Not like it's surprising, mind.
From the moment the current Ford Focus RS was announced, it seemed almost certain that an even more powerful model would be released at some point. After all, several of the Ford's premium hot hatch rivals have higher horsepower outputs, a factory-supported Mountune kit has already bumped up power to 370 hp and it's common knowledge now that Ford's working on a potentially even more extreme model. However, it's Hennessey Performance that's beaten Ford to producing a 400-hp Focus RS.
As probably expected from a car that's been fettled by Hennessey, the Ford Focus RS has had a few under-the-hood modifications as part of its transformation into a 'Hennessey HPE400 Ford Focus RS'. Truth be told, they're not as extensive or as radical as the ones that go into the mega-horsepower Hennesseys, but ECU upgrades, a new air filter and stainless steel additions to the exhaust system are comprehensive enough to liberate another 50 hp from the RS's 2.3-liter turbo-four engine. Considering it's a fairly modest upgrade, the price is also reasonable: $2,995 will get you all the parts, though Hennessey will charge another two grand if you'd prefer the company to bolt them on and dyno test them for you.
If you'd prefer more oomph from your Hennessey-upgraded Focus RS, then you'll be pleased to know the tuners from Texas are working on an even more substantial power boost for the hot hatchback. According to the company, new intercoolers are being planned, along with more extensive exhaust modifications, better turbochargers and new wheels - with the latter allowing Hennessey to fit stickier rubber to the car, so the RS can actually put all the extra power to the road. Better still, Hennessey is claiming more updates on these Focus RS parts will be "coming soon," so it hopefully won't be long until it's revealed just how much more power can be eked out of the RS's EcoBoost engine.