With the 2.5-litre five-cylinder turbocharged petrol engine installed, the Ford Mondeo has the means to make the most of its polished driving dynamics. The car's core fleet market may baulk at running costs some way in excess of the diesel alternatives but the oil-burners don't bring a grin to the chops like a 2.5T.

An engine that makes a small car fast often only succeeds in making a larger car thirsty. Recent automotive history turns up numerous examples of powerplants lifted from rip-snorting hatchbacks and optimistically fitted to a bigger vehicle only for the laws of physics to lower a big dampener onto proceedings. This factor initially encouraged a degree of scepticism where Ford's Mondeo 2.5T was concerned. The car's engine first rose to prominence in the flying Focus ST but how would it fare powering less hardcore models in the mid to upper echelons of the Mondeo range? We've been running one on our longterm fleet to find out.

A unit that feels unstoppable in a small, lightweight vehicle can easily be rendered distinctly average when it's burdened with extra weight to lug around. That averageness is then compounded by the spectre of increased fuel consumption and emissions. Running costs are always going to be a thorny issue for a 220bhp turbocharged petrol engine in the fleet-dominated medium range sector, so the Mondeo's big hitter needs to deliver some real sparkle in order to avoid being passed over in favour of prosaic diesel alternatives.

The 2.5T engine produces 217bhp and can punch the hefty Mondeo through the 0-60mph sprint in 7.3 seconds. That's sufficiently rapid to retain the interest of all but the most power-crazed photocopier salesman. Top speed is 152mph but the most telling figures where this engine is concerned relate to its torque output. We're used to making torque-based comparisons between petrol and diesel engines that highlight the relative limp wrists of the petrol unit. The 2.5T, however, produces its 320Nm maximum between 1,500 and 4,800rpm while the Mondeo's 2.0-litre 138bhp TDCi diesel develops its identical 320Nm top whack between 1,750 and 2,240rpm. The petrol's wider torque spread actually gives it greater flexibility and that goes in the plus column alongside its superior refinement and sporty character.

"If saving cash is your top priority, you'd best avoid any sort of contact with the 2.5T - it could easily suck you in."

Like the best turbo engines, the 2.5T doesn't feel as though it's relying on forced induction to achieve its performance. Acceleration eases on smoothly almost from the first prod of the throttle, reaching its zenith at 5,000rpm where maximum power is produced. Persevere at this point and a distinctive burbling exhaust note will spur you on to the red line. The diesel-style muscle low down in the rev-range makes the 2.5T Mondeo a relaxed everyday companion but the engine still rewards when extended, inviting you to enjoy the Mondeo's fluid ride and taught chassis. Quite simply, if you're looking for an involving drive, the Mondeo trumps everything else in the medium range sector and even gives the compact executive elite cause for concern.

Ford obviously had BMW and Mercedes products in its sights when creating the Mondeo. Some of the essential sharpness of the previous generation car was sacrificed this time around in favour of superior refinement and quality. The independent multi-link rear suspension works with the MacPherson strut set-up at the front to achieve a litheness and composure over poor surfaces. Anti-roll bars fore and aft help the Mondeo corner flat and the sound insulation reduces wind-noise to a murmur at high speeds. The 2.5T engine is barely audible at idle and only minor vibrations find there way inside.

Take a seat at the wheel and you'll notice high quality materials and finishes. As with the outside, dynamic lines and styling curves are evident, plus the low profile instrument panel provides very generous cabin space for front seat occupants. The dashboard is clear and the major controls for the electronics systems largely intuitive, although there was rather a lot of brushed aluminium in our Titanium X test vehicle and the wood veneer finishes fitted to the Ghia models will have anybody under the age of 50 recoiling in horror.

The Mondeo is a seriously big car with generous room for five occupants and a boot of epic proportions. It's big on the outside too of course, but the expertly-judged driving experience masks the cars substantial dimensions when you're on the move. The high window line and steeply raked rear mean parking is less straightforward than in frumpier rivals.

The 2.5T engine is available in the up-spec Ghia, Titanium and Titanium X trim levels at prices that kick off at £20,945. The saloon and 5-door hatch bodystyles are priced identically but the estate carries a £1,250 premium model for model. It mean that the ultimate 2.5T Mondeo is the Titanium X estate at £24,195. At this rarefied end of the Mondeo line-up, equipment levels are of course generous. Even the Ghia features a 6 CD Sony branded stereo, powered mirrors, automatic headlamps and wipers, 17" alloy wheels and ambient interior lighting. By the time you've ascended to the Titanium X, you're positively swamped by desirable titbits. It's only at this level that you get the engine starter button that's dramatically labelled 'POWER'.

Ford has made a conscious effort to nudge the Mondeo upmarket. The traditional medium range sector has been squeezed of late by the glut of equivalently-priced compact 4x4s and premium hatchbacks and no longer has the cash cow potential it once did. By endowing the Mondeo with extra desirability, the thinking is that base models will still mop up medium range sales while the higher spec derivatives like the 2.5T range may pinch less badge-conscious buyers from the arms of the prestige brands.

Company car drivers tend towards diesel engines in order to avoid the crushing sensation that they've financially shot themselves in the foot, the feeling plaguing them on their daily slog to and from work.

It's true that a diesel Mondeo represents a more affordable choice but if saving cash is your top priority, you'd best avoid any sort of contact with the 2.5T - it could easily suck you in. Fuel economy is officially measured at just over 30mpg and Ford claim that you can expect 40mpg on a motorway run but we found both marks difficult to achieve - possibly because the car nags you to let it off the leash at any and every opportunity. CO2 emissions of 222g/km will also be problematic for company car market and that more than anything will restrict its appeal in fleet circles.

By way of comparison, the Mondeo's 140bhp TDCi diesel officially returns almost 48mpg and emits 156g/km of CO2, making it a notably more cost-effective proposition as a company motor.

The benefits of the 2.5T engine may be lost on traditional Mondeo buyers who choose the car as a tool of their motorway pounding trade. The associated economy and emissions don't stand up well to on-paper comparisons against the alternative diesel engines. If you can put the taxman's machinations to the back of your mind, however, you've got to love the 2.5T Mondeo. The engine's mix of diesel-esque torque output and petrol engine refinement make it an unbridled pleasure on longer trips but that sporty character always bubbles under the surface. Fierce performance evokes the unit's Focus ST origins and a snarling engine note invites you to use the excellent Mondeo chassis as its designers intended. The head will always plump for diesel but when the heart cries out for a 2.5T, it's well worth a listen.

Overall, the Ford Mondeo makes a commendable attempt at surpassing established medium range levels of design, build, surprise and delight. It certainly feels special inside with an aura of quality about the cabin even if some of the trim finishes do try a little too hard in the up-spec models where the 2.5T engine is available. Outside, the Mondeo looks great with its coupe-like profile and distinctive front end and on the road, the sporty character of the driving experience really comes through. If you bought this car with a premium badge on its nose, you really wouldn't be disappointed.