Our energetic engineer tested the Shell Eco-marathon Prototype Car in Singapore – really slowly.
Our energetic engineer tested the Shell Eco-marathon Prototype Car in Singapore – really slowly.
AT first, it seemed impossible for me to even crawl into the cockpit, let alone fit into the driver’s seat.
But it was an opportunity not to be missed, so I had to challenge myself and brave the claustrophobia for at least one lap of the makeshift test track at Changi Exhibition Centre (CEC).
The Shell Eco-marathon Prototype Car, as it is called, is a one-off vehicle specially designed and built to the specifications stipulated by the rules of the oil giant’s Eco-marathon, which is an annual international event that challenges engineering students around the world to design, build and drive the most energyefficient car.
Shell’s own version, like the Eco-marathon contenders, runs on three wheels and is clothed in a sleek, highly aerodynamic and extremely lightweight skin made from composite materials. The suspension and chassis components are made from aluminium alloy or carbon composites. A petrol engine drives the rear wheel.
Shell does not state any claimed performance figures for its Ecomarathon machine, except that it will easily exceed 177 kilometres on every litre of fuel.
There are other specifications of this prototype that are pretty interesting. For a start, the engine is a Honda GX160.
But, sorry to disappoint you, this motor does not come from any famous Honda racing motorbike and that “160” is not the motor’s power rating in either kW (kilowatts) or hp (horsepower).
Instead, the three-digit number refers to the displacement of each piston, which is 163 cubic centimetres, and since there is only one piston, the total engine capacity is 163cc!
Before you scoff at this singlecylinder powerplant, I should point out that it’s a hot favourite among the budding automotive engineers who build the EcoMarathon Prototype “racers”.
The Honda motor’s claim to stardom is its unburstable nature in different operating environments. In fact, it is used at construction sites to run waterpumps and mini-generators, in airport equipment to power hydraulic devices, in commercial services for power-jet washing, and much more besides.
The GX160 is also a popular choice with many go-kart makers, because it’s ridiculously cheap and readily available anywhere in the world.
The unit is air-cooled, measures roughly 35cm in length, width and height, and weighs a mere 14kg. With a power output of 4.8bhp at a peaceful 3600rpm and a torque output of 10.3Nm at 2500rpm, accelerating from a standstill to 100km/h wasn’t going to happen.
THERE WOULDN’T BE ANY POWERSLIDES, TIMED TRIALS OR HANDBRAKE TURNS.
There wouldn’t be any chance of powerslides, either, even with all the juice channelled to that skinny 45mm tyre in the rear. And there wasn’t going to be any timed trials or handbrake turns at CEC that sunny afternoon.
Once kitted out in the requisite driving suit which included slim-fit footwear seating, or rather, lying position.
I had to lie on my back – yes, horizontally, with neck turned at a right angle so I would have a chance to see out of this bulletshaped pod. There was very little to see, though, because the windscreen is steeply raked and long, but narrowed by thick “A-pillars” on either side.
Throttle control is on the handlebar, as are the brake levers for the front and rear hydraulically operated callipers on discs.
Not that the brakes mattered power-to-weight ratio is critical.
While I could see where the vehicle was heading, it was near impossible to view the apex of the first curve on the circuit and all the curves that followed.
On every approach into a turn, the constricted visibility meant I had to look out of the quarter-window to keep the car at a reasonable distance from the barrier.
With the handlebar almost resting on my thighs, its range of movement was very restricted, which meant the maximum (hardly something I would call shoes), I was briefed on the controls and how exactly to slide into the vehicle.
With the cockpit cover removed, getting in was less difficult than I expected, but adjusting to the correct sitting position was another story.
There is no steering wheel.
Instead, directional control is by a handlebar, which has its central rod running perilously close to the crotch – mine in this case.
Obviously, the steering angle is severely limited, but the most physically strenuous aspect is the much, since I figured there wasn’t going to be a lot of braking during the flying lap.
Moving off from a standstill was smooth and the overall acceleration was far stronger than the engine specifications suggested. This wasn’t surprising to me, considering the extent to which lightweight design was a major criterion for each and every component.
All the Eco-Marathon cars are purpose-built to maximise travel distance on a mere 250ml of fuel – or less than the contents of a Tiger beer can. Hence, the car’s possible turning radius was necessary at each circuit curve.
But isn’t that what we are supposed to do on a racing track? Minimal steering angle means minimal tyre scrub and, therefore, the least friction resistance from the tyres.
One lap was all I could endure, due to the limited visibility, migraine-inducing driving position, zero ventilation and precious little performance.
