Porsche Mission R Previews Electric Cayman
Colin Chapman, the man who founded Lotus Cars, was fixated on reducing the weight of his cars. “Simplify, then add lightness,” he said. “Adding power makes you faster on the straights. Subtracting weight makes you faster everywhere.” Chapman’s philosophy was proven correct when his Lotus 38 won the 1965 Indianapolis 500 with driver Jim Clark at the wheel.
For automobiles, weight is the enemy. The more a car weighs, the more power it needs to start moving from rest and the larger brakes it needs to bring it to a halt. In addition, the further away from the center of the vehicle the weight is, the less happy it is to turn. A dragster may be quick in a straight line, but a poor choice for an autocross. Lastly, the higher the weight of a vehicle is off the ground, the more it tends to lean over in turns.
To an automotive engineer, the ideal vehicle would carry its weight as close to the ground and as near to the center of a car as possible. That is precisely why many automakers have designed mid-engine cars for their more sporting models rather than having the engine hanging way out in the front or rear of the vehicles.
One of the most gorgeous mid-engine cars ever made was the Lamborghini Miura, which had its jewel-like 12-cylinder engine mounted directly behind the seats. (You can see this car driving through the Italian Alps in the original version of the movie The Italian Job.) Fiat tried to build an affordable mid-engine sports car, the short lived X1/9. Toyota followed that up with three versions of the MR2.
In 1996, Porsche introduced the Boxster. Unlike the classic 911, which has the engine mounted at the rear of the car, the engine for the Boxster was installed ahead of the rear wheels, bringing the weight of the drivetrain closer to the center. Later, Porsche introduced the Cayman, a coupe version of the Boxster (and a lovely car it is!)
Both cars have sold well, but the advent of the electric car era presented a serious challenge for the company. Unlike sedans and SUVs, sports cars don’t have a lot of space to install battery packs. When the EV revolution began, there simply was no way to shoehorn a battery pack with enough range to be practical into the Boxster and the Cayman.
Porsche Mission R
Porsche built its reputation on sportscar racing. It has won the LeMans 24 hour endurance race 19 times — more than any other manufacturer in history. It promotes the Carrera Cup, a one-make racing series that uses bespoke 911 cars. But time marches on and things change. “Motorsport is becoming more electric, digital and sustainable,” Oliver Blume, CEO of Porsche, tells Autocar. “We want to take a lead in making motorsport more attractive for future generations.”
Enter the Porsche Misson R, a design concept for a future all-electric racer that could compete in a separate racing series much like the Carrera Cup. Usually, an electric car mounts the battery under the floor, which keeps its weight as low as possible. But in the Mission R, the 80 kWh battery pack is mounted behind the driver in the space where the engine and transmission normally go.
“We wanted a car that was really low in terms of drag, so the silhouette should be as low and flat as possible, which means you want the driver sitting as low as possible in the car,” says Porsche technical chief Michael Steiner. “That means there’s no space for a battery below the driver. It’s one reason why a lot of super-sports cars today have a mid-engined design. With today’s battery cell technology, the heaviest part of an electric car will be the battery, so by putting it where the engine currently is — packaging and center of gravity wise — it’s more or less the same.”
The Mission R is powered by two motors. The one in front is rated at 429 bhp and is used as the primary means of harvesting electrical power during deceleration. A 644 bhp motor powers the rear axle. Together they offer a consistent 603 bhp in standard driving mode, but can raise that to 1073 bhp in qualifying mode. 0-100 km/h happens in less than 2.5 seconds and the top speed of the car is 186 mpg (300 km/h).
Key to making the Mission R feasible for racing is rapid charging. With an 800-volt electrical architecture, it can be charged at rates of up to 350 kW, enabling a 5-80% fill in 15 minutes. The battery has been designed to last for 35-40 minutes, which is about the length of a current Carrera Cup race. This is a serious electric racer designed to equal the performance of a petrol counterpart, Autocar says.
Electric Cayman
Autocar also says that to make an electric racing series affordable, it needs to be based on a production car. That is likely the reason the Mission R is very close to the dimensions of the current Porsche Boxster and Cayman vehicles. But an electric version will not be a cut-and-paste job using the existing chassis.
“When we electrify a model, we won’t do a carry-over of the combustion engine [platform] because there are too many compromises. When we are looking to future sports cars, we would develop its own platform but connected with some modules coming from other cars. But the platform will be unique,” Oliver Blume tells Autocar.
“There is no platform unchanged by electrification, but the only platform within our portfolio that might not change that much would be for mid-engined cars like the Boxster and Cayman,” says Michael Steiner.
“Ten years ago, we started with prototypes of electrification with this mid-engined layout because you could use the space of the engine and transmission for the battery.
“But we decided within Porsche, starting with the Taycan, that we will do no conversion-type design, with space for an internal combustion engine, plug-in hybrid or fully electric options, because there is always some compromise in weight, package and other dimensions. So even for mid-engined cars, we still see a good reason to just design a full-electric platform. That might change, but not in the next few years.”
Steiner hints that the platform for the Mission R could also be used for high performance cars from Lamborghini and Audi in the future. “This is not only driven by technology,” he says. “Often, the main direction comes from what we expect the market would favor, and then we try to develop the technology in that direction.”
When asked if there is interest from customers for an electric Cayman, Steiner said: “I would say yes, but this needs weight reduction. If you drive and push a real sports car on the race track, you would still feel this [weight]. You might not notice it on the highway, but a real sports car has to perform on the race track.”
Which brings us back to Colin Chapman and his “add lightness” design philosophy. Will Porsche figure out how to make a battery powered Cayman that honors the company’s racing heritage and do it at a price customers can afford? Just a few years ago, the answer would have been no. Now, it’s a definite maybe. Tomorrow…?
Keep in mind that the Porsche Mission E gave us a pretty good idea of what the production Taycan would be like. Chances are the Mission R gives us a good idea what an electric Cayman would be like as well. If you are a Porschephile, that is good news.
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