They keep saying it, but is anybody listening? Seat (whose model line-up comprises four monoboxes and a supermini, remember), is a sporty brand. And this year, it’ll take ‘another step forward as a sporty brand’, through ramping up its assault on the World Touring Car Championship and by launching sporty cars like this: the Altea FR.You see, the Altea FR is, we are assured, a sporty monobox. Now, should be partial to office boredom-relievers like meeting bingo and find yourself in a conference with Seat executives, bear in mind that ‘Sporty’, ‘Diesel’ and ‘Monobox’ are the three absolute bankers, regardless of how unlikely you are to ever hear them phrased together outside of Martorell.Still, say you do believe it. Or that you don’t, but are, understandably enough, intrigued by this new, 170PS (168bhp in our parlance) performance diesel engine in an £18,000ish Altea. What, exactly, does it offer?Most obviously, a set of large alloy wheels plus, of course, the trappings of performance-oriented family models the world over: silver door mirrors, larger bumpers, twin-exit tailpipe and TDI badging with all three letters hued red. Inside, excellently bolstered front-seats, sculpted steering wheel, splashes of, well, carbon-effect-effect trim and white-faced dials.The new engine is based on the 138bhp turbodiesel that already accounts for a quarter of Altea sales, but benefits from revised turbocharger geometry, a new intake system, particulate filter and, most notably, piezo-electric fuel injection, which helps with the powerband.Take sixth gear acceleration from one of the toll stations on our test route, for example: initial uptake, 1000-1500rpm, is sluggish, but then it’s - properly - into its stride, 500rpm sooner than we’ve become used to. If we’d tried the same with the 138bhp engine, we’d still be there now, waiting for the trademark whoosh at 2000rpm.There’s no disadvantage at the higher end, either. Peak power arrives at 4200rpm and, during the preceding 1000rpm, you’ll notice the engine doing its best work. Pin pedal to carpet and it revs reasonably freely all the way to 5000, though there is no particular benefit from exceeding the low fours.And shhh, I think it’s quieter, too. In fact, I’m certain it is under load below 3000rpm. When idling or revving its merry head off, it would still be shamed by any given petrol unit, but at a cruise, it remains, as is typical nowadays, imperceptible.So, an engine with an output and nature, if not aural quality, fit for a sporty car. What of the chassis? Ride is par for the course: occasionally over-harsh, but acceptable on good roads. There are thicker anti-roll bars at both ends, too. At the rear, this makes it stiffer, but the front one is actually 20 percent floppier because it is now hollow rather than solid. The aim? To make this Altea more agile.And so it does. The Altea’s inclination to turn into corners is much improved. Roll is contained, the front grips willingly and the rear responds faithfully. Tendency to understeer is still present and correct, but lift and the rear will, under some circumstances, obligingly relinquish its hold. The (switchable) stability programme allows a little slip at either end, while the FR also comes with fancy electro-trickery that, should the car slide excessively, assists turning of the steering – effectively prompting the driver for a dose of corrective lock.Sadly, the steering’s information feed is entirely absent at other times. Smooth, yes; responsive, true; and the wheel itself has some tactile quality. But its output has been muffled, and blame lies at the door of that excellent engine’s torque: all 258 traction-breaking lb ft of it that’s available from 1800rpm. Exit a second- (or slippy third-) gear corner with a tactless right foot and the front wheels will attempt their escape. Rather than alert the pilot to this all-too frequent indiscretion, the steering’s eye is turned blind, leaving reigning-in activity to the (perfectly adequate) traction control.And it’s details like this that prevent the Altea FR from being the sporty car that Seat would like us to believe. Yes, it’s fast. But what of involvement, sound or tactility? This is where genuinely sporty cars make a case for themselves. And where, regardless of the claims, we regret that the Altea FR cannot.