8. Rather than go the same route, BMW has re-engineered its classic straight-six for another generation, while retaining the character of these smaller M cars. BMW M boss Frank van Meel promised that keeping the six-cylinder and V8 M engines around was a priority, and the new M Ignite system shows he's making good on that.

This story was originally published May 8, 2026 at 7:30 AM.