When Volkswagen went all out for diesel: the XL1 and Lupo 3L

When Herbert Diess took up his new position in July 2015, the story goes, the new Volkswagen brand boss immediately approached his engineers: “Show me your electric models!” They looked around and said, “Well, that’s the Golf VII, which we converted into an electric car. And this is the Up, also with an electric motor and a battery instead of a three-cylinder petrol engine.”

“And the other models?” asked the new Volkswagen boss, who previously led BMW’s development and launched the compact i3 and the sporty i8 in 2013. “What other models?” the Volkswagen employees seem to have asked. They then indicated that they had no further models to show. In retrospect, we know the reason for this: at Volkswagen they went all out for diesel. They wanted to further develop that engine type into a particularly sustainable solution. But then came the emissions scandal and, a little later, Herbert Diess. This accelerated the development of electric cars in Wolfsburg.

Today we put the diesel heroes of yesteryear in the spotlight. Speaking of diesel, we should definitely mention the genius engine developer Dr. Karl-Heinz Neumann. He is responsible for the following innovations (in addition to various 10-, 12-, 16- and 18-cylinder engines): the first environmentally friendly diesel engine with catalytic converter in the Golf II (1989), the first auto-igniter with direct injection (of the group) in the Audi 100 (1990), the first diesel with pump injector technology in the Passat (1998), the first aluminum diesel engine in the Lupo 3L and thus the first series-produced car with an average fuel consumption of three liters per 100 kilometres. That was in 1999. The Lupo, that little piggy bank on wheels, set new standards in terms of consumption.

1 liter of diesel per 100 kilometers

But in Wolfsburg they wanted more. On April 19, 2012, Ferdinand Piëch, then head of the company’s supervisory board, drove the XL1 one-litre car from Wolfsburg to Hamburg for the annual general meeting, with Volkswagen boss Martin Winterkorn behind him in a second prototype. One liter of fuel consumption per 100 km, or 1 in 100! It was the day the diesel turned green. Let’s turn back time and go out with the two ‘greenies’. The white car with the registration number GF, letters referring to the municipality of Gifhorn near Wolfsburg, and KG 404 behind it, appears to have once been parked in Martin Winterkorn’s driveway. Whether the letters KG stood for ‘König Griesgram’, or ‘King groan’, is not known. It is also not known whether the grumpy ‘Wiko’ has ever laughed behind the wheel.

800 cc TDI hybrid

It is certain that this is a masterpiece of engineering. No, we’re not talking about getting in and out; you don’t want to be seen in front of a full terrace. You first have to lift your leg over the thick and very low sill, then somehow squeeze yourself in and then forget that you have to do the whole thing in reverse later. You better marvel at the amazing technology: the two-cylinder engine is half a 1.6 TDI, has a capacity of 800 cc and an output of 48 hp and is placed on the rear axle, with a fast seven-speed DSG bolted to it. This in turn provides space for the hybrid module with an electric motor and the clutch. A lithium-ion battery with 5.5 kWh is mounted at the front, which supplies the electric motor with power via a high-voltage cable and recovers the energy when braking. And then there’s the very consistent lightweight construction: a lot of expensive carbon fiber reinforced plastic is used, the body is made of a mix of the same material and light metal, and the forged magnesium wheels are wrapped with ultra-thin 115 tires. The result of all efforts is a weight of only 795 kilograms. If you firmly step on the accelerator, the two-cylinder engine goes to work. The transition from electric to diesel is so smooth that your head doesn’t make any nodding movements.

Frugal can also be fun

You only do that when you drive through bends on a narrow provincial road, and you do that out of appreciation. The steering wheel requires only 2.5 turns from the far left to the far right. The Volkswagen technicians have tuned the steering in such a way that it is nice and direct. In addition, the chassis has a fine, strong adjustment. You can’t blame this rear-wheel drive for having a rear axle that’s so narrow you can’t see the wheels for aerodynamics. This car makes it clear that being frugal not only saves money, but can also be fun.

Lupo 3L 150 kilos lighter than normal Lupo

We can already reveal that the driving pleasure in the Lupo does not even come close to this. But we have to judge this car by the role it had to play at the time. Let’s take a look at its achievements, such as the large amount of aluminum and expensive magnesium used for the chassis and body. We see and feel that on the three-spoke steering wheel in front of us. The seat frames are made of light metal and the aluminum wheels are forged especially for the Lupo 3L. Due to all these measures, approximately 150 kilos of weight have been saved compared to the basic Lupo. A curb weight of 865 kilograms is close to that of the Golf I, which had no airbags and no ABS on board, but also no power steering, like the Lupo 3L. With this dwarf of 3.53 meters, everything was done to optimize the aerodynamics. For example, the air openings at the front have been reduced, the sills have been extended further down and thin tires with low rolling resistance have been fitted. And of course the engineers did something to the engine.

The three-cylinder unit injector TDI is mated to an automated five-speed gearbox with coasting function; so there is a bit of Smart in this Volkswagen. You notice it when accelerating: 21, 22, a nodding head, gear set. Even the windows of the Lupo caught the attention of the engineers. The side windows are thinner, which saves weight, but you do hear the diesel doing its job loudly. It almost seems to have been done to remind you not to accelerate too much, after all, consumption must remain low.

1 in 25 and 1 in 50 in practice

Ultimately, the question of consumption is also a question of character. Because we don’t want another diesel scandal, we’re telling the truth. A consumption on the right side of 1 in 30 has succeeded us in the Lupo just as little as a consumption of 1 in 100 in the XL1. After all, we drove through everyday practice, not on the test bench. But a consumption of about 1 in 25 in a 24-year-old Lupo 3L and almost 1 in 50 in the very limited edition XL1 are really okay! So after our test drive we fill the ten-liter tank of the XL1, which fits 3.6 liters of diesel. We wonder what would have happened if Volkswagen had continued its research into diesel engines. What if politicians only set the goal and the engineers then figure out the way? After all, they have studied for it. Maybe the diesel engine would be really green now.