The 550-horsepower hot hatch you've been waiting for is here.

Remember when Mitsubishi squeezed 440 horsepower from a turbocharged four-cylinder 2.0-liter engine? It happened about four years ago when the limited-run Lancer Evolution X FQ-440 MR came out in the United Kingdom with 440 horsepower and 412 pound-feet (558 Newton-meters) of torque. Fast forward to present day, that special edition is starting to pale in comparison to Posaidon’s little monster based on the outgoing Mercedes-AMG A45.

Update:

The German tuner fiddled with the compact car’s 2.0-liter engine born in Affalterbach and managed to extract a whopping 169 hp for a grand total of 550 hp. The torque generated by the four-cylinder mill was also boosted from the series 475 Nm (350 lb-ft) to no less than 660 Nm (487 lb-ft) channeled to the 4Matic all-wheel-drive system. Fun fact: the torque is actually electronically limited to preserve durability of the internals.

How were they able to increase output by such a significant margin? AMG’s M133 received an upgraded turbocharger, bigger charge air cooling, motorsport-derived spark plugs, revised air intake, and a completely new exhaust system made from stainless steel and equipped with an electrically controlled valve. The four-cylinder also features a water-methanol injection system and a re-mapped ECU tailored to the modified hardware.

Naturally, Posaidon also had to tweak the seven-speed, dual-clutch transmission to make sure it would cope with all the extra muscle. The good news is the tuner mentions it will further modify the AMG DCT in order to make it handle even more torque, because 660 Nm in a compact hot hatch is obviously not enough.

Mercedes-AMG has promised to give the next-generation A45 more power, but don’t expect anything remotely close to this tuner project possessed by the horsepower demon. The new A45 likely due to arrive next year will have over 400 hp, with a rumored hybrid version to be launched further down the line with a higher output. Meanwhile, a warm A35 will be out in the second half of the year with over 300 horses.

Source: Posaidon

Mercedes-AMG A45 by Posaidon