The Seat Leon ST Cupra 300 4Drive is, despite its time-consuming name, not a slow car. With 296bhp, 380Nm of torque and AWD, the Spaniards have produced a baby Audi S4 Avant rival for considerably less outlay.

Now though, German tuner Siemoneit Racing has decided that the Cupra should actually take on - and perhaps beat - the S4’s bigger brother. 

Its modifications have created the Siemoneit Racing Seat Cupra 300, an small estate car with 514bhp and 620Nm of torque – more than both the Audi RS4 and Mercedes-AMG C63 estate. The latter has a V8, don’t forget.

Extracting over 500bhp from a four-pot engine is an impressive achievement. To get there, Siemoneit has fitted the Cupra with bigger turbos, a high-flow air intake and new intercoolers among plenty of other engine upgrades.

With torque also up to 620Nm, the tuners have swapped in an upgraded clutch, the ceramic brakes from an Audi RS3 and Michelin Sport Pilot Cup 2 tyres to help things run smoothly. Perhaps the most exciting addition though is the valve-controlled ‘RipJaw’ sports exhaust. If the noise is even half as good as the name we’ll all be in for a treat.

The result of all of this fettling is a 0–100kph time of just 3.4 seconds and a limited top speed of 278kph, although Siemoneit claims it can manage 304kph when set free from the electronic shackles. Keep it debadged if you want to cause some serious autobahn embarrassment.

All of these modifications don’t come cheap. If you go for the full power upgrade and the ultra-light ‘Vader’ wheels you’ll be paying over £50,000 (RM263,000) for a Seat when you factor in the cost of the original car. That does still keep it well below that RS4 and C63, though, so the decision comes down to whether you prioritise performance or posing…