Skip advert
Advertisement

Mercedes-AMG A45 S review - engine, gearbox and technical specs

AMG has extracted more power from the A45’s 2-litre than any other currently in production

Evo rating
  • Huge performance, engaging chassis, interior design
  • Expensive, A35 delivers a similar experience for less

Far from being just the A35’s 2-litre turbocharged engine with an ECU tickle, the A45’s power unit is effectively all-new. The whole thing is rotated by 180 degrees compared to that of the A35 (so it’s still transversely mounted) with the exhaust ports and turbocharger now on the firewall side and the intake at the front, to the benefit of airflow and cooling.

Advertisement - Article continues below

The turbocharger is different too, with roller bearings for reduced friction, and divided ducts to separate exhaust pulses for faster, less disturbed flow. Lessons learned from AMG’s hot-V V8s mean the turbocharger is cooled by oil, water and air, the latter by special ducts in the engine cover, while the wastegate is electronically controlled.

In the engine itself there are different valves, two-stage fuel injection, separate water pumps for the block and cylinder head, a two-stage intercooler, and a baffled sump to prevent oil surge under high cornering loads. Oh, and the whole thing is put together like a proper AMG engine – handbuilt by one individual in Affalterbach.

So what does all this get you? The answer is 415bhp at 6750rpm and 369lb ft of torque from 5000 to 5250rpm. Don’t let the narrow torque band fool you either – this engine is mighty throughout its rev range, no less than you’d expect for the most powerful 2-litre engine in production, and the most powerful in any hot hatch. While we’ve seen engines at this level before, most notably in Mitsubishi Lancer Evolutions, bear in mind too that this won’t require anything like the sub-3000-mile oil changes required of that car…

Power is sent to all four wheels, first through an eight-speed dual-clutch transmission (rather than the A35’s seven-speed DCT), then through, at the rear axle, a pair of multi-disc clutches to direct power to whichever wheel needs it most. All this tech comes at a cost though, and it’s not just the purchase price – the A45 S weighs in at 1560kg, or around 80kg more than the AMG A35

Skip advert
Advertisement
Skip advert
Advertisement

Most Popular

Alfa Romeo 4C – the car world's greatest misses
Alfa Romeo 4C
Features

Alfa Romeo 4C – the car world's greatest misses

It had stunning looks and promising hardware, but somehow the 4C didn’t add up to the sum of its parts
20 Jun 2024
Cupra Leon Estate VZ3 2024 review – Cupra’s rival to the Mercedes-AMG CLA35 Shooting Brake
Cupra Leon Estate VZ3
Reviews

Cupra Leon Estate VZ3 2024 review – Cupra’s rival to the Mercedes-AMG CLA35 Shooting Brake

The Cupra Leon has been updated to match its Golf GTI and Audi S3 cousins, bringing more power, a refreshed design and a welcome dynamic edge to the h…
23 Jun 2024
Bugatti Tourbillon revealed – the 1775bhp, V16-engined Chiron successor is here
Bugatti Tourbillon – front
News

Bugatti Tourbillon revealed – the 1775bhp, V16-engined Chiron successor is here

With a naturally aspirated V16, a new carbon chassis and a 273mph top speed Bugatti’s latest hypercar has the GMA T.50 in its sights
20 Jun 2024