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Diesel Option for Minimobile!

Diesel-powered Mini Cooper just cool enough for Europe.

The cache and hipster status of the Mini Cooper is undeniable. It’s an automotive cult classic reborn with continual proliferation from the showrooms to the streets. Continued exposure in feature films has also helped make these zippy go-kartesque cars increasingly popular.

To continue in the growth of this niche-vehicle- makes-good is a diesel offering from Mini, which is owned by the BMW Group. The Mini One D was shown at the Frankfurt Auto Show and production of the vehicles began earlier this year. The bulk of the sales are expected to come from the usual consumers of passenger car diesels, namely, Western Europe. As it stands now, the Mini One D will be sold in Germany, France, Italy, Great Britain and Spain. No plans were announced for sales in the United States.

The look and layout of the vehicle is largely unchanged. Some of the subtle alterations include a tailpipe covered by the rear air dam as well as enlarged air intakes to provide more air for the intercooler.

The power plant is, of course, the big change. The engine featured in the Mini One D was developed in a cooperative effort covering two years with Toyota. The basic engine is made in Toyota’s Japanese engine plant in Kamigo. All Mini-specific pieces and components are added prior to installation at the Mini plant in Oxford.

The Mini One D features a four-cylinder diesel with an output of 75 bhp with a maximum torque of 133 lb.ft. The engine is 1.363L with a bore of 73 mm and stroke of 81.5 mm. Compression ratio is 18.5:1. Weight concerns mandated that the cylinder heads and crankcase are both made of cast aluminum. The overall weight of the diesel versus the normal gasoline engine is only 77 lb. heavier.

The pistons operate in gray cast iron cylinders designed to be wear-proof. Each cylinder features two valves, operated by followers running on an overhead camshaft controlling the charge cycle. The camshaft is driven by the crankshaft by a timing chain.

Two poly V-belts, independent of one another, drive the servo pump on the hydraulic power steering and then the alternator, water pump and air conditioning compressor. The front end of the crankshaft features a damper designed to absorb idiosyncratic vibrations and minimize the transmission of vibration to the belt drive. The twomass flywheel also takes part in damping engine vibrations occurring above all at low engine speeds typical of a diesel. While technologies like this are available in higher powered engines in larger vehicles, they are not normally seen in vehicles of this size.

The diesel uses second-generation common rail diesel injection and incorporates computercontrolled fuel injection and high pressure directly into the combustion chamber. The com- mon rail also serves as a pressure reservoir while providing fuel to the injection jets. A pump has been engineered to maintain high pressure in excess of 23,000 psi. This pressure level is meant to atomize the fuel into fine particles to ensure clean combustion.

An electronic engine management system facilitates both the timing and duration of both the pilot and main injection process. Pilot injection feeds a small amount of fuel into the combustion chambers prior to the main injection process with its larger volume of fuel, keeping the proper fuel/air mixture which allows the engine to burn more smoothly. A smoother rise in the pressure of the combustion chamber also results in a reduction of combustion noise over that of a typical diesel. The biggest gain in this method, however, is the fuel economy.

The Mini One D, according to the company, is capable of running distances of over 600 mi. on one tank, which holds 13.2 gal. Reported fuel consumption is somewhere in the neighborhood of 48.7 mpg in the city and 65.7 on the highway. These numbers make this Mini the most beneficial mpg-wise of all the Mini variants produced by the BMW group.

All in all, this vehicle can’t miss. It’s targeted at the people who want it and the winning personality of the car is not compromised by the new power source. In fact, for the markets it’s going to be sold in initially, it has THE power plant choice.