When setting out to build a go-fast drag truck, most people start with the lightest possible platform and work from there to make it even lighter and faster. But Chase Lunsford is not most people. The co-owner of Kingspeed Race & Repair in Bowling Green, Kentucky, had been wrenching on his 5-speed manual transmission 2001 Dodge Ram 3500 dually for years, improving things and making more power, before he decided to get serious with it. Lunsford and his team decided to go Pro Street racing with the truck and knew they had their work cut out for them.
Not long after deciding to move up to the Pro Street class, Kingspeed partner Michael Cordova cut the frame in half while Lunsford was away and the serious Pro Street effort began. Lunsford, his wife Elizabeth, Steven Cole, and Cordova went to work on building the truck into what you see here today: a purpose built Pro Street diesel drag racer that nished second in the ODSS Pro Street Championship battle for both 2015 and 2016 while taking home wins at the Scheid Diesel Extravaganza and the Rocky Top Diesel Shootout.
MICHAEL CORDOVA CUT THE FRAME IN HALF WHILE LUNSFORD WAS AWAY AND THE SERIOUS PRO STREET EFFORT BEGAN.
The Kingspeed crew performed a “back-half” conversion by removing the rear section of the 3500’s frame far under the cab near the transmission crossmember. Chromoly tubing was used to replace the factory structure and provide mounting points for the rear suspension. The heavy full-dually bed was ditched in favor of a set of SRW bedsides that are secured in place with lightweight tubing to maintain a factory look in pro le, but from the rear the entire lattice work of chromoly tubing is easy to see.
For safety and to further stiffen the chassis, Lunsford and his Kingspeed team installed an NHRA-certi ed 8.50-second roll cage in the cab with support bars that come down to the rear portion of the chassis through the tinted Lexan rear window. The interior was stripped bare to make room for the roll cage; then they installed a Corbeau FX1 Pro race seat as well as a set of Simpson 5-point race harnesses. A quick-release steering column and lightweight racing steering wheel keep the truck pointed in the right direction. The build team also used Lexan to replace the windshield to save weight and offer a safer alternative for track use. To cap off the body modi cations, the truck was wrapped in metallic gray vinyl and treated to gold vinyl graphics with the Kingspeed logo and black sponsor logos on the rear of the bedsides.
POWER TO PAVEMENT
Up front, the 4WD truck puts power to the ground with the stock Dana 60 axle assembly and a set of factory coil springs that were cut down for a better ride height, as well as double-adjustable QA1 shocks. In the rear, the build team installed a Moser Engineering M9 fabricated rear axle assembly for a huge weight reduction over the factory dually axle. The M9 is located with a wishbone link up top and a set of Competition Engineering ladder bars on the sides. Ride height and suspension tuning are determined by a pair of Strange Engineering double-adjustable coilover shocks.
The truck rolls on Hoosier 29×13.50x15LT Quick Time Pro drag tires that are wrapped around lightweight 15×10-inch Holeshot racing wheels at all four corners. In addition to the NHRA-mandated parachute mounted to the rear of the chassis, Lunsford relies on upgraded wheel brakes with Wilwood 6-piston calipers and rotors up front and dual 4-piston Moser calipers and rotors on each side in the rear to whoa down the 4,560-pound truck at the big end of the track.
After the chassis modifications were complete, the Kingspeed team needed a potent powerplant to push the truck down the track. Starting with a 2008 Cummins block, they built a 6.7L high-compression, common-rail race engine. The heart of the engine is a Cummins crankshaft that swings Kingspeed connecting rods and 20:1 Diamond pistons that were built to Kingspeed specifications. A Kingspeed roller cam actuates 1mm oversized valves in the Kingspeed Competition cylinder head with the intake shelf milled off and replaced by a Kingspeed billet aluminum machined intake manifold.
The original VP44 fuel system would not keep up with Lunsford’s go-fast plans, so he went with a common-rail option for the truck. It starts with a mechanical low-pressure pump that draws fuel from the rear-mounted aluminum fuel cell and then feeds into a pair of Fleece Performance Engineering PowerFlo 750 CP3 high-pressure fuel pumps. Then the high-pressure fuel is fed into the fuel rail and handed off to a set of Dynomite Diesel Products Super Mental fuel injectors. To enhance the engine further, the truck has two nitrous bottles and three kits of nitrous to boost performance on demand.
Rather than go with a compound turbo setup, Lunsford and the Kingspeed team chose to keep it simple with a single BorgWarner S400 88mm turbo that’s fed hot exhaust from the engine through a Steed Speed Competition T6 exhaust manifold. A pair of large Turbosmart wastegates is employed to keep boost pressure in the desired range. Spent gases from the turbo and wastegates are directed up through hood stacks, while the compressed charge from the turbo is fed into a Mishimoto 6.0L Ford intercooler before returning to the engine through a Cummins intake elbow. Lunsford uses EFILive tuning to control the engine and estimates that it is making around 2,000 hp and 2,500 lb-ft of torque.
To handle all that power, the Kingspeed team built a competitionready Dodge 47RH transmission that is linked to the engine through an SFI-approved ATS flexplate and Diesel Performance Converters billet torque converter with a 3,800rpm stall speed. A B&M transmission cooler mounted behind the cab near the fuel cell helps keep the transmission cool, while a B&M ProRatchet shifter handles gear selection. The combination has run a best quarter-mile pass of 8.61 seconds at 166 mph and a best eighthmile run of 5.41 seconds at 136.8 mph.
Since the time we shot the truck at the end of the 2016 season, Lunsford and his Kingspeed team decided to make changes in the race team and opted to sell the truck to make room for the team’s new build—a Pro Mod tube chassis truck that they plan to campaign through the 2017 season and beyond. We look forward to seeing the new ride and will bring shots of it to you as soon as we can, but don’t forget about this former dually; we expect to see the new owner Seth Higgins tearing up the track with it on a regular basis! DW