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.

Seeing no need to reinvent the wheel, Nathan had Dermody Diesel Performance keep things simple yet economical and effective when reinforcing the bottom end of his 2006 LBZ. Under all the Illusion Cherry powdercoated intercooler and intake plumbing, there’s a competition-prepped short-block packing an externally balanced crank, ARP main studs, Wagler forged-steel I-beam connecting rods, and cast-aluminum stock compression Mahle pistons. To ensure sufficient oil pressure is always on tap under load, a shimmed oil pump from Wagler sits in place of the factory unit, while Cen-Pe-Co Super High Performance engine oil circulates throughout the engine.
Fastened to the block by way of ARP 2000 head studs sit a set of Wagler-ported factory cylinder heads. In addition to being opened up on the 5-axis CNC, they were treated to Wagler’s 130-lb dual valve spring kit and 4130 chromoly pushrods. Wagler’s one-piece cast street intake is also visible here. For a little dress-up, a set of billet-aluminum upper valve covers from SoCal Diesel were bolted on, along with a pair of billet fuel rails from Wagler.
Facilitating the use of both a T4 turbocharger and the one-piece intake manifold is a twisted pedestal from Wagler. Attached to the pedestal, you’ll find a BorgWarner S366 SX-E. With both its 66 mm forged milled compressor wheel and 73 mm turbine massaged to move more air, the reworked SX-E charger builds roughly 50 psi of boost while only making 60 psi of drive pressure.

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.”

Dermody-Prepped Duramax

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 an injection system composed of 100-percent over injectors and a 12 mm CP3 from S&S Diesel Motorsport, a 165-gph AirDog II-4G system was chosen to handle low-pressure fuel delivery. To feed the 46-percent larger CP3 as much fuel as possible, Nathan keeps supply pressure set between 12-to-14 psi instead of the 8-10 psi you typically see in Duramax applications.
Fuel makes its way toward the AirDog system via this sump from RCD Performance. Installed at the lowest point in the factory tank, it features a ½-inch supply port, a ½-inch return port, and a stand tube on the return side to keep the diesel feeding the lift pump separate from the aerated fuel returning to the tank.

Building Boost

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.

Built to (hopefully) never break, Dermody Diesel put together a killer Allison to back up the potent engine. A host of billet-steel hard-parts includes the input, intermediate, and output shafts, along with a 6-pinion P2 planetary and C2 hub. SunCoast clutches, steels, and some proprietary valve body mods top things off. A high stall, Q model triple-disc converter, complete with a billet stator from Goerend Transmission, affords Nathan the ability to leave the line with plenty of boost on tap.
An Alli-Locker from Fleece Performance Engineering puts precise control over torque converter lockup in Nathan’s right hand. Shortly after leaving the line, and when rpm begins to climb, Nathan locks the converter clutch and doesn’t unlock it again until the end of the track.

All-Billet Allison

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.

Nathan’s first hook of 2019 was the culmination of a long winter’s work. It was clear that he and the folks at Dermody Diesel had done their homework in the offseason. Nathan blazed down the track with a ground speed that was fast-approaching 30 mph and ended up going 312 feet—good enough for Second Place in a strong field of proven Work Stock rigs. If all goes well in 2019, Nathan will consider bumping up to the 2.6 smoothbore Pro Street Diesel Truck class for 2020.
No electronically controlled diesel wins without a good tuner behind it, and Nathan entrusts the EFI Live experts at CTT Tuning for all of his calibrating. Using a DSP5 switch mounted next to the steering column, Nathan can choose between two custom truck pull tunes (let’s just call them “Lots of fuel” and “More fuel”).
Data logging duties are split between a V2 FlashScan and an Insight CTS2, but Nathan always uses the Edge monitor to view key parameters in real time. Vitals of utmost importance are demanded fuel rail pressure vs. actual, boost pressure, lift pump supply pressure, and EGT.
Upgraded to survive the worst of the worst in truck pulling, the rear AAM 1150 has been graced with gun-drilled, 38-spline axles from DHD, a spool, and an ultimate differential support cover from LPW Racing Products. On the other side the differential, you’ll find a one-piece steel driveshaft from ACME-Decatur in place of the factory two-piece unit, along with one of DHD’s billet rear yokes.
Once upon a time, Nathan managed to bend a set of One Up Offroad’s long-gusset adaptable traction bars. After being told he was one of only two truck owners to ever do that, the company sent him a replacement set with chromoly tubing. So far, these bars have had zero problems keeping the beefed up AAM 1150 in place and the rear duals digging.
As you can see, Nathan is still running the factory AAM 9.25 IFS—though it’s been upgraded considerably. Reinforcements and traction enhancements include Cognito Motorsports’ extreme tie rods and straight center link, TufShafts from Fleece Performance Engineering, a welded differential (a.k.a. Miller locker), and RCV Performance’s Ultimate IFS CV axles. But don’t let the CV shaft angle shown here fool you. When the truck is on the hook the front suspension unloads, and both CVs operate in a perfectly straight line.
Looking at the truck’s IFS from the rear, you can see that the factory bump stops are gone and 2-inch blocks are positioned between the Rough Country rear cross member and the control arm. With these blocks in place there is no downward travel. Only upward movement is possible during the course of a pull, but only enough travel to optimize the CV angles without sacrificing the truck’s hitch height out back.

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

You May Also Like


There’s an old saying that goes something like this: The only difference between men and boys is the price of their toys. You’ve probably heard it a hundred times, possibly in the mutterings…

Fastest Passes of 2020

Just when you thought all had been lost in 2020, you get a feel-good article like this in your hands. There’s no denying that Covid-19 shortened most racing schedules, canceled every major…

Diesel Engines in the United States Military

Diesel engines have a wide variety of applications, one of the notable ones being the military. Because of the durability, efficiency, and performance offered by diesel powerplants, it would…