Lots of boost means plenty more power.

The previous-gen Mercedes-AMG A45 is already quite potent with later models using a turbocharged 2.0-litre four-cylinder making 376 bhp and 350 pound-feet of torque, but a tuner in Greece manages to push the output to over 600 bhp. The major upgrade that allows for the big boost in output is a giant Garrett turbo and a custom exhaust manifold that gives it an eye-catching position in front of the engine when the bonnet is open.

In addition to showing the tuned A45 on a dyno, the video provides a timelapse look at some of the labour necessary for fitting the bigger turbo. Custom engine control software also helps everything work together.

On the dyno, the A45 makes 545 bhp and 467.76 pound-feet of torque as what the text in the video reports as "medium boost." At the maximum level of tune, the engine is good for over 600 bhp, but the clip doesn't provide a specific figure. 

At the end, the video shows the A45 hitting 186.4 miles per hour. Unfortunately, this appears to happen on a public road. The clip doesn't say whether the run happens with the medium or race boost setting, but the end shows the turbos maximum boost of 35.82 psi (2.47 bar) during this pull.

Such a highly tuned vehicle isn't to everyone's taste, and hot hatch customers wanting something potent straight from the factory can look forward to the new A45 that might debut at the Frankfurt Motor Show in September. It comes standard with a 2.0-litre turbocharged four-cylinder making 383 bhp, but a more potent S model has 416 bhp. Both of them have a sophisticated all-wheel-drive system that includes a tail-happy drift mode.