Mercedes-Benz is in the process of renewing its range of compact cars. Already we've seen new A-Class hatchback and sedan models and eventually there will be a total eight body styles in the range.

The good news is that AMG will continue to tune the cars, this time with two performance tiers: 35 and 45 series.

Both series will rely on an AMG-specific 2.0-liter turbocharged inline-4, but while the 35 series is expected to make around 335 horsepower the 45 series will make “well over” 400 hp.

The information was revealed by AMG boss Tobias Moers during an interview with Autocar published Friday.

AMG's current 45 series, which includes an A45 hatchback as well as the CLA45 sedan and GLA45 crossover SUV, generates 375 hp from a 2.0-liter turbocharged inline-4. But with Audi's RS 3 making 400 hp, it's clear AMG wants to be back in the lead.

Mercedes-Benz belt-driven starter generator (RSG)

Mercedes-Benz belt-driven starter generator (RSG)

So how will AMG do it? Enhancements to the 2.0-liter mill are thought to include new fuel injectors, a new turbocharger and changes to the combustion process.

An output of more than 400 horsepower would mean more than 200 hp per liter, the highest of any production model. The title currently goes to the McLaren Senna which has 197 hp per liter.

For subsequent performance increases, AMG engineers are thought to be dabbling with hybrid technology, specifically the mild-hybrid system Mercedes plans to introduce for its next-generation inline-4 engines. The system features a 48-volt belt-driven starter generator that can aid the engine during high-load situations and recover energy at other times. The tuner is also said to be looking at electric compressors.

Beyond the more potent powerplant, the new AMG compacts will also benefit from changes planned for Mercedes’ own next-generation compacts. The list includes a larger yet lighter structure and more advanced electronic driver aids. All-wheel drive will remain standard.

The first 35 series model should be an A35 debuting later this year. Look for the first 45 series model to arrive in 2019.