Cruising comfortably on E85

More and more automobile companies are offering E85-compatible vehicles, and American Chevrolet is the latest brand to hit the road with this fuel.

The Cruze minor change is available with three engine choices – a 1.6-litre gasoline, 2.0-litre diesel turbo and a 1.8-litre flex-fuel engine that is capable of running on pure gasoline and gasohol of up to E85 (85 per cent ethanol and 15 per cent gasoline).

Unfortunately, many still do not know what E85 is all about and what its real benefits are. Ethanol, which is usually produced through fermentation of crops such as sugarcane and tapioca, has higher oxygen content (about 30 per cent) compared to pure gasoline. As a result, it burns cleaner. 

In general, the use of the E85 blend will help reduce carbon dioxide (CO2) emissions by as much as 21 per cent. Other emissions such as carbon monoxide, nitrous oxide and sulfur dioxide are also significantly reduced. These gasses contribute to what is known as the “greenhouse effect”, which causes global warming. 

However, there are some disadvantages – primarily increased fuel consumption compared to gasoline. E85 has a lower heat value than gasoline, which means more ethanol is needed to produce the same amount of energy produced by pure gasoline. But it does have a higher octane rating. Still, this does not result in increased engine output as many believe, since the performance increase makes up for the lower energy produced by ethanol.

And despite E85 being lighter on the pocket, you don’t save much when running on the fuel.What you are contributing, however, is helping the country lower its oil imports, since ethanol can be produced locally.

But back to the Cruze, which I must say is a very nice car indeed. I drove the 2.0 turbo diesel several years ago and was highly impressed with its performance and fuel economy. Unfortunately, the price tag is rather high at Bt1.24 million, and many potential Cruze diesel owners may have to opt instead for the 1.8 LTZ, which is more reasonably priced at Bt998,000 (thanks to the lower E85 excise duty).

The 1.8-litre twin-cam 16-valve motor produces 141 horsepower and 177Nm of torque, which is enough to give the Cruze an acceptable performance, although it is no match for the diesel, which offers 20-plus more horsepower and plenty of torque (360Nm).

Power goes through a new six-speed automatic transmission that offers pretty good performance. The “Gen II” gearbox, with manual shift mode, offers smoother shifts and better throttle response, especially in higher gears. While the first-generation gearbox has received some customer complaints, this is a second-generation box that has been improved, according to Chevrolet.

The front strut and rear torsion beam suspension offers a solid ride, and this is another plus that driving enthusiasts will appreciate. Brakes come with ABS and EBD, while ESP (Electronic Stability Programme) is also offered.

Apart from exterior improvements at the front and rear – that is a little difficult to notice compared to the previous model – the Cruze gets several interior upgrades, including a smart-entry function with a start/stop button.

There’s also the new “brownstone” upholstery that looks and feels great, while the trim on the centre console has been upgraded to give the interior a more luxurious feel. The three-spoke steering wheel comes with control buttons for the audio system and cruise control. The audio system supports most auxiliary, USB and Bluetooth devices. Also offered are automatic windshield wipers and headlights.

Although the Cruze might not stand out in the crowd, especially when compared to flashy cars like the Ford Focus or Honda Civic, it is a decent compact car that offers a good level of driving enjoyment.

The E85-compatibility is good, giving you a wide choice of fuels that can be used, and Chevrolet says that it will offer more E85 models in future (presently only the Captiva and Cruze come with E85 variants).

 

E85 and Flex-Fuel Vehicles 

To understand the technology in a Flex-Fuel Vehicle (FFV), we must first consider a few facts about ethanol. Ethanol is corrosive. It also has lower heat value (about 28 per cent lower), which means more ethanol must be used to produce the same amount of energy produced by pure gasoline. Compared to gasoline, ethanol also has a higher octane rating. 

For satisfactory operation using E85, a vehicle must have a fuel system that is E85-compatible to counter the corrosive nature of ethanol. This includes the fuel pump, fuel line and injectors. The engine must also be hardened, while components requiring attention include the pistons, piston rings, valves and valve seals. Since more ethanol needs to be used to produce comparable levels of energy got from gasoline, the fuel pump, fuel line and injectors must also have higher flow rates. 

Because ethanol has a higher octane rating, the ignition timing can be advanced, and this is done by the ECU (Electronic Control Unit), which will advance or retard the ignition timing based on the amount of ethanol in the fuel. Advancing ignition timing improves engine performance, but in an E85 engine, this performance increase makes up for the lower energy produced by ethanol. It does not result in an overall increase in engine output, contrary to popular misconception. The ECU of an FFV adjusts the real-time fuel-flow rate and ignition timing. The flexible nature of the whole application enables the vehicle to run on anything from E0 to E85, hence the term ‘flex-fuel vehicle’ or FFV. 

A common misconception about ethanol is that its use will increase engine performance due to its high-octane nature. Higher octane fuel does allow for advanced ignition timing but performance from this parameter alone is marginal. To achieve overall performance and engine output gains, other parameters need to be considered, including compression ratio (which is factory preset and cannot be changed without extensive modifications), air/fuel mixture, volume and flow rates, state of tune of the engine and ECU calibration. 

 

Chevrolet Cruze 1.8 LTZ A/T specs

Engine: 4-cylinder DOHC 16-valve

Displacement: 1,796cc

Bore and stroke: 80.5x88.2

Compression ratio: 10.5:1

Max power: 141hp/6,200rpm

Max torque: 177Nm/3,800rpm

Transmission: 6-speed automatic

Ratios: 4.449/2.908/1.893/1.446/1.000/0.742

Suspension (f/r): McPherson strut, coil spring, stabilizer/torsion beam,

Steering: Electrically powered rack-and-pinion

Turning circle: 10.6 metres

Brakes (f/r): vented disc/disc with ABS, EBD

 

Dimensions (mm)

Length: 4,600

Width: 1,790

Height: 1,475

Wheelbase: 2,685

Track (f/r): 1,545/1,560

Weight (kgs): 1,315

Wheels: 17-inch alloys

Tyres: 215/50 R17

Fuel tank capacity: 60 litres

Price: Bt998,000

Distributor: Chevrolet Sales (Thailand)