The Mercedes-AMG A 45 S hyper hatch seems to be a hot favourite among the tuners and the folks from Posaidon now offer the RS 525.

That 525 stands for metric horsepower so they have cranked the little 2.0-litre turbo up to 518 hp (386 kW) which is a substantial increase over the standard 416 hp (310 kW).

This upgrade includes a different turbocharger, revised engine mapping, and software adjustments to the eight-speed dual-clutch transmission.

Posaidon estimates it will complete the 100 km/h sprint in just 3.4 seconds and claims it will go on to a top speed of 201 mph (324 km/h).

If this is not enough for you, the tuner is working on an even more potent “Plus” version. Maybe we will see the power output get closer to the ridiculous 592 hp (442 kW) offering from Renntech.