Built alongside the CLA-class and the European-market A-class hatch, the GLA45 AMG gets the same eye-watering 355 hp and 332 lb-ft of torque as the brand's CLA45 AMG. That's 147-hp more than the GLA250 offers, and is enough to propel the compact SUV from 0 to 60 mph in just 4.8 seconds. The 2-liter AMG I-4 is a high-strung unit that makes the most of its displacement and is helped by some clever technology. The twin-scroll turbocharger makes the biggest difference here: it permits quicker buildup of charge pressure using exhaust back-pressure, exhaust-gas pulse, and exhaust-gas temperature to churn out a faster build up of torque, even at low engine speeds.
The spray-guided direct gasoline injection with piezo injectors positioned centrally in each of the four combustion chambers allow for injection pressure levels of up to 2900 psi, and result in low levels of exhaust emissions. Twin-scroll technology also contributes to a lowered fuel consumption, with the GLA45 AMG returning a respectable 23/29/25 city/highway/combined fuel economy.
Channelling all that power to all four wheels -- the 4Matic all wheel-drive system is thankfully standard -- is an AMG Speedshift DCT seven-speed dual clutch automatic transmission, featuring a Race Start launch control function.
The transmission also offers Manual, Sport, and Controlled Efficiency modes, the latter is essentially a green mode. Start/Stop also present in all driving modes, though it can be disabled via a button like in other Mercedes-Benz models.
Another system which prevents the GLA45 AMG from spontaneously reenacting World Rally Championship-style drifts along gravel roads is a three-stage Electronic Stability Control system, which features a torque vectoring system dubbed ESP Curve Dynamic Assist.
This setup applies minute braking interventions on the rear inside wheel, preventing unwanted understeer created by those training to be the next Seb Loeb. Further keeping WRC ambitions in check is an AMG sports suspension with specially tuned spring/damper units, which, along with bigger anti-roll bars and optional firmer springs and damper tuning, keeps body roll to a mininum on twisty roads.
AMG speed-sensitive sports steering with speed-dependent power assist is designed to add agility, while the high-performance brakes with vented and perforated discs keep it all from going too wrong.