An 800HP LBZ Duramax Built To Do One Thing—And One Thing Only
If you’re raised on a farm, you’ll likely grow up to be a farmer. It’s just what you do. And if you farm in America’s Heartland, chances are pretty good you’ll take an interest in truck and tractor pulling. Things were no different for west-central Illinois native Nathan Beard. In his neck of the woods, the 8,500-pound Work Stock diesel truck class is all the rage. It consists of former work trucks, farm trucks, and daily drivers that have been transformed into highly modified versions of their former selves. Because of class rules, they’re over-fueled and under-turbo’d, yet many of the trucks in this field have no problem making 800 hp or better.
Work Truck to Work Stock
While watching the local Work Stock class take off in popularity was fun to watch, Nathan wanted to get in on the action himself, and by 2018 he was finally ready. To do it, he would simply “repurpose” the 150,000-mile ’06 Chevrolet Silverado 3500 HD he had purchased for farm use. After a season of getting his feet wet in the sport, a host of changes were made over the winter. Then he came out swinging in 2019 with a strong, Second Place finish at the truck’s first hook. The 312-foot ride he and his Chevy made (at nearly 30 mph) definitely got our attention, so we moved in for a closer look…
“Nathan’s bad-in-black Chevy can carry 4,100 rpm down track.”
Knowing the factory LBZ Duramax would never survive the type of abuse it was destined to see, Nathan dropped the engine off at Dermody Diesel Performance in Murrayville, Illinois. Now, an externally-balanced crankshaft (anchored in place with ARP main studs), forged-steel rods from Wagler Competition Products, and LB7-style Mahle cast-aluminum pistons are ready to absorb the kind of cylinder pressure it takes to win. For good measure, one of Wagler’s pinned oil pumps also made the cut. Up top, a pair of Wagler-ported factory heads—equipped with dual valve springs—usher more air in-cylinder.
With fixed geometry turbos ruling the roost in today’s turbo-limited truck pulling classes, Nathan knew from the get-go that a VGT-based charger was out. Meeting local Work Stock rules, he sourced an S366 SX-E from Dermody Diesel that’d been treated to a few tweaks in order to improve airflow. The charger mounts to a T4 twisted pedestal from Wagler, which also facilitates the use of Wagler’s one-piece street intake in place of the original Y-bridge. Hot and cold-side intercooler pipes from HSP Diesel route boost through a Mishimoto intercooler, while PPE exhaust manifolds and up-pipes help drive the turbocharger.
S&S Fuel, CTT Tuning
A set of 100-percent over injectors and a 12 mm CP3 from S&S Diesel Motorsport mean there is no shortage of fuel on tap for the hungry Duramax. The OEM location stroker pump gets its low-pressure fuel supply from a 165-gph AirDog II-4G system mounted along the frame rail, and the lift pump pulls fuel from an RCD Performance sump installed in the factory tank. EFI Live wizardry from the folks at CTT Tuning brings a steady 26,000 psi of rail, just under 50 psi of boost, and at least 800 hp into the equation.
Making the six-speed Allison 1000 structurally sound entailed all billet shafts, a billet P2 planetary and C2 hub, SunCoast-sourced clutches and steels, and a Q model torque converter from Goerend Transmission. The billet stator, triple-disc unit’s high stall speed means Nathan can leave the line with a torrent of boost built up. And thanks to having plenty of horsepower on tap, Nathan’s bad-in-black Chevy can carry 4,100 rpm down track, even in Fourth gear and 4-Lo. An Alli-Locker from Fleece Performance Engineering allows him to lock the converter as soon as rpm allows, and then unlock it near the end of the track.
Rock-Solid, From Top to Bottom
Beyond the horsepower-making recipe, the truck’s suspension and axles have been optimized for surviving their battles with the sled. Front-end downward suspension travel is essentially non-existent, Cognito Motorsports’ extreme tie rods and center link eliminate toe-in, the AAM 9.25 has been treated to Tufshafts and a locker, and the AAM 1150 out back features DHD gun-drilled axleshafts, a full spool, and an LPW Ultimate differential cover. All of the above makes it possible for Nathan to drive his LBZ like he stole it, without fear of breaking it—and the end result is impressive. Of all the Work Stock trucks we’ve seen over the years, Nathan’s may be the fastest. Trust us, if you see his black dually being hauled into your county fair, there’s a good chance it’ll be taking home first-place money.
2006 Chevrolet Silverado 3500 HD
Owner: Nathan Beard
Hometown: Arenzville, Illinois
Odometer: 150,000 miles
Engine: LBZ Duramax
Short Block: Externally balanced factory crankshaft with ARP main studs, Wagler Competition Products forged-steel I-beam rods, standard bore Mahle cast-aluminum stock compression pistons, factory camshaft, Wagler pinned oil pump, PPE oil pan, Fluidampr, Sun Coast billet flex plate
Heads/Valvetrain: Wagler-ported factory cast-aluminum heads with dual valve springs, 4130 chromoly pushrods, ARP 2000 head studs, SoCal Diesel billet-aluminum upper valve covers
Fuel: S&S Diesel Motorsport 100-percent over injectors and 12mm stroker CP3, 165-gph AirDog II-4G system, RCD Performance tank sump
Air: Wagler twisted T4 turbo pedestal with modified BorgWarner S366 SX-E, HSP Diesel intercooler and intake piping with velocity stack, Wagler cast-aluminum street intake, Mishimoto intercooler
Exhaust: PPE manifolds and up-pipes, 3-inch downpipe, 4-inch to 5-inch system, 8-inch bed stack
Electronics: EFI Live ECM and TCM calibrating from CTT Tuning via DSP5 switch, Edge Insight CTS2
Transmission: Dermody Diesel Performance-built Allison 1000 with billet input, intermediate, and output shafts, Sun Coast clutch packs and steels, billet P2 planetary, billet C2 clutch hub, custom valve body with TransGo Jr. shift kit, Goerend Transmission high-stall billet stator triple-disc converter, PPE transmission cooler, Fleece Performance Engineering Alli-Locker
Horsepower: 800 hp (est. at the wheels)
Torque: 1,600 lb-ft (est. at the wheels)
Tires: 315/70R17 General Grabber A/T X (front and rear)
Wheels: 17×9-inch Mayhem Monstir (front), 17×6.5-inch Mayhem Monstir (rear) with 2-inch rear spacers
Axles: RCV Performance Ultimate IFS CV axles, Fleece Performance Engineering TufShafts, welded front differential, rear AAM 1150 with DHD gun-drilled 38-spline axles, spool, and LPW Ultimate differential cover, ACME-Decatur one-piece steel rear drive shaft, DHD billet yoke
Suspension: Rough Country 6-inch lift, Suspension Maxx adjustable torsion bar keys, One Up Offroad chromoly tubing long gusset traction bars, Fox shocks (front and rear), DHD rear suspension stops
Steering: Cognito Motorsports extreme duty tie rods and straight center link