If you've ever watched an automotive race, it might surprise you that participants are actually striving for fuel efficiency.
Indeed, the longer a race car can spend on the track making laps on each tank of fuel, the less time it has to spend stopped in the pits. Case in point - the recent annual running of the Rolex 24 at Daytona endurance race.
This race has been conducted for years and the cars drive for 24 hours with nothing but the occasional stop for miscellaneous repairs, refueling, new tires, and driver swap. As expected, the Daytona racetrack is incredibly fast - with some vehicles reaching nearly 200 mph on the banked oval.
Interestingly, this year Mazda brought three diesel-powered race cars to the event for the inaugural running of the GX class. The race was used to help promote the industry heavyweight's new Skyactiv-D diesel engine technology, which will be coming to Mazda showrooms later this year.
The vehicles were a trio of Mazda6 sedans, each powered by what seems like an unlikely engine: in line 4-cylinder turbo diesel engines displacing 2.2-liters. The engines produce 400 hp at 5000 RPM, which was the GX class target, along with very impressive torque at 445 pound-foot at 3600 RPMs.
Most of the actually race car has very little in common with it production counterpart you might see on the roads in your hometown. Indeed, they are constructed using a Speedsource tubular space frame and a host of racecar performance parts. You might be surprised to learn that the 2.2-liter Skyactiv-D engines in the vehicles use 60% stock components, including the engine block and head. Meaning, over 250 parts of the race car engine are stock parts that will be found in the production vehicle.
Unfortunately for Mazda, two of the diesel race cars dropped out of the race with blown engines and the third failed to finish the race. Racing for 24 hours straight at speeds approaching 200 mph is very demanding, indeed. Fortunately, Mazda will be offering gasoline-powered versions of Skyactiv engines in its lineup as well.