AC Schnitzer BMW M3 G80 / G81 Performance Upgrade Petrol SKU: 1100381370-36-c

This is a serious S58 upgrade, and the important detail is that SKU 1100381370-36 is specifically the AC Schnitzer Step II 610 PS package for the G81 M3 Competition Touring with M xDrive, including the AC Schnitzer exhaust system. 

🧠 Technical breakdown

Parameter	BMW M3 Competition G81	AC Schnitzer Step II
Engine	S58B30T0 3.0L twin-turbo I6	Same S58
Factory output	510 hp / 375 kW	610 hp / 449 kW
Factory torque	650 Nm	750 Nm
Power increase	-	+100 hp / +74 kW
Torque increase	-	+100 Nm
Fuel	-	Minimum 98 RON
Exhaust	BMW OEM	AC Schnitzer system included
ECU strategy	OEM	Additional AC Schnitzer control unit
Warranty	BMW	AC Schnitzer warranty stated at 36 months from initial registration

🔥 The clever part isn’t simply “610 hp”

AC Schnitzer’s philosophy is torque-first rather than chasing the biggest dyno number.

The additional control unit communicates with the factory engine management and modifies parameters associated with boost pressure, charge pressure and air mass, while retaining the BMW engine’s original protection strategies. 

AC Schnitzer also says its calibration reduces the modified parameters at high rpm above roughly 5,000 rpm, helping control thermal load during sustained high-speed operation. 

Think of the system as:

Driver demand → AC Schnitzer control unit → modified boost/air-mass strategy → BMW ECU → S58 → 8-speed M transmission → M xDrive

The result is not merely a higher peak number. The big transformation is the 750 Nm plateau: substantially more mid-range thrust and stronger acceleration when exiting corners or accelerating from rolling speeds.

🏎️ Why the S58 responds so well

The S58 already has an unusually strong foundation:

3.0L inline-six + twin turbochargers + forged internals + sophisticated thermal management + high-pressure direct injection

AC Schnitzer therefore doesn’t need to redesign the engine. Its approach is essentially to increase the operating envelope of the existing hardware while maintaining protective intervention.

That’s why this is fundamentally different from a simplistic “maximum boost” tune.

🔊 And this SKU includes the exhaust

This is where 1100381370-36 becomes considerably more interesting than the standalone performance upgrade.

The package includes an AC Schnitzer exhaust system, including:

• stainless-steel rear silencer
• sound pipe
• connecting pipe
• two exhaust flaps
• carbon end pipes, 110 mm outside diameter

So you’re getting a coordinated engine calibration + exhaust-flow + acoustic package, rather than simply adding an ECU box.

⚙️ The engineering philosophy

AC Schnitzer explicitly states that its objective isn’t extracting the absolute maximum possible output. Instead, it emphasizes robustness, torque delivery and engine/drivetrain longevity. 

That makes the character something like:

OEM M3 → 510 hp / 650 Nm
↓
AC Schnitzer calibration
↓
590–610 hp territory depending on variant
↓
750 Nm
↓
much harder mid-range acceleration + stronger corner-exit response

One important distinction: AC Schnitzer lists a 590 hp / 750 Nm G80/G81 upgrade separately, while 1100381370-36 is the G81 Touring Step II 610 PS package with exhaust. 

🏁 The verdict

1100381370-36-C is essentially an “OEM+ super-M3” philosophy.

It doesn’t turn the G81 into an extreme drag build. Instead, it takes one of BMW’s most capable modern powertrains and pushes it toward:

510 hp → 610 hp
650 Nm → 750 Nm
OEM exhaust → freer-flowing valved AC Schnitzer system
BMW calibration → AC Schnitzer torque-focused calibration

And that’s particularly compelling on the G81 Touring, because you end up with an extremely unusual combination:

family wagon practicality + M xDrive traction + S58 twin-turbo I6 + 610 hp + 750 Nm + AC Schnitzer acoustic character.

AC Schnitzer BMW M3 G80 / G81 Performance Upgrade Petrol SKU: 1100381370-36-c