The Audi TT has had a pretty undistinguished life so far. I thought, when it was launched, that it was as cute as a newborn lamb but that its steering was as woolly and as vague as a sheep. It turned out to be worse than that. After just a few months it began to emerge that on motorway slip roads the Pretty Titty, as I like to call it, would spin round and slam into the nearest solid object.

That was fixed, but worse was to come, because the redesigned cars, identifiable by their tail spoilers, were bought by young men who care just a little too much about their hair. So while it might not be quite so hellbent on actually killing you, it would murder you socially by making you look like an estate agent.

To try to inject some new life into what’s quite an old car now, Audi recently fitted the 3.2 litre V6, which is a good thing, and two gearboxes, which makes it rather jerky around town.

The idea is that when you select, say, third the second gearbox prepares fourth, making the change almost seamless. Apparently each shift is done in something like 0.001 of a second, saving you 0.03 of a second every time you change gear.

Now you might think that it’s an awful lot of bother, fitting an extra gearbox just to save a thirtieth of a second. But after this week I’m not so sure.

Last Sunday I caught an afternoon flight to America and spent until 1am filming in Detroit. Then I drove west for 100 miles to be ready for a dawn photo shoot.

After that was over I filmed the new Ford GT40 for Top Gear — it’s very, very good — and caught the overnight flight back again.

On Tuesday morning I raced home from Gatwick, wrote 3,000 words, quickly, because there was a school meeting that night, and on Wednesday I needed to write two television scripts before flying to the Isle of Man for three filming days. I could have done with more time, but on Saturday night I needed to be in Berlin ready for a Sunday appointment with the new Porsche Carrera GT.

Next week things get really busy, with two overnight shoots, three columns, two features, two commentary records and trips to Surrey, London and St Tropez.

Never have I needed a fast car more. So of course the Mercedes broke down. The gearbox has decided it wants to be a ball gown or a potato, anything but a bucket of cogs, and naturally the spare parts have to come from Germany. I mean, it’d be far too much to expect Mercedes in Britain to clutter the place up with replacement bits and pieces. It might look ugly in the profit and loss accounts.

That’s why I’ve been in the Audi, and on balance I must say I like the new gearbox(es). To hell with the horrid steering and the cherry-wood chassis and the estate agent Bauhaus styling, every second counts and if I can save one after just 30 gearchanges, good.

It is for this reason that there are currently men in the house fitting some kind of wireless transmitter device that allows me to access our new broadband connection.

Just this morning I needed to know when high water was in the Solomon Islands. Now, in the past, that would have necessitated a trip to the library, in a car with only one gearbox, but then along came the internet and suddenly you could get the answer in 10 seconds.

But now, 10 seconds is an aeon. With broadband I can get the Solomons’ tidal charts in one, leaving me time to download Gerry Rafferty’s new album and have a spot of virtual sex with a young lady in Kiev.

At work I’ll take the stairs rather than use a lift that has no “door close” button. Standing there for three seconds waiting for them to shut automatically will make me late for the next appointment and the one after that until, eventually, I’ll miss the heart attack I have scheduled for 2005.

On the roads I don’t curse speed cameras because of the civil liberty issues. I curse them because they slow me down. Every time a traffic light goes red I want to get out and smash it up. On Monday I glowered at a poor woman whose horsebox had turned over on the M25. “I don’t care about your horse. I’ve had to swerve round you and that’s cost me 3.27 seconds.”

But I reserve my special level of hatred, my mental Defcon 4, for people who drive up the A44 at 40mph. I don’t think we should be allowed to kill people who drive too slowly. It is never right to take a life. But I do think we should be allowed to torture them a bit. Saw their legs off maybe, or shove a powerful air hose up their jacksies. Forty may have been all right in 1870 but it’s simply unacceptable now. If all the world did 40 it wouldn’t work any more.

This week, however, I found a woman coming up the A44 at 30 and I went beyond incandescence into a semi-catatonic state of pure rage. My blood turned to acid and fizzed. My heart was filled with hate. I very nearly followed her home, just so that I could burn it down. But there wasn’t time. And to make matters worse, the Pretty Titty didn’t quite have the oomph to get past. Oh, it had the right gear in a jiffy, but the 3.2 wasn’t enough of a heavyweight to exploit the gaps. God, I wanted my Mercedes. Or better still the new Noble M12 GTO-3R.

This doesn’t accelerate when you press the pedal. It explodes. In the time it takes an Audi to select a gear, or the SL to gird its considerable loins, the lightweight Noble has added 10mph to its speed, your eyeballs are fastened to the back of your skull and your left kidney has come off.

It may only have a 3 litre Mondeo engine but the addition of two turbochargers mean it will accelerate from 0 to 60 in, oh, I don’t know, four seconds. Maybe a bit less. And you’ll reach the end of the road way before it reaches its top speed of 170mph.

Speed, however, is only part of the fruit cocktail. The best thing about the old car, with the old 2.5 litre V6, was its handling. It simply didn’t understand the concept of understeer, gripping like an American in hurricane Isabel and then oh so gently allowing the rear to slide in a glorious bout of power oversteer.

The new one is ever so slightly less good. Because there’s so much more grunt from the extra half a litre it’s hard to get the throttle position just right. And it only takes your big toenail to grow a little and oomph, the rear wheels light up and you wind up going backwards in what feels like the smoking room at Detroit airport.

There’s another problem, too. The new engine, and the addition of a six-speed gearbox, has pushed the price to more than £50,000 and it’s hard to justify that. Yes, it does appear to be well made and you do get leather trim, but there are no luxuries at all, apart from air-conditioning. You even have to wind your own windows down.

Sure, it’s faster than a Carrera 2, and more fun as well, but it’s not a Porsche and you can never quite get it out of your head that it was built from plastic in South Africa and assembled on an industrial estate in Leicestershire.

I sort of don’t mind, though, because it is just so very, very fast. And very, very pretty. And who cares if it doesn’t handle quite as well as the old car. Coming second to that would be like coming second to Tom Jones in a singing competition.

The boss of TVR has referred to the Noble as “the South African three-wheeler” ever since its suspension broke in a recent Autocar test. But that shows he’s worried about it.

And rightly so. TVR has been doing its thing for 10 years and nobody has thought to help themselves to a slice of the cake. Now Noble has come along and taken the icing and the cherry, leaving only the sponge.

In a world obsessed with image, you can’t beat a Porsche. But in a world obsessed with time, a Porsche is a library. A TVR is the internet. And the Noble is broadband.

VITAL STATISTICS

Model: Noble M12 GTO-3R
Engine type: V6, 2968cc twin turbo
Power: 352bhp @ 6200rpm
Torque: 350 lb ft @ 5000rpm
Transmission: Six-speed manual
Suspension: (front and rear) Double unequal-length wishbones, alloy uprights, Bilstein dampers
Tyres: (front) 225/40 ZR18, (rear) 265/35 ZR18
Top speed: 170mph
Acceleration: 0 to 60mph: 3.8sec
Price: £51,500
Verdict: The fastest, most beautiful thing to come out of an industrial estate in Leicestershire

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