The engines of the BMW M3 & M4.

What was the most difficult thing to engineer at the S58?

Berti: Shaving off weight from the crankshaft while maintaining the high power output and torsional rigidity was a pretty ambitious task.

How much did the crankshaft weigh from the previous M models?

The already lightweight S55 crank weighs about 21kg - so the new one is almost 2kg lighter while being capable of even higher power outputs.

Does this or any other M car feature cylinder deactivation? If not, would you ever consider it in a new model?

With our Valvetronic valve timing system, optimum fuel efficiency across the entire rpm range is achieved. Hence, there is no need to use an additional cylinder deactivation.

What DOT oil do you recommend for combined track and daily use?

The same as all current BMW M vehicles. Please, refer to your user's manual for detailed specifications.

Should you change the bearing shells after a certain amount of kilometers?

In principle, the bearings are designed to last a complete engine's lifetime.

How many kilometers does it ideally take before you can go flat out?

Berti: The regular recommended 2,000 km break-in period ensures full power and perfect wear for all components of the drivetrain.

Which casting process is used to manufacture the components?

The main engine internals - crankshaft, pistons, conrods, camshaft - are all forged parts. Other parts like cylinder heads, engine block, oil pan are different cast production methods.

Are the engine components different for the regular and competition models?

No, there is no difference with regards to the hardware.

Is there any use of plastic in the S58, if so why?

Some parts are made of plastic - e.g. the oil pump's suction pipe - the reason being the use of the most appropriate material for any given purpose and package situation.

Why are engines covered with a plastic on the top? What is the benefit?

Besides the visual impact the cover mainly serves as an acoustic absorber.

What benefit does actively cracking the big end for install have vs cutting it?

The natural surface created by cracking the big end bearing is a quite effective method to achive the perfect match for both parts.

How do you ensure the inner surface of the piston rod stays smooth when it is cracked?

Basically, that is the trick of it. It is supposed to be a rough surface to create the perfect match for both parts. The bearing itself is being finished after the cracking process.

What is the function of valve seat pockets?

The valve seat pockets prevent the valves from touching the piston.

How long does the ceramic layer on the pin last in km's?

It is designed to last an engine's lifetime.

What main heritage features of former inline-6-cylinder engines are still available on the BMW M3 and M4 engine?

Despite all parts being new, the philosophy of a BMW inline-6 is still the same - providing a wide power band combined with a perfectly balanced engine.