greenspeed s-10, Fuel Curve

Greenspeed S-10 Salt Flat Truck Sets Diesel Record

When Dave Schenker started studying mechanical engineering at Boise State University, he didn’t know that his studies would include runs across the Bonneville Salt Flats setting records in a modified 1998 Chevy S-10 truck. Schenker was an accomplished carpenter before opting to return to college. He helped form Greenspeed, a student club in 2011 to apply his schooling to practical applications. That club evolved into Greenspeed Research a non-profit organization that creates learning opportunities for the STEM disciplines and renewable energy sources.

In 2011 the club took their truck to El Mirage to attack the speed record for diesel trucks. Their twist was using bio-diesel and vegetable oil as their power sources. The truck’s suspension had been re-designed to keep the front end steering straight, with little play in the wheel.

greenspeed s-10, Fuel Curve Greenspeed Research, Bonneville, Diesel Record, Fuel Curve

In their first year they were able to reach a speed of 155 mph and set an unofficial record for a vegetable oil-fueled truck. It was unofficial as no sanctioning bodies recognized a category for vegetable oil. After the 2011 racing season, the Southern California Timing Association (SCTA) updated their rules to allow 100% vegetable oil by itself or as a blend with diesel fuel. The Greenspeed S-10 continued going to various land speed events even snagging an invite to SEMA in 2014. In 2016 they reached 209 mph while racing on vegetable oil back at Bonneville. The truck has hit 1250 horsepower at the rear wheel on the dyno. In theory, they needed at least 850 horses to reach 225 mph.

greenspeed s-10, Fuel Curve

Over the years, Schenker and the team has managed nearly 25 starts on land speed courses and completed ten full runs in the Greenspeed S-10. Schenker noted that while racing there are few points of reference for speed, except for the mile marker cones making for a surreal driving experience. So off they went to SCTA Speed Week in August this year and brought two newly-built engines to compete. Over 550 racers showed up for the week to race the three standard courses; short, long and rookie.

greenspeed s-10, Fuel CurveGreenspeed Research, Bonneville, Diesel Record, Fuel CurveThey first tried running a vegetable oil-fueled engine but were having issues so they opted to swap in their diesel fuel engine for a chance to break an existing ten year speed record of 215.091mph in the C/DT class. Here’s a link to a time lapse video of their engine swap. On their first run they cracked the 200 mph barrier, managing 202mph. A review found some mislabeled switches so they were optimistic for the second round but came in at a disappointing 180 mph. Their calculations indicated that they should have been able to hit 225 mph at 3,500 rpm. They were too late for round three of the races but were in line for the next day’s trials.

greenspeed s-10, Fuel Curve

The fourth round started well, reaching 140 mph until the right rear tire blew. Luckily Schenker was able to stab the parachute and slow down the Greenspeed S-10 using his Bear Brakes to avoid any damage to the truck. Regrettably, the team had no spare and it was Thursday afternoon, with Speed Week shutting down at noon the next day.

Greenspeed Research, Bonneville, Diesel Record, Fuel Curve

Now salt racers are a rare breed and like drag racers, share a common bond attacking the salt. They often share advice, parts, and information in their common goal of setting new land speed records. Another team gladly loaned them a tire so they could still try and race on Friday. Many racers left early and missed seeing Schenker run 223 mph Friday morning. But for a qualifying record, the truck had to pass a new tech impound inspection and make a backup run. The truck cruised through impound and made one last pass on the five-mile course. A record consists of the average of the fastest one-mile segments on the five-mile course in two consecutive runs. They came in at 219.411 mph to break the existing diesel fuel record!

greenspeed s-10, Fuel CurveSchenker completed his schooling and now works for a product design firm, so the land speed racing is a hobby and he is always scrambling for sponsors. He hopes to bring back his vegetable oil engine for another assault on the record books soon. But for now he is happy holding the current diesel fuel record.

greenspeed s-10, Fuel CurvePhotos courtesy of Mike Shipman-Blue Planet Photography and Greenspeed Research

Mark C. Bach is a well preserved automotive junkie, due to the Arizona dry heat. He loves anything that moves and is especially fond of muscle cars and classics.