Remember the Audi quattro? Of course you do. Launched 27 years ago it became one of the most significant cars of the 1980s.

This roomy, civilised, outstandingly quick and entertaining machine was the car that took four-wheel drive out of the fields and proved to a broadly sceptical world that it could turn a good sporting car into a really terrific one. And Audi has used its quattro technology ever since, not simply as a device to power all four wheels, but as a brand-building tool of rare potency.

But while Audi has had no trouble at all updating, refining and redefining the quattro system, the quattro itself has proved to be more difficult to replace — in fact nigh-on impossible.

Since the original died at the end of the 1980s, Audi has produced many fast and capable coupés, but none has come close to capturing the hearts of serious drivers like the first did. However, now it has made another, and on paper at least it seems to stand every chance of recapturing the spirit of the car that created the whole quattro phenomenon.

It’s called the S5 and it is the current flagship of the new A5 range of smart-looking coupés, due on sale in the UK in July. Like the old quattro it is a four-seat coupé with rear seats that can accommodate children and small adults in reasonable comfort, and quite unlike the TT coupé, whose rear quarters are frankly unfit for human habitation.

But unlike the quattro, whose 2.1 litre five-cylinder engine could muster only 200bhp, this one has a V8 motor of twice the size, with 354bhp up its sleeve, easily trouncing the 302bhp of its closest rival, the BMW 335i coupé. And at £39,825 it seems reasonably priced too.

It impresses at once. It feels solid and spacious, while the cabin is up to the usual exemplary Audi standards of good taste and ergonomic efficiency.

The big V8 fires with a purposeful roar and then settles down to an invigorating rumble that promises much for the road ahead. And it really does deliver. All that power makes highly inadvisable numbers appear on the speedo with startling rapidity, while the exquisite thunder of the engine, allied to a quick and slick gearbox, means you need a positively saintly disposition — something I sadly lack — if you’re not to fall victim to its illicit charms.

If all roads were straight and smooth, you’d be looking at the new best car in the class. Unfortunately they’re not, so you aren’t. It used to be with a sense of weary inevitability that I would discover yet another sporting Audi that failed in the corners to match standards set on the straights, but I really did think this one would be different.

This is the third new Audi coupé I’ve driven this year, and the first two were a revelation: the new TT was a big improvement over the old and the R8 was an astonishing first-attempt bullseye at building a car that not only went as a supercar should but handled like one too. Sadly, however, it seems Audi’s priorities were elsewhere when it went to work on the S5. Despite using a new platform that will also be used for the next generation of A4 saloon, all those familiar feelings came flooding back to me as I headed for the hills. It just didn’t like the twisty stuff.

There is something wrong with its ride, too. You don’t need a mountain road to know a car’s suspension is too stiff — a small pothole, ridge or lump will do the job nicely, and here in northern Italy, as in the UK, these are in abundant supply.

At first I hoped this reflected nothing more than an extremely sporting approach taken by Audi. No such luck: it’s an intrinsic problem and a distraction. Like all Audis, the S5 covers the ground quickly and with very little drama, but I want more from such a car than an objectively impressive display of competence. I want a car like this to make me part of the action rather than simply directing it. Instead it feels aloof, carrying out your instructions simply because it has to rather than because that is what it was created for.

There are, of course, many who will buy this Audi for its good looks and impressive performance, and I would not say they’d be making the wrong choice. It is doubtless a car that will prove better to own year after year than to drive for a single day; it will retain its value very well and will make you look interesting in front of your friends, particularly when you let them experience the full potency of that fabulous V8.

To the traditional constituency of Audi fashionistas I imagine it will prove to be a very appealing product.

But what I cannot see it doing is persuading those to whom driving pleasure matters very much to forsake their BMWs for it. A 335i coupé is perhaps a little slower, but only a fool presumes that speed and fun are always the same.

Ultimately, it is a car for the Aled Joneses of this world. In a recent documentary he learnt to play the drums and then opted to play his big live gig, not with some hard-hitting gods of rock, but instead with Chris de Burgh.

I’m not saying that was either right or wrong. It’s just not me.

Vital statistics

Model Audi S5
Engine type 4163cc, eight cylinders
Power/Torque 354bhp @ 7000rpm / 324 lb ft @ 3500rpm
Transmission Six-speed automatic
Fuel/CO2 22.7mpg / 298g/km
Performance 0-62mph: 5.1sec / Top speed: 155mph (limited)
Price £39,825
Verdict Further proof that fast and fun are not the same
Rating 3/5
Date of release July

The opposition

Model BMW 335i M Sport Coupé £35,760
For Engine, ride and handling balance, price
Against Bland looks, iDrive operating system

Model Mercedes CLK 500 Avant Garde £47,675
For New V8 engine gives colossal performance
Against Very expensive, design getting old

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