CLA 45 S

The Mercedes-AMG CLA 45 S represents pinnacle expression of compact performance engineering, launched 2020 as second-generation C118 chassis featuring world's most powerful series-production four-cylinder engine achieving unprecedented 416 horsepower (310 kW) at 6750 RPM with 369 pound-feet (500 Newton-meters) torque at 5000 RPM from 2.0-liter turbocharged M139 inline-four configuration. The revolutionary M139 architecture marks significant evolution from previous M133 engine, incorporating reversed orientation positioning exhaust manifold and twin-scroll BorgWarner turbocharger at rear between engine and firewall while intake system occupies front location optimizing thermal management and reducing intake air temperatures. Peak boost pressure reaches 30.5 PSI (2.1 bar) in S specification versus 27.5 PSI (1.9 bar) in standard CLA 45 configuration, with electronically-controlled wastegate providing precise boost management and roller-bearing turbocharger construction reducing mechanical friction enabling turbine speeds reaching 169,000 RPM delivering exceptional throttle response eliminating traditional turbo lag characteristics.

M139 engineering represents technological tour de force featuring closed-deck crankcase construction withstanding peak combustion pressures of 160 bar (2,320 PSI)—exceeding 840-horsepower Dodge Demon's 135 bar pressure—combined with forged steel crankshaft, forged aluminum pistons incorporating nanoslide cylinder coating technology reducing friction, dual fuel injection system combining direct injection operating 350 bar pressure with supplementary port injection optimizing mixture preparation across entire RPM range, and continuously variable VANOS-equivalent camshaft adjustment. The specific output achieves 208.9 horsepower per liter representing highest power density among series-production four-cylinder engines, surpassing Honda Civic Type R, BMW M2, and Volkswagen Golf R configurations through combination of extreme boost pressure, advanced materials engineering, and sophisticated thermal management systems. Each M139 unit undergoes hand assembly at AMG facility in Affalterbach, Germany under traditional 'One Man, One Engine' philosophy with individual master engine builder signature plate affixed to valve cover maintaining Mercedes-AMG heritage despite compact displacement.

Eight-speed AMG Speedshift DCT dual-clutch transmission delivers power to 4MATIC+ all-wheel-drive system featuring fully-variable torque distribution with AMG Torque Control managing individual rear-wheel torque vectoring through brake-based system optimizing rotation characteristics through corners. Standard configuration delivers predominantly rear-biased torque split with capability of transferring up to 50 percent forward during traction-limited conditions, while optional AMG Dynamic Plus Package introduces Race and Drift drive modes—Drift mode directing 100 percent torque rearward with ESP stability systems deactivated enabling controlled oversteer drift angles previously impossible with front-biased all-wheel-drive platforms. Performance hierarchy achieves 0-60 MPH acceleration in 3.9 seconds with electronically-limited top speed of 167 MPH, while AMG Driver's Package removes limiter enabling 168 MPH maximum velocity. Transmission calibration incorporates Multiple Downshift function enabling sequential multi-gear downshifts through steering-wheel paddles, Race Start launch control system, and aggressive shift mapping in Sport+ and Race modes maximizing acceleration capability.

Chassis architecture incorporates AMG Ride Control+ adaptive suspension featuring continuously variable dampers with three-stage adjustment spanning Comfort, Sport, and Sport+ configurations, while optional AMG Dynamic Plus Package adds stiffer spring rates, revised anti-roll bars, and dedicated Race suspension calibration. Braking system features 350-millimeter front discs with four-piston fixed calipers and 330-millimeter rear discs providing substantial stopping power, with optional AMG Performance brake package upgrading to larger 360-millimeter front rotors. Electronic stability systems include multi-stage ESP configuration allowing Sport and Track modes progressively relaxing intervention thresholds enabling aggressive driving techniques while maintaining safety net, combined with electronically-controlled limited-slip front differential managing torque distribution preventing understeer during corner-entry phases. Interior specification includes AMG Performance seats with integrated head restraints, Nappa leather and Dinamica microfiber upholstery, AMG Performance steering wheel with integrated drive mode controls, MBUX infotainment system featuring dual 10.25-inch displays, and AMG Track Pace telemetry application recording lap times, sector splits, and vehicle dynamics data enabling detailed performance analysis rivaling dedicated motorsport data acquisition systems previously exclusive to professional racing applications.