Daihatsu e:S Concept – previewed in 2009

Daihatsu has revealed that it will be launching an affordable and fuel efficient car as near as September 2011, which is just a few months away. The new car will be Daihatsu’s most fuel efficient car as well as its most affordable car, helping save you money in terms of both purchase cost and running cost. The entry price to purchase will be as low as 800,000 yen (RM30,400) and the car is claimed to have a fuel economy of 30 km per litre – which is one of the highest fuel economy claims for a non-hybrid vehicle so far.

Daihatsu’s 30 km/l mileage claim (on the JC08 mode) is achieved through a set of technologies and processes that Daihatsu collectively calls “e:S Technology”, or Energy Saving Technology. We first heard the term e:S when Daihatsu displayed a very small concept car called the e:S Concept (shown above) at a past Tokyo motorshow.

e:S mainly tackles three areas to produce an increased fuel economy – the powertrain, the vehicle construction, and energy management. Basically, you optimize the source of the power, what the source needs to move, as well as how efficiently the vehicle uses the power produced.

In terms of powertrain improvements, Daihatsu has upped the engine’s compression ratio to 11.3:1 from 10.8:1. They’ve also used new improved injectors that can spray smaller particles for better combustion. There’s also a new “i-EGR” system which uses EGR to reduce pumping losses. There are a host of 11 other improvements which improve general efficiency such as a reduction in chain tension by cutting the chain width, a tension reduction in the piston rings and modification of the oil seal. And finally, there’s an electronic throttle body made of a lightweight resin.

The engine is mated with a CVT transmission that has also received design modifications to improve efficiency. There are a total of 8 improvements which include the use of a high efficiency oil pump and lowering the CVT control pressure. The gear ratio has also been optimised to lower engine load. The CVT works hand in hand with the input from the electronic throttle to optimize the gear ratio for the best fuel economy.

In terms of vehicle construction improvement, Daihatsu says they have identified ways to achieve a weight reduction of 60 kg – in comparison to a Daihatsu Mira 2WD with CVT transmission. This comparison leads me to believe this vehicle may in fact be the preview for a future Daihatsu Mira (eventually Perodua Viva hopefully?).


Daihatsu A Concept – previews 30km/l car styling?

Lightening of the chassis alone contributes to 30 kg, or half of the total weight shaved, thanks to revision to the layout of frame components, the redesign of many components to be a straight in form as possible to reduce the need for reinforcements, and a more effective layout of high tensile steel plates.

The other 30 kg in weight savings have been achieved via redesigning the way the interior parts are made, such as reducing the thickness of the instrument panel and door trims. The CVT transmission’s idle reduction unit has also gone on a diet – using thinner walls for the CVT case, an aluminum oil pump cover and an aluminum planetary carrier, and the introduction of an integrated molding for the secondary sensing gear and the piston.

As with any vehicle with eco ambitions, e:S Technology also employs tyres with low rolling resistance. The entire body is also designed to be more aerodynamic via CAE simulation and wind tunnel testing. The layout of the openings in the bumper and air cleaner ducts have been optimised and the air flow pattern has been improved for better thermal management.

The car’s alternator intelligently boosts power generation during vehicle slowdown – the battery has also been modified to more efficiently handle the increased input during drive situations where the alternator decides it’s a good time to use engine braking time to recharge the battery. The alternator works the other way as well – it cuts power generation by decoupling its clutch during normal operation and acceleration, helping free the engine from the alternator’s parasitic drag.

Daihatsu says this new car will be the world’s first vehicle equipped with a CVT transmission that has “pre-stop idle reduction”. What it basically does it to take the automatic start-stop feature that has been making its way into many cars a step further – now the engine is shut off even while coasting to a stop. The engine will shut off when vehicle speed reduces to 7 km/h or less. Naturally for any automatic transmission to work with the engine off, modifications has to be made – so the CVT now uses an oil pump that is not driven by the motor.

The new Daihatsu A Concept set be unveiling this evening might just showcase how this new compact car due for a September 2011 launch will look like. We certainly hope these technologies will eventually trickle down for usage in Perodua cars.