This week I have been reading mostly about the battle of the north Atlantic, and just how terrifying and terrible life must have been for Britain’s merchant seamen.

The seasickness, the bone-numbing cold, smoking with cupped hands so Fritz couldn’t see the glow through his periscope, and then, when (not if) you were torpedoed, being plunged into the oggin where your head was cooked by the burning fuel oil and your body frozen by the icy waters. Sausages suffer a better fate on the barbecue.

But they had to keep going out there because Britain needed 55m tons of imported commodities each year to survive and, by 1941, thanks entirely to the U-boats, the amount coming in had been nearly halved. We barely had sufficient raw materials to build ships to replace the ones being lost.

Consider the maths. The U-boats were sinking more than a hundred ships every month. In 1942 alone 7.75m tons of Britain’s merchant fleet went to the bottom. To make matters worse, for every seven ships sunk the Royal Navy was getting one U-boat. So you might deduce from all this that we were getting our stiff upper lips kicked in.

But no. Churchill once said that he considered U-boats to be the biggest threat to our survival and as a result a huge amount of time, money and manpower was diverted to thinking of ways they might be neutered.

This set in motion perhaps the most astonishing techno-race in human history. We developed sonar, the Germans had to think of a way to get round it, we fitted aircraft with radar, the Germans gave the subs radar detectors so they could dive when a plane was on its way. We broke their codes. They broke ours. We built fast frigates. They built faster U-boats. We invented forward-firing depth charges, the Germans built better pressure hulls to go deep, and when we introduced four-engined Liberator bombers that could cover the whole Atlantic, the Germans developed engines that ran on hydrogen peroxide and breathed through snorkels so they never needed to surface. And all of this happened in just four years.

Now, whenever a scientist or an engineer says something might be possible it’s always claimed that no working model will be ready for 30 years. What good’s that, if it’s a cure for cancer? Back then they were having ideas, testing them, building prototypes and getting the damn thing into production in weeks.

Of course, war is a great motivator. A point that’s being made obvious by the horsepower race we’re seeing at the moment.

Since the Germans aren’t allowed to fight other countries any more, they’ve decided to fight themselves with Audi, Volkswagen, Mercedes and BMW all engaged in a full-on scrap to see who can extract the most power from a road-going engine.

It all started I suppose when BMW announced the M5 would have 400bhp. That seemed like a colossal achievement and I remember remarking at the time that Jackie Stewart had had less when he won the world championship. But pretty soon Bee Em’s 400bhp V8 was made to look like a paraffin stove.

Mercedes came along with a supercharged 5.5 litre that got perilously close to 500. Then Volkswagen announced it was working on a Bugatti supercar that would offer drivers a nice round 1,000. And to show they were serious, they built a twin turbo W12 for the Bentley Continental with 552bhp.

BMW immediately scuttled back to its drawing board and began work on a V10 for the next M5, while Mercedes pointed the eeking machine at its 6 litre V12. This was deemed a “bit light on the throttle”, so they enlarged it to 6.5 litres and added a couple of turbos. The result was 612bhp. A few supercars claimed marginally more, but when it came to torque this engine was way out in front with 738 lb ft. In short, it was the most powerful road-going engine ever made . . . and now they’ve gone and put it in a car.

Putting 738 lb ft of torque on the road is like putting a full-scale avalanche in a snow shaker. It’s like lighting your sitting-room fire with Mount Etna: 738 lb ft of torque is insane.

Maybe, just maybe, and this is an argument that hangs by a silvery thread, Ferrari could get away with such a move. The car would need to be carefully designed by people who understood aerodynamics and traction and it would almost certainly not resemble any car we’ve ever seen. Who knows, to contain and harness that much power it may have to look like a Saturn 5 launcher, or an oil rig. Or a pepper grinder.

But no. Mercedes has simply slotted its amazing new power plant into the ordinary CL. Oh, they say they’ve beefed up the drive shafts and fitted bigger brakes, but that’s like saying, “Yes, we’ve employed Satan to teach Form IVb this year but it’s okay because we’ve confiscated his cape”. You can’t put 738 lb ft of torque in a standard coupé . . . or can you?

I knew it was an ordinary Mercedes straight away because even though it had been carefully prepared as a press demonstrator, it arrived at my house with one headlamp not working and a driver’s seat backrest that wouldn’t lock. Standard Mercedes build quality then.

But there was nothing standard about its simply astonishing acceleration. My wife drove it first. Normally she will avoid anything big, heavy or with suspension but her Lotus was away being fitted with more power so she climbed into the Mercedes thinking it was just another hateful squidgemobile. She came home later that day and could only squeak.

I now know why. It is hysterically fast. From 60 to 130 it goes like a rocket, but, unlike any similarly speedy supercar, it makes no noise in the process. At 150 it sounds like a gentle breeze.

And better still it’s comfortable too. Amazingly, Merc’s engineers have not felt the need to fit suspension made from brass and oak to try to keep the body in check. So you just glide from place to place, in sepulchral silence, at mach 4. It’s almost eerie.

They haven’t fiddled with the exterior styling either, which means other road users have absolutely no clue about the nuke under the bonnet. I know you’re too grown up to be interested in this sort of thing, but on one trip a bloke in a Porsche Boxster came up behind and flashed his lights, trying to get past.

By the time his girlfriend looked up to see what was in the way, I was already at home reading the children a bedtime story. I would dearly love to have seen his face. “No, really darling, there was a car there — I promise — and then it disappeared.”

You could have an extramarital affair with a car like this, popping out for hanky panky and popping back before anyone knew you’d gone.

Of course there are some drawbacks to all this grunt, like you need to remember that half an inch of throttle movement in an ordinary car increases the torque reaching the wheels by no more than 10 lb ft. Half an inch of movement in the Merc’s throttle and you’ve added probably 200 lb feet. This has an effect on grip.

No, really, any brutality — no matter how minor — will light up the rear tyres, which are not made from kryptonite or dilithium crystals. They’re just rubber, and rubber has a finite level of traction.

If you’re exuberant, you’re going to go off the road backwards. But what a way to go. Germany is still after world domination, but being killed by its attempts this time around might actually be called fun.

VITAL STATISTICS

Model: Mercedes-Benz CL65 AMG
Engine type: V12, 5980cc
Power/torque: 612bhp @ 4800rpm 738 lb ft @ 2000rpm
Transmission: Five-speed automatic, rear-wheel drive
Suspension: (front) Four-link, air springs, anti-roll bar (rear) multilink rear axle, air springs, anti-roll bar
Tyres: Front: 245/40 ZR19. Rear: 275/35 ZR19
Fuel/CO2: 19mpg (combined) 357g/km
Acceleration: 0-62mph: 4.4sec
Top speed: 155mph (electronically limited)
Price: £125,000 approx
Verdict: A three-star car with a five-star punch

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