A Cummins-powered dragster blasted into the record books by running a quarter of a mile in just 7.98 seconds from a standing start – representing the world’s fastest time ever run by a diesel vehicle over this distance.

The lightning-fast run, by the Bentz Racing Team, took place on Nov. 14 at the famous Pomona Raceway in California during the National Hot Rod Association World Finals. Powering the dragster, sponsored by Lucas Oil and Cummins Rocky Mountain, is a Dodge Ram Turbo Diesel engine modified to pump out a huge 950 horsepower (hp), running on pure biodiesel.

The muscular diesel that slingshot the dragster into history amazed the crowd. Team owner Scott Bentz picks up the story. With son Dustin at the wheel, “The car was set up pretty aggressive as it was our final run of the season and we knew the car had the potential to run in the low eight-second range. From only a mild burnout using about 70 percent of usual launch boost, the dragster roared down the raceway in a perfectly controlled straight line.”

“We all went nuts when the scoreboard lit up with a 7.98 exit time,” said Bentz. “It’s an experience the team will never forget in front of the huge crowd of hot rod fans gathered at Pomona.”

When not racing diesels, Scott Bentz works as VP On-Highway Engine Business at Cummins Rocky Mountain located in Denver, Colorado. The record-breaking success was due to his vision and the hard work of family and friends. “I believed there was no reason why a diesel engine couldn’t operate head-to-head with the same-size gasoline in the Super Comp class of NHRA (National Hot Rod Association) competition,” said Bentz.

“So back in 1999 we embarked on a project to build a diesel dragster which could eventually break the eight-second barrier. It took until June this year to be the first into the eights with an 8.75-second run – but then a competitor reset that to 8.72. But I never expected to get into the sevens so soon after.”

More About The Diesel Dragster.
The car looks every inch a racer in all black, carrying a bright-red Lucas Oil sponsor’s logo and Cummins Rocky Mountain decal. Although similar in appearance to many other dragsters, the car is uniquely adapted to incorporate the diesel engine. When designing the race car for Scott and the team, there was, of course, only one diesel engine choice and they found that in a used Dodge Ram pickup with 35,000 miles (56,327 km) on the clock.

With some engineering magic, they transformed the modestly powered 210-hp engine into a 950-hp, bred for a racing winner. Key to the modification was fitting two-stage turbocharging in the shape of Holset HX35/40 and HX55/60 hybrids. This delivered the 80 psi needed for extreme intake air boost to burn the large amounts of injected fuel.

A Bosch P7100 mechanically controlled fuel pump was adapted to provide the short – but intense – burst of acceleration required for drag racing. With no intercooler, water injection was added to cool down the intake system. Nitrous oxide was also added for smoke control, to burn down the large amount of injected fuel. A hand-built front cover and some other changes were needed to install the engine within the chassis envelope. A Gear Vendor overdrive and special rear gear ratio were required to match the higher torque output and lower rpm of the engine compared to a gasoline equivalent.

Although dragster engines rarely survive for long due to the massive stress imposed by racing, the 5.9-liter Cummins engine has never even broken a major part – a fitting testament to the inherent strength of the design. The use of 100 percent biodiesel, a renewable energy source, gives the team environmental credentials in the world of drag racing and also offers a higher cetane rating. With increasing public and media attention in the possibility of diesel-powered alternatives to gasoline vehicles in North America, the Bentz Racing Team and other diesel racers are flying the flag for the industry by demonstrating just how much performance potential can be realized from diesel engines.