Tesla Model S P85D, Mercedes CLS 63 AMG S 4Matic, Front view 31 Photos Zoom

Tesla Model S vs. Mercedes CLS 63 AMG S: 690 electronic HP take on 577 V8 HP

To buzz or roar, that is the question. Can Tesla's electric superstar, the Model S P85D, keep up with the acceleration pressure of a Mercedes CLS 63 AMG S? An all-wheel comparison with a great deal of power, in perfectly dreadful weather.

All I can see is rain and snow on the lens." The otherwise most jovial of all photographers competes with the weather over who is in the grumpier mood. And the editor has little empathy: "Fantastic, so little grip with so much power. This is exactly what an all-wheel comparison needs." Sometimes the beauty of the image must be sacrificed at the expense of the task at hand.

The Tesla Model S, an icon of the drive system revolution, has been given an all-wheel drive system. A fact that only evokes yawns within the old world of combustion engines – in the case of the Model S, on the other hand, Internet and Youtube euphoria as has barely been seen in any other car before. More than 26,000 videos with various dragster races and passengers chortling with joy can now be found by searching for the model designation of the Tesla P85D. Here D stands for Dual Drive and two electric motors: a familiar one at the rear axle with 469 HP and a new one at the front axle with 221. Mechanically self-sufficient and – expressed in the most beautiful engineering jargon – coupled via the road. In total this makes 690 HP (515 kW).

Tesla's Model S P85D does not purchase power at the expense of efficiency

While German electro-mobility technicians are still speculating intensively as to how much of the power and range stated in the drive statistics everyday drivers will need for their electric car, the boys at Tesla casually let fly shots from the extremely large electron gun. Knowing full well that nothing sells a car better than emotions, including, and perhaps especially in the case of electric cars. And with the knowledge that with electric engines an increase in power does not necessarily mean reduced efficiency.

The Californian electro-freaks around their superstar, Elon Musk, play with emotions like surfers in Malibu play with the waves: the Dual Drive only activates its full power after pressing on an 'Insane' button. Imagine if a Mercedes or VW engineer were to issue such a proposal. Exactly: completely barmy. Because in an electric care it is not the engine, but rather the battery – here comprised of 7,000 industry standard "18,650" rod cells – that determines the power, it can now finally develop its true power potential. Power, transmitted via a little electromagnetism, 930 Nm.

577 HP in the Mercedes CLS 63 AMG S

Average: alongside the Tesla Model S a Mercedes CLS 63 AMG S crouches on its springs which only draws its current potential from a 12.8-volt lead battery. Beneath its bonnet beats the softly bubbling resting pulse of a 5.5-litre biturbos with 577 HP (430 kW). Normally we do not write the kW value in brackets afterwards, but to only talk of horse power in a comparison with an electric car really isn't appropriate.

The factory specifications for both all-wheelers for the acceleration to 100 km/h are pretty close together: 3.6 seconds for the lighter AMG and 3.4 for the stronger Tesla. May the car with the better traction win. The old world vs. the new. Current vs. flames. Without a sound the Insane switch in the Tesla Model S slips into its On position. The driver's foot nails the power pedal to the floor and the Californian D-model springs forwards like the a cracking whip. No noticeable delay, the pressure is seamless, slip-free and threshes its head backwards like a bad-tempered pro wrestler. The driver struggles for air: what sort of electric hell is this? The rear of the car doesn't even move as the Californian volt catapult attacks the old combustion-based establishment with giga-pressure.

The V8 roars as it sets of in pursuit of the electric car.

Meanwhile in the CLS AMG: the drive mode switch clicks to the RS position, that is Race Start mode. Left foot securely on the brake, a pull of the gear shift paddle confirms the mode, the rev count levels off at just under 4,000 rpm, release the brake and give it full throttle. What follows is a brief moment of reflection – a moment in which the valves, cylinders, gears and clutch agree on the traction conditions. This lasts for just a split second, but by this time the Tesla Model S has long left the starting blocks. With a furious roar the AMG sets about hunting it down. Adopting the quickest mechanical path, its partially electronic locking differentials struggle for traction and the next gear is automatically engaged in just one tenth of a second.

But it is not enough. The Tesla doesn't have to deal with any transmission/clutch/fuss. It adjusts the precisely dosable power at the grip 100 times per second. The drive silence is overwhelming. Regardless of how the AMG performs on the wet track, the Tesla Model S is cooler and faster. Regardless of how many frighteningly fast short bursts of speed you make. There is hardly a worthy competitor out there. At least not one that still offers up to seven seats. In this case such euphoria is certainly appropriate – not just on Youtube.

Tesla Model S - full power is a brief pleasure

But just not on a sustained basis. At full load, an electric engine such as this slows down much quicker than a combustion engine and drains the scarce energy quicker. On account of this, the nine minutes for which the battery, measuring 85 kWh gross and 75.9 kWh net, would deliver power at full throttle is a purely theoretical value. 515 kW have for a long time no longer been required in order to remain at the limiting speed of 250 km/h. With a relaxed accelerator foot, the P85D owner can casually cruise along for over 300 km. In this respect the loss of range compared to the lighter Model S rear-wheel-drive version is minimal. Firstly because with an electric car weighing over two tonnes, a hundred kilos here or there is not crucial, also on account of the recuperation. And because the new, also asynchronous front engine is more efficient than the old one. OK, efficiency wasn't the be-all-and-end-all here either, at least not in accordance with very elitist electric engine measures.

The AMG takes just five minutes to be fuelled, whereas for the Tesla Model S you have to plan in three quarters of an hour. The network of necessary superchargers, still under development, also still requires a little planning – which incidentally offers free charging. Those who wish to be out in front in the new automotive world still have to make a few compromises. However, the speed at which the Tesla is developing is phenomenal. Thus far the Model S had been lacking assistance systems such as adaptive cruise control or lane-keeping, and now this is available for all models. A pending update is even expected to introduce automatic overtaking. The chassis had also required attention. Not bad for a first attempt, but the precision and agility still left room for improvement. In the Model S with the added D in the name, you now take corners in a much more confident and controlled manner thanks to the adjusted steering, suspension and other stabilisers.

The CLS AMG drifts where the limiter in the Tesla kicks in

But when it comes to handling, the Tesla Model S admit defeat against the snappier and much lighter CLS AMG. In particular, the AMG slides casually into broad drifts on the wet asphalt, whereas the Tesla remains reined in by the ESP at all times. The D will only let a slight amount of slip when moving off on a loose surface or on snow, by pressing a button. In America all-wheel drive is primarily a safety function, and not a speed function. Thus, the Happy People from the west coast no longer have any fun. Tesla chief Elon Musk tweeted: "Main goal of dual motor was actually insane traction on snow. Insane speed was a side effect." Quite honestly, they have sucCee’ded impressively at both.

Alexander Bloch


Hans-Dieter Seufert


16 August 2015
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